100 results on '"Stephen E. Rose"'
Search Results
2. Salivaomics as a Potential Tool for Predicting Alzheimer’s Disease During the Early Stages of Neurodegeneration
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Maryam Hor, Jeff Faunt, Maxime François, John Maddison, Jian-Wei Liu, Avinash V. Karpe, David J. Beale, James D. Doecke, Jane Hecker, Sally Johns, Wayne R. Leifert, and Stephen E. Rose
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0301 basic medicine ,Male ,Proteomics ,Saliva ,Disease ,Bioinformatics ,Pathogenesis ,03 medical and health sciences ,0302 clinical medicine ,Metabolomics ,Alzheimer Disease ,Predictive Value of Tests ,medicine ,Humans ,Cognitive Dysfunction ,Aged ,Aged, 80 and over ,saliva ,business.industry ,General Neuroscience ,Disease progression ,Neurodegeneration ,systems biology ,Neurodegenerative Diseases ,General Medicine ,medicine.disease ,Omics ,metabolomics ,Psychiatry and Mental health ,Clinical Psychology ,030104 developmental biology ,Early Diagnosis ,Female ,multi-omics integration ,Geriatrics and Gerontology ,business ,Alzheimer’s disease ,030217 neurology & neurosurgery ,Biomarkers ,Research Article - Abstract
Background: The metabolomic and proteomic basis of mild cognitive impairment (MCI) and Alzheimer’s disease (AD) is poorly understood and the relationships between systemic abnormalities in metabolism and AD/AMCI pathogenesis are unclear. Objective: The aim of the study was to compare the metabolomic and proteomic signature of saliva from cognitively normal and patients diagnosed with MCI or AD, to identify specific cellular pathways altered with the progression of the disease. Methods: We analyzed 80 saliva samples from individuals with MCI or AD as well as age- and gender-matched healthy controls. Saliva proteomic and metabolomic analyses were conducted utilizing mass spectrometry methods and data combined using pathway analysis. Results: We found significant alterations in multiple cellular pathways, demonstrating that at the omics level, disease progression impacts numerous cellular processes. Multivariate statistics using SIMCA showed that partial least squares-data analysis could be used to provide separation of the three groups. Conclusion: This study found significant changes in metabolites and proteins from multiple cellular pathways in saliva. These changes were associated with AD, demonstrating that this approach might prove useful to identify new biomarkers based upon integration of multi-omics parameters.
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- 2021
3. Chronic white matter changes detected using diffusion tensor imaging following adult traumatic brain injury and their relationship to cognition
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Stephen E. Rose, Kerstin Pannek, Jurgen Fripp, Jane L. Mathias, Lynn Ward, and Erica J. Wallace
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Adult ,Male ,medicine.medical_specialty ,Traumatic brain injury ,Splenium ,Neuropsychological Tests ,Audiology ,Corpus callosum ,050105 experimental psychology ,White matter ,Executive Function ,Cognition ,Memory ,Brain Injuries, Traumatic ,Fractional anisotropy ,medicine ,Humans ,Attention ,Cognitive Dysfunction ,0501 psychology and cognitive sciences ,Longitudinal Studies ,Effects of sleep deprivation on cognitive performance ,Brain Mapping ,05 social sciences ,Fornix ,Brain ,medicine.disease ,White Matter ,nervous system diseases ,Diffusion Tensor Imaging ,Neuropsychology and Physiological Psychology ,medicine.anatomical_structure ,nervous system ,Anisotropy ,Female ,Psychology - Abstract
Objective: White matter (WM) changes detected using diffusion tensor imaging (DTI) are reportedly related to cognitive outcomes following traumatic brain injury (TBI), but much existing research is underpowered or has only examined general outcomes, rather than cognitive functioning. Method: A large sample of adults who had sustained mild, moderate or severe TBIs seven months prior (N = 165) and a control group (N = 106) underwent DTI and cognitive testing. Fractional anisotropy and mean diffusivity were calculated for 5 regions (corpus callosum: genu, body, splenium; fornix; superior longitudinal fasciculus) that recent meta-analyses identified as being affected by TBI and related to cognition following TBI. Memory, attention and executive functioning, which are often affected by TBI, were assessed. Results: Overall, mild TBI did not show significant WM or cognitive changes, relative to controls, but moderate to severe TBI was associated with large WM alterations (all regions) and poorer cognitive performance. No significant correlations were found between DTI findings and cognition in the moderate to severe group. Conclusions: The findings have shown that moderate to severe TBI leads to considerable WM and cognitive changes. Early and ongoing examination of mild TBI is needed to determine whether WM and cognitive changes are initially present and, if so, when they resolve. (PsycInfo Database Record (c) 2020 APA, all rights reserved).
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- 2020
4. Understanding the impact of bilateral brain injury in children with unilateral cerebral palsy
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Alex M. Pagnozzi, Jurgen Fripp, Kerstin Pannek, Roslyn N. Boyd, Simona Fiori, and Stephen E. Rose
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Male ,medicine.medical_treatment ,Precuneus ,Functional Laterality ,Corpus Callosum ,Cohort Studies ,0302 clinical medicine ,Thalamus ,Gray Matter ,Child ,Research Articles ,Cerebral Cortex ,Radiological and Ultrasound Technology ,05 social sciences ,Gross Motor Function Classification System ,Magnetic Resonance Imaging ,White Matter ,medicine.anatomical_structure ,Neurology ,Child, Preschool ,Brain size ,Laterality ,Cardiology ,Female ,Anatomy ,Primary motor cortex ,Research Article ,medicine.medical_specialty ,Adolescent ,Splenium ,Neuroimaging ,050105 experimental psychology ,Cerebral palsy ,03 medical and health sciences ,Internal medicine ,medicine ,Humans ,0501 psychology and cognitive sciences ,Radiology, Nuclear Medicine and imaging ,bilateral ,interventions ,cerebral palsy ,business.industry ,medicine.disease ,Transcranial magnetic stimulation ,Brain Injuries ,plasticity ,Neurology (clinical) ,business ,030217 neurology & neurosurgery - Abstract
The presence of bilateral brain injury in patients with unilateral cerebral palsy (CP) may impact neuroplasticity in the ipsilateral hemisphere; however, this pattern of injury is typically under‐analyzed due to the lack of methods robust to severe injury. In this study, injury‐robust methods have been applied to structural brain magnetic resonance imaging (MRI) data of a cohort of 91 children with unilateral CP (37 with unilateral and 54 with bilateral brain injury, 4–17 years) and 44 typically developing controls (5–17 years), to determine how brain structure is associated with concurrent motor function, and if these associations differ between patients with unilateral or bilateral injury. Regression models were used to associate these measures with two clinical scores of hand function, with patient age, gender, brain injury laterality, and interaction effects included. Significant associations with brain structure and motor function were observed (Pearson's r = .494–.716), implicating several regions of the motor pathway, and demonstrating an accurate prediction of hand function from MRI, regardless of the extent of brain injury. Reduced brain volumes were observed in patients with bilateral injury, including volumes of the thalamus and corpus callosum splenium, compared to those with unilateral injury, and the healthy controls. Increases in cortical thickness in several cortical regions were observed in cohorts with unilateral and bilateral injury compared to controls, potentially suggesting neuroplasticity might be occurring in the inferior frontal gyrus and the precuneus. These findings identify prospective useful target regions for transcranial magnetic stimulation intervention.
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- 2020
5. A fixel‐based analysis of micro‐ and macro‐structural changes to white matter following adult traumatic brain injury
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Jane L. Mathias, Lynn Ward, Kerstin Pannek, Jurgen Fripp, Erica J. Wallace, and Stephen E. Rose
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Male ,Corpus callosum ,Corpus Callosum ,0302 clinical medicine ,Internal Capsule ,Brain Injuries, Traumatic ,adults ,Research Articles ,Aged, 80 and over ,neuroimaging ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,diffusion‐weighted imaging ,traumatic brain injury ,05 social sciences ,Middle Aged ,fixel‐based analysis ,White Matter ,medicine.anatomical_structure ,Neurology ,External Capsule ,Female ,Anatomy ,Research Article ,Adult ,External capsule ,Cerebral Peduncle ,Traumatic brain injury ,050105 experimental psychology ,White matter ,03 medical and health sciences ,Young Adult ,Neuroimaging ,medicine ,Reaction Time ,Humans ,0501 psychology and cognitive sciences ,Radiology, Nuclear Medicine and imaging ,Glasgow Coma Scale ,Brain Concussion ,Aged ,business.industry ,Cerebral peduncle ,Magnetic resonance imaging ,medicine.disease ,Diffusion Magnetic Resonance Imaging ,nervous system ,Neurology (clinical) ,Nuclear medicine ,business ,030217 neurology & neurosurgery ,Diffusion MRI ,Follow-Up Studies - Abstract
Diffusion tensor imaging is often used to assess white matter (WM) changes following traumatic brain injury (TBI), but is limited in voxels that contain multiple fibre tracts. Fixel‐based analysis (FBA) addresses this limitation by using a novel method of analysing high angular resolution diffusion‐weighted imaging (HARDI) data. FBA examines three aspects of each fibre tract within a voxel: tissue micro‐structure (fibre density [FD]), tissue macro‐structure (fibre‐bundle cross section [FC]) and a combined measure of both (FD and fibre‐bundle cross section [FDC]). This study used FBA to identify the location and extent of micro‐ and macro‐structural changes in WM following TBI. A large TBI sample (N mild = 133, N moderate–severe = 29) and control group (healthy and orthopaedic; N = 107) underwent magnetic resonance imaging with HARDI and completed reaction time tasks approximately 7 months after their injury (range: 98–338 days). The TBI group showed micro‐structural differences (lower FD) in the corpus callosum and forceps minor, compared to controls. Subgroup analyses revealed that the mild TBI group did not differ from controls on any fixel metric, but the moderate to severe TBI group had significantly lower FD, FC and FDC in multiple WM tracts, including the corpus callosum, cerebral peduncle, internal and external capsule. The moderate to severe TBI group also had significantly slower reaction times than controls, but the mild TBI group did not. Reaction time was not related to fixel findings. Thus, the WM damage caused by moderate to severe TBI manifested as fewer axons and a reduction in the cross‐sectional area of key WM tracts.
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- 2020
6. Fully automated delineation of the optic radiation for surgical planning using clinically feasible sequences
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Jurgen Fripp, José V. Manjón, Julie Trinder, Stephen E. Rose, Marita Prior, Hamish Alexander, Eloy Martinez-Heras, Rosalind L. Jeffree, Sara Llufriu, Elisabeth Solana, and Lee B. Reid
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Adult ,Male ,medicine.medical_specialty ,Computer science ,Diffusion magnetic resonance imaging ,tractography ,Surgical planning ,DICOM ,Young Adult ,Image Interpretation, Computer-Assisted ,Preoperative Care ,medicine ,temporal lobectomy ,Humans ,Optic radiation ,Radiology, Nuclear Medicine and imaging ,Segmentation ,Visual Pathways ,Quadrantanopia ,Research Articles ,diffusion magnetic resonance imaging ,Epilepsy ,Radiological and Ultrasound Technology ,medicine.disease ,Anterior Temporal Lobectomy ,optic radiation ,Dissection ,medicine.anatomical_structure ,Diffusion Tensor Imaging ,Neurology ,Temporal lobectomy ,FISICA APLICADA ,epilepsy ,Female ,Neurology (clinical) ,Radiology ,Anatomy ,Meyer's Loop ,Tractography ,Diffusion MRI ,Research Article - Abstract
Quadrantanopia caused by inadvertent severing of Meyer's Loop of the optic radiation is a well‐recognised complication of temporal lobectomy for conditions such as epilepsy. Dissection studies indicate that the anterior extent of Meyer's Loop varies considerably between individuals. Quantifying this for individual patients is thus an important step to improve the safety profile of temporal lobectomies. Previous attempts to delineate Meyer's Loop using diffusion MRI tractography have had difficulty estimating its full anterior extent, required manual ROI placement, and/or relied on advanced diffusion sequences that cannot be acquired routinely in most clinics. Here we present CONSULT: a pipeline that can delineate the optic radiation from raw DICOM data in a completely automated way via a combination of robust pre‐processing, segmentation, and alignment stages, plus simple improvements that bolster the efficiency and reliability of standard tractography. We tested CONSULT on 696 scans of predominantly healthy participants (539 unique brains), including both advanced acquisitions and simpler acquisitions that could be acquired in clinically acceptable timeframes. Delineations completed without error in 99.4% of the scans. The distance between Meyer's Loop and the temporal pole closely matched both averages and ranges reported in dissection studies for all tested sequences. Median scan‐rescan error of this distance was 1 mm. When tested on two participants with considerable pathology, delineations were successful and realistic. Through this, we demonstrate not only how to identify Meyer's Loop with clinically feasible sequences, but also that this can be achieved without fundamental changes to tractography algorithms or complex post‐processing methods., Quadrantanopia caused by inadvertent severing of Meyer's Loop of the optic radiation is a well‐recognised complication of temporal lobectomy. We demonstrated a fully automated pipeline that could delineate this structure reliably and realistically on more than 500 unique brains, including both advanced and more clinically‐accessible acquisitions. Results were in line with historical dissections studies and median scan‐rescan error was 1 mm.
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- 2021
7. Early clinical and MRI biomarkers of cognitive and motor outcomes in very preterm born infants
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Jurgen Fripp, Roslyn N. Boyd, Kerstin Pannek, Stephen E. Rose, Mark D. Chatfield, Andrea Guzzetta, Joanne M. George, Paul B. Colditz, Robert S. Ware, and Simona Fiori
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General movements assessment ,Male ,Pediatrics ,medicine.medical_specialty ,Neurological examination ,Grey matter ,Motor Activity ,Bayley Scales of Infant Development ,03 medical and health sciences ,0302 clinical medicine ,Cognition ,030225 pediatrics ,medicine ,Humans ,Prospective Studies ,Toddler ,Prospective cohort study ,medicine.diagnostic_test ,business.industry ,Postmenstrual Age ,Infant, Newborn ,Gestational age ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Infant, Extremely Premature ,Pediatrics, Perinatology and Child Health ,Female ,business ,030217 neurology & neurosurgery - Abstract
This study aimed to identify which MRI and clinical assessments, alone or in combination, from (i) early (32 weeks postmenstrual age, PMA), (ii) term equivalent age (TEA) and (iii) 3 months corrected age (CA) are associated with motor or cognitive outcomes at 2 years CA in infants born31 weeks gestation.Prospective cohort study of 98 infants who underwent early and TEA MRI (n = 59 males; median birth gestational age 28 + 5 weeks). Hammersmith Neonatal Neurological Examination (HNNE), NICU Neonatal Neurobehavioural Scale and General Movements Assessment (GMs) were performed early and at TEA. Premie-Neuro was performed early and GMs, Test of Infant Motor Performance and visual assessment were performed at TEA and 3 months CA. Neurodevelopmental outcomes were determined using Bayley Scales of Infant and Toddler Development 3rd edition.The best combined motor outcome model included 3-month GMs (β = -11.41; 95% CI = -17.34, -5.49), TEA MRI deep grey matter score (β = -6.23; 95% CI = -9.47, -2.99) and early HNNE reflexes (β = 3.51; 95% CI = 0.86, 6.16). Combined cognitive model included 3-month GMs (β = -10.01; 95% CI = -15.90, -4.12) and TEA HNNE score (β = 1.33; 95% CI = 0.57, 2.08).Early neonatal neurological assessment improves associations with motor outcomes when combined with term MRI and 3-month GMs. Term neurological assessment combined with 3-month GMs improves associations with cognitive outcomes.We present associations between 32- and 40-week MRI, comprehensive clinical assessments and later 2-year motor and cognitive outcomes for children born31 weeks gestation. MRI and clinical assessment of motor, neurological and neurobehavioural function earlier than term equivalent age in very preterm infants is safe and becoming more available in clinical settings. Most of these children are discharged from hospital before term age and so completing assessments prior to discharge can assist with follow up. MRI and neurological assessment prior to term equivalent age while the child is still in hospital can provide earlier identification of children at highest risk of adverse outcomes and guide follow-up screening and intervention services.
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- 2020
8. Prediction of childhood brain outcomes in infants born preterm using neonatal MRI and concurrent clinical biomarkers (PREBO-6): study protocol for a prospective cohort study
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Paul B. Colditz, Karen M. Barlow, Jurgen Fripp, Roslyn N. Boyd, Samudragupta Bora, Robert S. Ware, Stephen E. Rose, Rebecca L Jendra, Alex M. Pagnozzi, Kerstin Pannek, Kartik K. Iyer, Joanne M. George, Shaneen J. Leishman, and Jane E Bursle
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Male ,medicine.medical_specialty ,Pediatrics ,paediatric neurology ,Psychological intervention ,lcsh:Medicine ,Gestational Age ,Academic achievement ,Electroencephalography ,neonatology ,Cerebral palsy ,perinatology ,Early Medical Intervention ,Medicine ,magnetic resonance imaging ,Humans ,Cognitive Dysfunction ,Neonatology ,Prospective Studies ,Motor Neuron Disease ,Prospective cohort study ,Language ,Academic Success ,medicine.diagnostic_test ,business.industry ,Cerebral Palsy ,lcsh:R ,Australia ,Infant, Newborn ,Brain ,Cognition ,Paediatrics ,General Medicine ,medicine.disease ,Mental health ,Mental Health ,Neurodevelopmental Disorders ,Quality of Life ,developmental neurology & neurodisability ,Premature Birth ,Female ,paediatric radiology ,business ,Biomarkers ,Follow-Up Studies - Abstract
IntroductionInfants born very preterm are at risk of adverse neurodevelopmental outcomes, including cognitive deficits, motor impairments and cerebral palsy. Earlier identification enables targeted early interventions to be implemented with the aim of improving outcomes.Methods and analysisProtocol for 6-year follow-up of two cohorts of infants born AimsExamine the ability of early neonatal MRI, EEG and concurrent clinical measures at 32 weeks PMA to predict motor, cognitive, language, academic achievement and mental health outcomes at 6 years CA.Determine if early brain abnormalities persist and are evident on brain MRI at 6 years CA and the relationship to EEG and concurrent motor, cognitive, language, academic achievement and mental health outcomes.Ethics and disseminationEthical approval has been obtained from Human Research Ethics Committees at Children’s Health Queensland (HREC/19/QCHQ/49800) and The University of Queensland (2019000426). Study findings will be presented at national and international conferences and published in peer-reviewed journals.Trial registration numberACTRN12619000155190p.Web address of trialhttp://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12619000155190p
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- 2020
9. Relationship between very early brain structure and neuromotor, neurological and neurobehavioral function in infants born <31 weeks gestational age
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Robert S. Ware, Joanne M. George, Jurgen Fripp, Stephen E. Rose, Andrea Guzzetta, Simona Fiori, Roslyn N. Boyd, Paul B. Colditz, Michael David, and Kerstin Pannek
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Male ,General movements assessment ,Pediatrics ,medicine.medical_specialty ,Neurological examination ,Neuromotor ,White matter ,03 medical and health sciences ,Magnetic resonance imaging ,Neurobehaviour ,Neurological ,Preterm ,Pediatrics, Perinatology and Child Health ,Obstetrics and Gynecology ,Child Development ,0302 clinical medicine ,030225 pediatrics ,medicine ,Humans ,Prospective cohort study ,medicine.diagnostic_test ,business.industry ,Infant, Newborn ,Postmenstrual Age ,Brain ,Gestational age ,Perinatology and Child Health ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Motor Skills ,Infant Behavior ,Female ,Abnormality ,business ,Infant, Premature ,030217 neurology & neurosurgery - Abstract
This study aimed to examine associations between structural MRI and concurrent motor, neurological and neurobehavioral measures at 30-32 weeks postmenstrual age (PMA; 'Early'), and at term equivalent age ('Term').In this prospective cohort study, infants underwent Early MRI (n = 119; 73 male; median 32 weeks 1 day PMA) and Term MRI (n = 102; 61 male; median 40 weeks 4 days PMA) at 3 T. Structural images were scored generating white matter (WM), cortical gray matter, deep gray matter, cerebellar and global brain abnormality scores. Clinical measures were General Movements Assessment (GMs), Hammersmith Neonatal Neurological Examination (HNNE) and NICU Neonatal Neurobehavioral Scale (NNNS). The Premie-Neuro was administered Early and the Test of Infant Motor Performance (TIMP) and a visual assessment at Term.Early MRI cerebellar scores were strongly associated with neurological components of HNNE (reflexes), NNNS (Hypertonicity), the Premie-Neuro neurological subscale (regression coefficient β = -0.06; 95% confidence interval CI = -0.09, -0.04; p .001) and cramped-synchronized GMs (β = 1.10; 95%CI = 0.57, 1.63; p .001). Term MRI WM and global scores were strongly associated with the TIMP (WM β = -1.02; 95%CI = -1.67, -0.36; p = .002; global β = -1.59; 95%CI = -2.62, -0.56; p = .001).Brain structure on Early and Term MRI was associated with concurrent motor, neurological and neurobehavioral function in very preterm infants.
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- 2018
10. Fixel-based analysis reveals alterations is brain microstructure and macrostructure of preterm-born infants at term equivalent age
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Paul B. Colditz, Jurgen Fripp, Kerstin Pannek, Simona Fiori, Stephen E. Rose, Joanne M. George, and Roslyn N. Boyd
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Male ,Fixel-based analysis ,Pediatrics ,medicine.medical_specialty ,Cognitive Neuroscience ,Splenium ,Gestational Age ,Anterior commissure ,Corpus callosum ,lcsh:Computer applications to medicine. Medical informatics ,lcsh:RC346-429 ,030218 nuclear medicine & medical imaging ,Diffusion ,03 medical and health sciences ,Neonate ,0302 clinical medicine ,Neuroimaging ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,lcsh:Neurology. Diseases of the nervous system ,Brain Mapping ,business.industry ,Infant, Newborn ,Postmenstrual Age ,Brain ,Gestational age ,Regular Article ,Magnetic Resonance Imaging ,White Matter ,Diffusion Magnetic Resonance Imaging ,Neurology ,lcsh:R858-859.7 ,Female ,Neurology (clinical) ,Nerve Net ,Abnormality ,Prematurity ,business ,Infant, Premature ,030217 neurology & neurosurgery ,Diffusion MRI - Abstract
Preterm birth causes significant disruption in ongoing brain development, frequently resulting in adverse neurodevelopmental outcomes. Brain imaging using diffusion MRI may provide valuable insight into microstructural properties of the developing brain. The aim of this study was to establish whether the recently introduced fixel-based analysis method, with its associated measures of fibre density (FD), fibre bundle cross-section (FC), and fibre density and bundle cross-section (FDC), is suitable for the investigation of the preterm infant brain at term equivalent age. High-angular resolution diffusion weighted images (HARDI) of 55 preterm-born infants and 20 term-born infants, scanned around term-equivalent age, were included in this study (3 T, 64 directions, b = 2000 s/mm2). Postmenstrual age at the time of MRI, and intracranial volume (FC and FDC only), were identified as confounding variables. Gestational age at birth was correlated with all fixel measures in the splenium of the corpus callosum. Compared to term-born infants, preterm infants showed reduced FD, FC, and FDC in a number of regions, including the corpus callosum, anterior commissure, cortico-spinal tract, optic radiations, and cingulum. Preterm infants with minimal macroscopic brain abnormality showed more extensive reductions than preterm infants without any macroscopic brain abnormality; however, little differences were observed between preterm infants with no and with minimal brain abnormality. FC showed significant reductions in preterm versus term infants outside regions identified with FD and FDC, highlighting the complementary role of these measures. Fixel-based analysis identified both microstructural and macrostructural abnormalities in preterm born infants, providing a more complete picture of early brain development than previous diffusion tensor imaging (DTI) based approaches., Highlights • Gestational age at birth associated with measurements in corpus callosum splenium. • Preterms without macroscopic brain abnormality show differences to term infants. • No differences between preterms with minimal versus without abnormality detected.
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- 2018
11. Positron emission tomography and magnetic resonance imaging in experimental human malaria to identify organ-specific changes in morphology and glucose metabolism: A prospective cohort study
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Paul Thomas, Nicholas M. Anstey, Melissa Fernandez, Ashley Gillman, Stephen E. Rose, Jennie Roberts, John Woodford, James S. McCarthy, Bridget E. Barber, Stephen Woolley, and Peter Jenvey
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Male ,0301 basic medicine ,Plasmodium ,Physiology ,Plasmodium vivax ,Hematocrit ,Gastroenterology ,Diagnostic Radiology ,Medical Conditions ,0302 clinical medicine ,Bone Marrow ,Immune Physiology ,Medicine and Health Sciences ,Prospective Studies ,Malaria, Falciparum ,Prospective cohort study ,Tomography ,Protozoans ,medicine.diagnostic_test ,biology ,Radiology and Imaging ,Malarial Parasites ,Eukaryota ,General Medicine ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Liver ,Medicine ,Female ,Queensland ,Research Article ,medicine.drug ,medicine.medical_specialty ,Imaging Techniques ,Immunology ,Plasmodium falciparum ,030231 tropical medicine ,Neuroimaging ,Spleen ,Research and Analysis Methods ,Young Adult ,03 medical and health sciences ,Diagnostic Medicine ,Internal medicine ,Parasite Groups ,parasitic diseases ,Parasitic Diseases ,Malaria, Vivax ,medicine ,Humans ,Fluorodeoxyglucose ,business.industry ,Organisms ,Biology and Life Sciences ,Tropical Diseases ,biology.organism_classification ,Parasitic Protozoans ,Spine ,Malaria ,Glucose ,030104 developmental biology ,Immune System ,Positron-Emission Tomography ,Parasitology ,Bone marrow ,Hemoglobin ,business ,Apicomplexa ,Positron Emission Tomography ,Neuroscience - Abstract
Background Plasmodium vivax has been proposed to infect and replicate in the human spleen and bone marrow. Compared to Plasmodium falciparum, which is known to undergo microvascular tissue sequestration, little is known about the behavior of P. vivax outside of the circulating compartment. This may be due in part to difficulties in studying parasite location and activity in life. Methods and findings To identify organ-specific changes during the early stages of P. vivax infection, we performed 18-F fluorodeoxyglucose (FDG) positron emission tomography/magnetic resonance imaging (PET/MRI) at baseline and just prior to onset of clinical illness in P. vivax experimentally induced blood-stage malaria (IBSM) and compared findings to P. falciparum IBSM. Seven healthy, malaria-naive participants were enrolled from 3 IBSM trials: NCT02867059, ACTRN12616000174482, and ACTRN12619001085167. Imaging took place between 2016 and 2019 at the Herston Imaging Research Facility, Australia. Postinoculation imaging was performed after a median of 9 days in both species (n = 3 P. vivax; n = 4 P. falciparum). All participants were aged between 19 and 23 years, and 6/7 were male. Splenic volume (P. vivax: +28.8% [confidence interval (CI) +10.3% to +57.3%], P. falciparum: +22.9 [CI −15.3% to +61.1%]) and radiotracer uptake (P. vivax: +15.5% [CI −0.7% to +31.7%], P. falciparum: +5.5% [CI +1.4% to +9.6%]) increased following infection with each species, but more so in P. vivax infection (volume: p = 0.72, radiotracer uptake: p = 0.036). There was no change in FDG uptake in the bone marrow (P. vivax: +4.6% [CI −15.9% to +25.0%], P. falciparum: +3.2% [CI −3.2% to +9.6%]) or liver (P. vivax: +6.2% [CI −8.7% to +21.1%], P. falciparum: −1.4% [CI −4.6% to +1.8%]) following infection with either species. In participants with P. vivax, hemoglobin, hematocrit, and platelet count decreased from baseline at the time of postinoculation imaging. Decrements in hemoglobin and hematocrit were significantly greater in participants with P. vivax infection compared to P. falciparum. The main limitations of this study are the small sample size and the inability of this tracer to differentiate between host and parasite metabolic activity. Conclusions PET/MRI indicated greater splenic tropism and metabolic activity in early P. vivax infection compared to P. falciparum, supporting the hypothesis of splenic accumulation of P. vivax very early in infection. The absence of uptake in the bone marrow and liver suggests that, at least in early infection, these tissues do not harbor a large parasite biomass or do not provoke a prominent metabolic response. PET/MRI is a safe and noninvasive method to evaluate infection-associated organ changes in morphology and glucose metabolism., John Woodford and co-authors use positron emission tomography/magnetic resonance imaging (PET/MRI) to describe unique splenic morphology and metabolism in early P. vivax infection., Author summary Why was this study done? In contrast to Plasmodium falciparum, blood-stage Plasmodium vivax is not traditionally thought to accumulate outside of the circulating blood compartment. Emerging data suggest that a hidden compartment of P. vivax may exist outside of circulation, in reticulocyte (very young red blood cells)-containing organs. The presence of a hidden compartment affects our understanding of the basic biology and pathology of this common parasite and may have implications when developing antimalarial treatments. Studying the accumulation of malaria parasites is extremely challenging in vivo and has historically been limited to late stage disease and postmortem studies. What did the researchers do and find? We performed whole body magnetic resonance imaging (MRI) and positron emission tomography (PET) in individuals undergoing experimental malaria infection to identify changes in organ morphology and glucose metabolism following infection. Splenic uptake of radiolabeled glucose increased following P. vivax and P. falciparum infection and was more pronounced in the P. vivax group. Glucose uptake in the liver and bone marrow was not increased following infection with either P. vivax or P. falciparum. What do these findings mean? Increased splenic glucose metabolism is present in the early stages of infection with both P. vivax and P. falciparum and is more pronounced in P. vivax, consistent with other emerging evidence of a greater predilection for the spleen in P. vivax than P. falciparum. Functional medical imaging may be a useful tool to study biological processes in experimental malaria infection.
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- 2021
12. Brain changes following four weeks of unimanual motor training: Evidence from fMRI‐guided diffusion MRI tractography
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Ross Cunnington, Stephen E. Rose, Lee B. Reid, Martin V. Sale, and Jason B. Mattingley
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Adult ,Male ,Adolescent ,Pyramidal Tracts ,Functional Laterality ,050105 experimental psychology ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Fractional anisotropy ,Basal ganglia ,medicine ,Humans ,Learning ,0501 psychology and cognitive sciences ,Radiology, Nuclear Medicine and imaging ,Research Articles ,Brain Mapping ,Neuronal Plasticity ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,05 social sciences ,Brain ,Anatomy ,Magnetic Resonance Imaging ,White Matter ,Dorsolateral prefrontal cortex ,medicine.anatomical_structure ,Neurology ,Motor Skills ,Corticospinal tract ,Female ,Neurology (clinical) ,Functional magnetic resonance imaging ,Psychology ,030217 neurology & neurosurgery ,Diffusion MRI ,Motor cortex ,Tractography - Abstract
We have reported reliable changes in behavior, brain structure, and function in 24 healthy right‐handed adults who practiced a finger‐thumb opposition sequence task with their left hand for 10 min daily, over 4 weeks. Here, we extend these findings by using diffusion MRI to investigate white‐matter changes in the corticospinal tract, basal‐ganglia, and connections of the dorsolateral prefrontal cortex. Twenty‐three participant datasets were available with pre‐training and post‐training scans. Task performance improved in all participants (mean: 52.8%, SD: 20.0%; group P
- Published
- 2017
13. Brain microstructure and morphology of very preterm-born infants at term equivalent age: Associations with motor and cognitive outcomes at 1 and 2 years
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Kerstin Pannek, Joanne M. George, Jurgen Fripp, Stephen E. Rose, Paul B. Colditz, and Roslyn N. Boyd
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Male ,Term-equivalent age ,Pediatrics ,medicine.medical_specialty ,Cognitive Neuroscience ,Neurodevelopment ,Pyramidal Tracts ,050105 experimental psychology ,Diffusion MRI ,lcsh:RC321-571 ,Corpus Callosum ,03 medical and health sciences ,0302 clinical medicine ,Corrected Age ,Child Development ,Cognition ,Early prediction ,Cognitive development ,medicine ,Humans ,0501 psychology and cognitive sciences ,Brain magnetic resonance imaging ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,business.industry ,Term equivalent age ,05 social sciences ,Infant, Newborn ,Infant ,White Matter ,Very preterm ,Diffusion Tensor Imaging ,Neurology ,Child, Preschool ,Infant, Extremely Premature ,Female ,Prematurity ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
Very preterm-born infants are at risk of adverse neurodevelopmental outcomes. Brain magnetic resonance imaging (MRI) at term equivalent age (TEA) can probe tissue microstructure and morphology, and demonstrates potential in the early prediction of outcomes. In this study, we use the recently introduced fixel-based analysis method for diffusion MRI to investigate the association between microstructure and morphology at TEA, and motor and cognitive development at 1 and 2 years corrected age (CA). Eighty infants born
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- 2019
14. Correlated Resting-State Functional MRI Activity of Frontostriatal, Thalamic, Temporal, and Cerebellar Brain Regions Differentiates Stroke Survivors with High Compared to Low Depressive Symptom Scores
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Stephen E. Rose, Graeme J. Hankey, Bruce C.V. Campbell, Tamara Tse, Rishma Vidyasagar, Gemma Lamp, Leeanne M. Carey, Stephen M. Davis, Geoffrey A. Donnan, Henry Ma, David W. Howells, Alan Connelly, and Peter Goodin
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Male ,medicine.medical_specialty ,Article Subject ,Brain activity and meditation ,Audiology ,Brain mapping ,Severity of Illness Index ,050105 experimental psychology ,Temporal lobe ,lcsh:RC321-571 ,Diagnosis, Differential ,03 medical and health sciences ,0302 clinical medicine ,Severity of illness ,medicine ,Humans ,0501 psychology and cognitive sciences ,Survivors ,Stroke ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Depression (differential diagnoses) ,Default mode network ,Aged ,Uncategorized ,Brain Mapping ,Resting state fMRI ,business.industry ,Depression ,05 social sciences ,Brain ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Cross-Sectional Studies ,Neurology ,Female ,Neurology (clinical) ,business ,030217 neurology & neurosurgery ,Research Article - Abstract
Background.One in three survivors of stroke experience poststroke depression (PSD). PSD has been linked with poorer recovery of function and cognition, yet our understanding of potential mechanisms is currently limited. Alterations in resting-state functional MRI have been investigated to a limited extent. Fluctuations in low frequency signal are reported, but it is unknown if interactions are present between the level of depressive symptom score and intrinsic brain activity in varying brain regions.Objective.To investigate potential interaction effects between whole-brain resting-state activity and depressive symptoms in stroke survivors with low and high levels of depressive symptoms.Methods.A cross-sectional analysis of 63 stroke survivors who were assessed at 3 months poststroke for depression, using the Montgomery–Åsberg Depression Rating Scale (MÅDRS-SIGMA), and for brain activity using fMRI. A MÅDRS-SIGMA score of >8 was classified as high depressive symptoms. Fractional amplitude of frequency fluctuations (fALFF) data across three frequency bands (broadband, i.e., ~0.01–0.08; subbands, i.e., slow-5: ~0.01–0.027 Hz, slow-4: 0.027–0.07) was examined.Results.Of the 63 stroke survivors, 38 were classified as “low-depressive symptoms” and 25 as “high depressive symptoms.” Six had a past history of depression. We found interaction effects across frequency bands in several brain regions that differentiated the two groups. The broadband analysis revealed interaction effects in the left insula and the left superior temporal lobe. The subband analysis showed contrasting fALFF response between the two groups in the left thalamus, right caudate, and left cerebellum. Across the three frequency bands, we found contrasting fALFF response in areas within the fronto-limbic-thalamic network and cerebellum.Conclusions.We provide evidence that fALFF is sensitive to changes in poststroke depressive symptom severity and implicates frontostriatal and cerebellar regions, consistent with previous studies. The use of multiband analysis could be an effective method to examine neural correlates of depression after stroke. The START-PrePARE trial is registered with the Australian New Zealand Clinical Trial Registry, numberACTRN12610000987066.
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- 2019
15. Extent of altered white matter in unilateral and bilateral periventricular white matter lesions in children with unilateral cerebral palsy
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Stephen E. Rose, Kerstin Pannek, Simon M Scheck, Jurgen Fripp, Roslyn N. Boyd, Lee B. Reid, and Simona Fiori
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Male ,Adolescent ,Leukomalacia, Periventricular ,Pyramidal Tracts ,Functional Laterality ,Cerebral palsy ,White matter ,Thalamus ,Neural Pathways ,Fractional anisotropy ,Developmental and Educational Psychology ,medicine ,Humans ,Child ,Cerebral Palsy ,Brain ,Anatomy ,medicine.disease ,White Matter ,Hyperintensity ,Clinical Psychology ,Diffusion Magnetic Resonance Imaging ,medicine.anatomical_structure ,Hemiparesis ,Corticospinal tract ,Periventricular white matter lesions ,Anisotropy ,Female ,medicine.symptom ,Psychology ,Diffusion MRI - Abstract
Aims To investigate the extent of white matter damage in children with unilateral cerebral palsy (UCP) caused by periventricular white matter lesions comparing between unilateral and bilateral lesions; and to investigate a relationship between white matter microstructure and hand function. Methods and procedures Diffusion MRI images from 46 children with UCP and 18 children with typical development (CTD) were included. Subjects were grouped by side of hemiparesis and unilateral or bilateral lesions. A voxel-wise white matter analysis was performed to identify regions where fractional anisotropy (FA) was significantly different between UCP groups and CTD; and where FA correlated with either dominant or impaired hand function (using Jebsen Taylor Hand Function Test). Outcomes and results Children with unilateral lesions had reduced FA in the corticospinal tract of the affected hemisphere. Children with bilateral lesions had widespread reduced FA extending into all lobes. In children with left hemiparesis, impaired hand function correlated with FA in the contralateral corticospinal tract. Dominant hand function correlated with FA in the posterior thalamic radiations as well as multiple other regions in both left and right hemiparesis groups. Conclusions and implications Periventricular white matter lesions consist of focal and diffuse components. Focal lesions may cause direct motor fibre insult resulting in motor impairment. Diffuse white matter injury is heterogeneous, and may contribute to more global dysfunction. What this paper adds Focal white matter alterations are observed in the corticospinal tract in UCP with unilateral white matter lesions Diffuse white matter alterations throughout all cerebral lobes are observed in UCP with bilateral white matter lesions Fractional anisotropy in the posterior thalamic radiations correlates with dominant hand function
- Published
- 2016
16. Relationship Between Diffusion Tensor Imaging (DTI) Findings and Cognition Following Pediatric TBI: A Meta-Analytic Review
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Rachel M. Roberts, Stephen E. Rose, and Jane L. Mathias
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Male ,medicine.medical_specialty ,Traumatic brain injury ,Poison control ,Severity of Illness Index ,Article ,050105 experimental psychology ,White matter ,03 medical and health sciences ,Cognition ,0302 clinical medicine ,Physical medicine and rehabilitation ,Brain Injuries, Traumatic ,Severity of illness ,Fractional anisotropy ,Developmental and Educational Psychology ,medicine ,Humans ,Effective diffusion coefficient ,0501 psychology and cognitive sciences ,Child ,Psychiatry ,05 social sciences ,Brain ,Original Articles ,medicine.disease ,White Matter ,Diffusion Tensor Imaging ,Neuropsychology and Physiological Psychology ,medicine.anatomical_structure ,Brain Injuries ,Anisotropy ,Female ,Cognition Disorders ,Psychology ,030217 neurology & neurosurgery ,Diffusion MRI - Abstract
This study meta-analyzed research examining relationships between diffusion tensor imaging and cognition following pediatric traumatic brain injury (TBI). Data from 14 studies that correlated fractional anisotropy (FA) or apparent diffusion coefficient/mean diffusivity with cognition were analyzed. Short-term (
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- 2016
17. Automated, quantitative measures of grey and white matter lesion burden correlates with motor and cognitive function in children with unilateral cerebral palsy
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Stephen E. Rose, Andrew P. Bradley, Alex M. Pagnozzi, Nicholas Dowson, Roslyn N. Boyd, Simona Fiori, and James D. Doecke
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Male ,Pathology ,Movement disorders ,Neuropsychological Tests ,Severity of Illness Index ,lcsh:RC346-429 ,Functional Laterality ,030218 nuclear medicine & medical imaging ,0302 clinical medicine ,Nuclear Medicine and Imaging ,Image Processing, Computer-Assisted ,Child ,Movement Disorders ,medicine.diagnostic_test ,Brain lesion ,Cerebral palsy ,Magnetic resonance imaging ,Neurology (clinical) ,Radiology ,Cognitive Neuroscience ,Neurology ,Brain ,Regular Article ,Neuropsychological test ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,lcsh:R858-859.7 ,Regression Analysis ,Female ,medicine.symptom ,Psychology ,Algorithms ,medicine.medical_specialty ,Adolescent ,Grey matter ,Cognitive neuroscience ,lcsh:Computer applications to medicine. Medical informatics ,White matter ,Lesion ,03 medical and health sciences ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,lcsh:Neurology. Diseases of the nervous system ,Cerebral Palsy ,medicine.disease ,Cognition Disorders ,030217 neurology & neurosurgery - Abstract
White and grey matter lesions are the most prevalent type of injury observable in the Magnetic Resonance Images (MRIs) of children with cerebral palsy (CP). Previous studies investigating the impact of lesions in children with CP have been qualitative, limited by the lack of automated segmentation approaches in this setting. As a result, the quantitative relationship between lesion burden has yet to be established. In this study, we perform automatic lesion segmentation on a large cohort of data (107 children with unilateral CP and 18 healthy children) with a new, validated method for segmenting both white matter (WM) and grey matter (GM) lesions. The method has better accuracy (94%) than the best current methods (73%), and only requires standard structural MRI sequences. Anatomical lesion burdens most predictive of clinical scores of motor, cognitive, visual and communicative function were identified using the Least Absolute Shrinkage and Selection operator (LASSO). The improved segmentations enabled identification of significant correlations between regional lesion burden and clinical performance, which conform to known structure-function relationships. Model performance was validated in an independent test set, with significant correlations observed for both WM and GM regional lesion burden with motor function (p, Graphical abstract Image 1, Highlights • Presents an automated lesion segmentation approach tailored to cerebral palsy • Demonstrates the utility of quantifying lesions from MRI • Illustrates the influence that grey matter lesions have on functional impairments
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- 2016
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18. Blood–brain barrier dysfunction following traumatic brain injury: correlation of Ktrans(DCE-MRI) and SUVR (99mTc-DTPA SPECT) but not serum S100B
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David Macfarlane, John Cardinal, Timothy Whyte, Christopher Bell, Stephen E. Rose, and Craig Winter
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Traumatic brain injury ,99mtc dtpa ,Contrast Media ,Poison control ,S100 Calcium Binding Protein beta Subunit ,Positive correlation ,Blood–brain barrier ,Severity of Illness Index ,Correlation ,Young Adult ,Patient age ,Transfer constant ,medicine ,Humans ,Prospective Studies ,Aged ,Tomography, Emission-Computed, Single-Photon ,business.industry ,Brain ,Organotechnetium Compounds ,General Medicine ,Middle Aged ,Pentetic Acid ,medicine.disease ,Magnetic Resonance Imaging ,Surgery ,medicine.anatomical_structure ,Neurology ,Blood-Brain Barrier ,Brain Injuries ,Female ,Neurology (clinical) ,Radiopharmaceuticals ,business ,Nuclear medicine - Abstract
Damage to the blood-brain barrier (BBB) is an important secondary mechanism that occurs following traumatic brain injury (TBI) and may provide a potential therapeutic target to improve patient outcome. For such a progress to be realised, an accurate assessment of BBB compromise needs to be established.Fourteen patients with TBI were prospectively recruited. Post-traumatic BBB dysfunction was assessed using dynamic contrast-enhanced MRI (DCE-MRI), single-photon emission computerised tomography (SPECT) and serum S100B levels.A statistically significant correlation between standardised uptake value ratio (SUVR) calculated from 99mTc-DTPA SPECT and K(trans) (a volume transfer constant) from DCE-MRI was found for those eight patients who had concurrent scans. The positive correlation persisted when the data were corrected for patient age, number of days following trauma and both parameters combined. We found no statistically significant correlation between either of the imaging modalities and concurrent serum S100B levels.The correlation of SPECT with DCE-MRI suggests that either scan may be used to assess post-traumatic BBB damage. We could not support serum S100B to be an accurate measure of BBB damage when sampled a number of days following injury but the small number of patients, the heterogeneity in TBI patients and the delay following injury makes any firm conclusions regarding S100B and BBB difficult.
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- 2015
19. Corticopontocerebellar Connectivity Disruption in Congenital Hemiplegia
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Stephen E. Rose, Andrea Guzzetta, Roslyn N. Boyd, Robert S. Ware, Kerstin Pannek, Rosa Pasquariello, Simona Fiori, and Giovanni Cioni
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congenital hemiplegia ,Male ,Cerebellum ,Adolescent ,Hemiplegia ,Severity of Illness Index ,Region of interest ,Image Interpretation, Computer-Assisted ,Neural Pathways ,medicine ,Humans ,hand function ,Child ,Congenital hemiplegia ,crossed cerebellar diaschisis ,Cerebral Cortex ,Hand function ,cerebrocerebellar connectivity ,medicine.diagnostic_test ,Cerebrum ,Cerebral Palsy ,Functional connectivity ,Rehabilitation ,Magnetic resonance imaging ,General Medicine ,cerebellum ,Neurology (clinical) ,Neurology ,Hand ,Magnetic Resonance Imaging ,Crossed cerebellar diaschisis ,medicine.anatomical_structure ,Case-Control Studies ,Female ,Psychology ,Neuroscience - Abstract
Background. Crossed cerebellar diaschisis is the disruption of functional connectivity between cerebrum and cerebellum after hemispheric unilateral brain lesions. In adults and to a lesser extent in children, crossed cerebellar diaschisis has been largely investigated by functional connectivity and demonstrated to influence paretic hand function. Objective. We aim to demonstrate a disruption in structural corticopontocerebellar (CPC) connectivity in children with congenital brain lesions and examine its correlation with paretic hand motor function. Methods. Thirty-six children (Manual Ability Classification System: I, n = 21; II, n = 15) with unilateral brain lesions and 18 controls were analyzed in a case-control study, and diffusion magnetic resonance imaging data were acquired at 3T. High angular resolution diffusion imaging probabilistic tractography was employed for the region of interest–based reconstruction of CPC tracts. To identify statistical differences in structural cerebrocerebellar connectivity between case and control groups, an asymmetry index based on the number of streamlines of CPC tracts was used. In the case group, the correlation between asymmetry index and hand function measures was also determined. Results. Projections through the middle cerebellar peduncle to the contralateral cerebral cortex showed greater asymmetry in children with congenital unilateral brain lesion compared to controls ( P = .03), thus indicating a disruption of structural cerebrocerebellar connectivity. The degree of asymmetry index showed a correlation ( P < .03; r = −0.31) with impaired hand abilities in bimanual tasks. Conclusions. Disruption of structural cerebrocerebellar connectivity is present in patients with congenital unilateral brain injury and might be related to impaired hand function in bimanual skills, with potential implication in tailoring early intervention strategies.
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- 2015
20. Basal forebrain atrophy correlates with amyloid β burden in Alzheimer's disease
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Stephen E. Rose, Georg M. Kerbler, Victor L. Villemagne, Olivier Salvado, Elizabeth J. Coulson, Juergen Fripp, and Christopher C. Rowe
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Male ,Pathology ,aMCI, amnestic mild cognitive impairment ,CSF, cerebrospinal fluid ,lcsh:RC346-429 ,chemistry.chemical_compound ,0302 clinical medicine ,0303 health sciences ,Basal forebrain ,biology ,Regular Article ,SyN, symmetric normalization ,Alzheimer's disease ,HC, healthy control ,SUVR, standard uptake value ratio ,Aβ, amyloid-beta ,PiB, Pittsburgh compound B ,medicine.anatomical_structure ,Neurology ,MCI, mild cognitive impairment ,Disease Progression ,lcsh:R858-859.7 ,Female ,AD, Alzheimer's disease ,Psychology ,Alzheimer's Disease Neuroimaging Initiative ,medicine.medical_specialty ,Amyloid ,Basal Forebrain ,Amyloid beta ,Cognitive Neuroscience ,MNI, Montreal Neurological Institute ,lcsh:Computer applications to medicine. Medical informatics ,AIBL, Australian Imaging, Biomarkers and Lifestyle Flagship Study of Aging ,PET, positron emission tomography ,White matter ,03 medical and health sciences ,Atrophy ,Magnetic resonance imaging ,Alzheimer Disease ,3D, 3-dimensional ,Image Interpretation, Computer-Assisted ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Cognitive Dysfunction ,Cholinergic neuron ,WM, white matter ,TG-ROC, two-graph receiver operating characteristic ,lcsh:Neurology. Diseases of the nervous system ,030304 developmental biology ,Aged ,MPM, maximum probability maps ,Amyloid beta-Peptides ,SPSS, statistics software package for the social sciences ,medicine.disease ,OR, odds ratio ,ADNI, Alzheimer's Disease Neuroimaging Initiative ,PET ,chemistry ,MPRAGE, magnetization prepared rapid gradient echo ,T1W, T1-weighted ,Positron-Emission Tomography ,biology.protein ,GM, gray matter ,Neurology (clinical) ,Pittsburgh compound B ,MRI, magnetic resonance imaging ,030217 neurology & neurosurgery - Abstract
The brains of patients suffering from Alzheimer's disease (AD) have three classical pathological hallmarks: amyloid-beta (Aβ) plaques, tau tangles, and neurodegeneration, including that of cholinergic neurons of the basal forebrain. However the relationship between Aβ burden and basal forebrain degeneration has not been extensively studied. To investigate this association, basal forebrain volumes were determined from magnetic resonance images of controls, subjects with amnestic mild cognitive impairment (aMCI) and AD patients enrolled in the longitudinal Alzheimer's Disease Neuroimaging Initiative (ADNI) and Australian Imaging, Biomarkers and Lifestyle (AIBL) studies. In the AIBL cohort, these volumes were correlated within groups to neocortical gray matter retention of Pittsburgh compound B (PiB) from positron emission tomography images as a measure of Aβ load. The basal forebrain volumes of AD and aMCI subjects were significantly reduced compared to those of control subjects. Anterior basal forebrain volume was significantly correlated to neocortical PiB retention in AD subjects and aMCI subjects with high Aβ burden, whereas posterior basal forebrain volume was significantly correlated to neocortical PiB retention in control subjects with high Aβ burden. Therefore this study provides new evidence for a correlation between neocortical Aβ accumulation and basal forebrain degeneration. In addition, cluster analysis showed that subjects with a whole basal forebrain volume below a determined cut-off value had a 7 times higher risk of having a worse diagnosis within ~18 months., Highlights • The link between amyloid (Aβ) and basal forebrain degeneration in AD is unclear. • We find that basal forebrain volumes are correlated with neocortical Aβ burden. • Basal forebrain volume correlates with Aβ burden in at-risk control subjects. • Basal forebrain atrophy delineates subjects at increased risk of progressing to AD.
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- 2015
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21. Exposing asymmetric gray matter vulnerability in amyotrophic lateral sclerosis
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Kerstin Pannek, Alan Coulthard, Pamela A. McCombe, Robert D. Henderson, Stephen E. Rose, and Matthew S Devine
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Adult ,Male ,Weakness ,Pathology ,medicine.medical_specialty ,Limb dominance ,Cognitive Neuroscience ,lcsh:Computer applications to medicine. Medical informatics ,Somatosensory system ,computer.software_genre ,lcsh:RC346-429 ,VBM, voxel-based morphometry ,Atrophy ,Voxel ,Image Interpretation, Computer-Assisted ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Motor neuron disease ,Gray Matter ,Amyotrophic lateral sclerosis ,lcsh:Neurology. Diseases of the nervous system ,Aged ,UMN, upper motor neuron ,Brain ,Asymmetry ,Regular Article ,Voxel-based morphometry ,Anatomy ,Middle Aged ,ALS, amyotrophic lateral sclerosis ,medicine.disease ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Neurology ,GM, gray matter ,lcsh:R858-859.7 ,Upper limb ,Female ,LMN, lower motor neuron ,Neurology (clinical) ,medicine.symptom ,Psychology ,computer ,Motor cortex - Abstract
Limb weakness in amyotrophic lateral sclerosis (ALS) is typically asymmetric. Previous studies have identified an effect of limb dominance on onset and spread of weakness, however relative atrophy of dominant and non-dominant brain regions has not been investigated. Our objective was to use voxel-based morphometry (VBM) to explore gray matter (GM) asymmetry in ALS, in the context of limb dominance. 30 ALS subjects were matched with 17 healthy controls. All subjects were right-handed. Each underwent a structural MRI sequence, from which GM segmentations were generated. Patterns of GM atrophy were assessed in ALS subjects with first weakness in a right-sided limb (n = 15) or left-sided limb (n = 15). Within each group, a voxelwise comparison was also performed between native and mirror GM images, to identify regions of hemispheric GM asymmetry. Subjects with ALS showed disproportionate atrophy of the dominant (left) motor cortex hand area, irrespective of the side of first limb weakness (p, Highlights • GM asymmetry was assessed, using VBM, in right-handed ALS and control subjects. • The dominant motor hand area underwent disproportionate atrophy in ALS (p ≤ 0.01). • In subjects with dominant limb onset, there was greater atrophy of language areas. • A VBM asymmetry protocol is more sensitive than standard group comparisons. • Asymmetric vulnerability of cortical GM supports a role for brain development in the pathogenesis of ALS.
- Published
- 2015
22. Diffusion Tensor Imaging (DTI) Findings Following Pediatric Non-Penetrating TBI: A Meta-Analysis
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Jane L. Mathias, Stephen E. Rose, and Rachel M. Roberts
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Male ,Traumatic brain injury ,Wounds, Nonpenetrating ,Corpus callosum ,Severity of Illness Index ,Corpus Callosum ,White matter ,Predictive Value of Tests ,Fractional anisotropy ,Developmental and Educational Psychology ,medicine ,Humans ,Effective diffusion coefficient ,Child ,Trauma Severity Indices ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Original Articles ,medicine.disease ,Magnetic Resonance Imaging ,body regions ,Diffusion Tensor Imaging ,Neuropsychology and Physiological Psychology ,medicine.anatomical_structure ,Brain Injuries ,Predictive value of tests ,Anisotropy ,Female ,Nuclear medicine ,business ,Psychology ,Neuroscience ,Diffusion MRI - Abstract
This study meta-analyzed research examining Diffusion Tensor Imaging following pediatric non-penetrating traumatic brain injury to identify the location and extent of white matter changes. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) data from 20 studies were analyzed. FA increased and ADC decreased in most white matter tracts in the short-term (moderate-to-large effects), and FA decreased and ADC increased in the medium- to long-term (moderate-to-very-large effects). Whole brain (short-term), cerebellum and corpus callosum (medium- to long-term) FA values have diagnostic potential, but the impact of age/developmental stage and injury severity on FA/ADC, and the predictive value, is unclear.
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- 2014
23. Investigating brain connectivity heritability in a twin study using diffusion imaging data
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Greig I. de Zubicaray, Paul M. Thompson, Kaikai Shen, Jurgen Fripp, Nicholas G. Martin, Olivier Salvado, Katie L. McMahon, Margaret J. Wright, and Stephen E. Rose
- Subjects
Adult ,Male ,Cognitive Neuroscience ,Twins ,computer.software_genre ,Nerve Fibers, Myelinated ,Article ,White matter ,Young Adult ,Voxel ,Neural Pathways ,Fractional anisotropy ,medicine ,Humans ,Cerebral Cortex ,Orientation (computer vision) ,Heritability ,White Matter ,Twin study ,Diffusion imaging ,Diffusion Magnetic Resonance Imaging ,Diffusion Tensor Imaging ,medicine.anatomical_structure ,Neurology ,Female ,Nerve Net ,Psychology ,computer ,Neuroscience ,Diffusion MRI - Abstract
Heritability of brain anatomical connectivity has been studied with diffusion-weighted imaging (DWI) mainly by modeling each voxel's diffusion pattern as a tensor (e.g., to compute fractional anisotropy), but this method cannot accurately represent the many crossing connections present in the brain. We hypothesized that different brain networks (i.e., their component fibers) might have different heritability and we investigated brain connectivity using High Angular Resolution Diffusion Imaging (HARDI) in a cohort of twins comprising 328 subjects that included 70 pairs of monozygotic and 91 pairs of dizygotic twins. Water diffusion was modeled in each voxel with a Fiber Orientation Distribution (FOD) function to study heritability for multiple fiber orientations in each voxel. Precision was estimated in a test-retest experiment on a sub-cohort of 39 subjects. This was taken into account when computing heritability of FOD peaks using an ACE model on the monozygotic and dizygotic twins. Our results confirmed the overall heritability of the major white matter tracts but also identified differences in heritability between connectivity networks. Inter-hemispheric connections tended to be more heritable than intra-hemispheric and cortico-spinal connections. The highly heritable tracts were found to connect particular cortical regions, such as medial frontal cortices, postcentral, paracentral gyri, and the right hippocampus.
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- 2014
24. Identifying relevant biomarkers of brain injury from structural MRI: Validation using automated approaches in children with unilateral cerebral palsy
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James D. Doecke, Simona Fiori, Stephen E. Rose, Andrew P. Bradley, Alex M. Pagnozzi, Nicholas Dowson, and Roslyn N. Boyd
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Central Nervous System ,Male ,Vision ,Social Sciences ,lcsh:Medicine ,Pathology and Laboratory Medicine ,Biochemistry ,Nervous System ,030218 nuclear medicine & medical imaging ,Diagnostic Radiology ,Cohort Studies ,Families ,Automation ,0302 clinical medicine ,Medicine and Health Sciences ,Image Processing, Computer-Assisted ,Psychology ,Brain Damage ,Gray Matter ,Child ,lcsh:Science ,Children ,Cognitive Impairment ,Multidisciplinary ,medicine.diagnostic_test ,Cognitive Neurology ,Radiology and Imaging ,Cognition ,Magnetic Resonance Imaging ,White Matter ,medicine.anatomical_structure ,Neurology ,Child, Preschool ,Sensory Perception ,Female ,medicine.symptom ,Anatomy ,Cohort study ,Research Article ,medicine.medical_specialty ,Adolescent ,Imaging Techniques ,Cognitive Neuroscience ,Brain damage ,Grey matter ,Research and Analysis Methods ,Cerebral palsy ,White matter ,03 medical and health sciences ,Structure-Activity Relationship ,Physical medicine and rehabilitation ,Signs and Symptoms ,Neuroimaging ,Diagnostic Medicine ,medicine ,Humans ,business.industry ,Cerebral Palsy ,lcsh:R ,Biology and Life Sciences ,Reproducibility of Results ,Magnetic resonance imaging ,medicine.disease ,Age Groups ,Brain Injuries ,People and Places ,Physical therapy ,Lesions ,Cognitive Science ,Population Groupings ,lcsh:Q ,business ,030217 neurology & neurosurgery ,Biomarkers ,Neuroscience - Abstract
Previous studies have proposed that the early elucidation of brain injury from structural Magnetic Resonance Images (sMRI) is critical for the clinical assessment of children with cerebral palsy (CP). Although distinct aetiologies, including cortical maldevelopments, white and grey matter lesions and ventricular enlargement, have been categorised, these injuries are commonly only assessed in a qualitative fashion. As a result, sMRI remains relatively underexploited for clinical assessments, despite its widespread use. In this study, several automated and validated techniques to automatically quantify these three classes of injury were generated in a large cohort of children (n = 139) aged 5–17, including 95 children diagnosed with unilateral CP. Using a feature selection approach on a training data set (n = 97) to find severity of injury biomarkers predictive of clinical function (motor, cognitive, communicative and visual function), cortical shape and regional lesion burden were most often chosen associated with clinical function. Validating the best models on the unseen test data (n = 42), correlation values ranged between 0.545 and 0.795 (p
- Published
- 2017
25. Measuring neuroplasticity associated with cerebral palsy rehabilitation: An MRI based power analysis
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Nicholas Dowson, Lee B. Reid, Simona Fiori, Alex M. Pagnozzi, Roslyn N. Boyd, and Stephen E. Rose
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Male ,medicine.medical_specialty ,Adolescent ,050105 experimental psychology ,Cerebral palsy ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,Developmental Neuroscience ,Neuroimaging ,Fractional anisotropy ,Image Processing, Computer-Assisted ,medicine ,Humans ,0501 psychology and cognitive sciences ,Diffusion Tractography ,Child ,Neurorehabilitation ,Probability ,Cerebral Cortex ,Brain Mapping ,Neuronal Plasticity ,Cerebral Palsy ,05 social sciences ,medicine.disease ,Magnetic Resonance Imaging ,Diffusion Tensor Imaging ,Sample size determination ,Physical therapy ,Anisotropy ,Female ,Psychology ,030217 neurology & neurosurgery ,Developmental Biology ,Tractography ,Diffusion MRI - Abstract
Researchers in the field of child neurology are increasingly looking to supplement clinical trials of motor rehabilitation with neuroimaging in order to better understand the relationship between behavioural training, brain changes, and clinical improvements. Randomised controlled trials are typically accompanied by sample size calculations to detect clinical improvements but, despite the large cost of neuroimaging, not equivalent calculations for concurrently acquired imaging neuroimaging measures of changes in response to intervention. To aid in this regard, a power analysis was conducted for two measures of brain changes that may be indexed in a trial of rehabilitative therapy for cerebral palsy: cortical thickness of the impaired primary sensorimotor cortex, and fractional anisotropy of the impaired, delineated corticospinal tract. Power for measuring fractional anisotropy was assessed for both region-of-interest-seeded and fMRI-seeded diffusion tractography. Taking into account practical limitations, as well as data loss due to behavioural and image-processing issues, estimated required participant numbers were 101, 128 and 59 for cortical thickness, region-of-interest-based tractography, and fMRI-seeded tractography, respectively. These numbers are not adjusted for study attrition. Although these participant numbers may be out of reach of many trials, several options are available to improve statistical power, including careful preparation of participants for scanning using mock simulators, careful consideration of image processing options, and enrolment of as homogeneous a cohort as possible. This work suggests that smaller and moderate sized studies give genuine consideration to harmonising scanning protocols between groups to allow the pooling of data.
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- 2017
26. Lesion segmentation from multimodal MRI using random forest following ischemic stroke
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Bruce C.V. Campbell, Soren Christensen, Stephen E. Rose, Leeanne M. Carey, Susan Palmer, Olivier Salvado, Gagan Sharma, Jurgen Fripp, Alan Connelly, Pierrick Bourgeat, Soumya Ghose, and Jhimli Mitra
- Subjects
Adult ,Male ,medicine.medical_specialty ,Lesion Identification ,Cognitive Neuroscience ,Fluid-attenuated inversion recovery ,Brain Ischemia ,030218 nuclear medicine & medical imaging ,Lesion ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Effective diffusion coefficient ,Stroke ,Aged ,Aged, 80 and over ,medicine.diagnostic_test ,Cerebral infarction ,business.industry ,Bayes Theorem ,Magnetic resonance imaging ,Cerebral Infarction ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,White Matter ,Markov Chains ,Hyperintensity ,Diffusion Magnetic Resonance Imaging ,Neurology ,Female ,Radiology ,medicine.symptom ,business ,Algorithms ,030217 neurology & neurosurgery - Abstract
Understanding structure-function relationships in the brain after stroke is reliant not only on the accurate anatomical delineation of the focal ischemic lesion, but also on previous infarcts, remote changes and the presence of white matter hyperintensities. The robust definition of primary stroke boundaries and secondary brain lesions will have significant impact on investigation of brain-behavior relationships and lesion volume correlations with clinical measures after stroke. Here we present an automated approach to identify chronic ischemic infarcts in addition to other white matter pathologies, that may be used to aid the development of post-stroke management strategies. Our approach uses Bayesian-Markov Random Field (MRF) classification to segment probable lesion volumes present on fluid attenuated inversion recovery (FLAIR) MRI. Thereafter, a random forest classification of the information from multimodal (T1-weighted, T2-weighted, FLAIR, and apparent diffusion coefficient (ADC)) MRI images and other context-aware features (within the probable lesion areas) was used to extract areas with high likelihood of being classified as lesions. The final segmentation of the lesion was obtained by thresholding the random forest probabilistic maps. The accuracy of the automated lesion delineation method was assessed in a total of 36 patients (24 male, 12 female, mean age: 64.57±14.23yrs) at 3months after stroke onset and compared with manually segmented lesion volumes by an expert. Accuracy assessment of the automated lesion identification method was performed using the commonly used evaluation metrics. The mean sensitivity of segmentation was measured to be 0.53±0.13 with a mean positive predictive value of 0.75±0.18. The mean lesion volume difference was observed to be 32.32%±21.643% with a high Pearson's correlation of r=0.76 (p
- Published
- 2014
27. Quantitative comparison of cortical and deep grey matter in pathological subtypes of unilateral cerebral palsy
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Simona Fiori, Simon M Scheck, Roslyn N. Boyd, Stephen E. Rose, and Kerstin Pannek
- Subjects
Male ,Adolescent ,Leukomalacia, Periventricular ,Thalamus ,Hemiplegia ,Grey matter ,Globus Pallidus ,computer.software_genre ,Severity of Illness Index ,Functional Laterality ,Cerebral palsy ,Developmental Neuroscience ,Voxel ,medicine ,Humans ,Child ,Cerebrum ,Cerebral Cortex ,medicine.diagnostic_test ,Cerebral Palsy ,Putamen ,Magnetic resonance imaging ,Gross Motor Function Classification System ,Anatomy ,medicine.disease ,Magnetic Resonance Imaging ,Cross-Sectional Studies ,Globus pallidus ,medicine.anatomical_structure ,Child, Preschool ,Pediatrics, Perinatology and Child Health ,Female ,Neurology (clinical) ,Psychology ,computer - Abstract
Aim The aim of this study was to quantify grey matter changes in children with unilateral cerebral palsy (UCP), differentiating between cortical or deep grey matter (CDGM) lesions, periventricular white matter (PWM) lesions, and unilateral and bilateral lesions. Method In a cross-sectional study we obtained high resolution structural magnetic resonance images from 72 children (41 males, 31 females, mean age 10y 9mo [SD 3y 1mo], range 5y 1mo–17y 1mo) with UCP (33 left, 39 right hemiplegia; Manual Ability Classification System level I n=29, II n=43; Gross Motor Function Classification System level I n=46, II n=26), and 19 children with typical development (CTD; eight males, 11 females, mean age 11y 2mo [SD 2y 7mo], range 7y 8mo–16y 4mo). Images were classified by lesion type and analyzed using voxel-based morphometry (VBM) and subcortical volumetric analysis. Results Deep grey matter volumes were not significantly different between children with CDGM and PWM lesions, with the thalamus, putamen, and globus pallidus being reduced unilaterally in both groups compared with CTD (p≤0.001). Children with CDGM lesions additionally showed widespread cortical changes involving all lobes using VBM (p
- Published
- 2014
28. Reliability of a novel, semi-quantitative scale for classification of structural brain magnetic resonance imaging in children with cerebral palsy
- Author
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Katrjin Klingels, Hilde Feys, Leen Van Gestel, Els Ortibus, Stephen E. Rose, Andrea Guzzetta, Giovanni Cioni, Simona Fiori, and Roslyn N. Boyd
- Subjects
Male ,medicine.medical_specialty ,Adolescent ,diagnosis/pathology ,Brain Structure and Function ,Corpus callosum ,Severity of Illness Index ,Cerebral palsy ,Developmental Neuroscience ,Rating scale ,medicine ,Humans ,Preschool ,Child ,Reliability (statistics) ,medicine.diagnostic_test ,business.industry ,Cerebral Palsy ,Brain ,Reproducibility of Results ,Magnetic resonance imaging ,Gross Motor Function Classification System ,Intra-rater reliability ,medicine.disease ,Magnetic Resonance Imaging ,Surgery ,Adolescent, Brain ,pathology, Cerebral Palsy ,diagnosis/pathology, Child, Child ,Preschool, Female, Humans, Magnetic Resonance Imaging, Male, Reproducibility of Results, Severity of Illness Index ,Child, Preschool ,Pediatrics, Perinatology and Child Health ,pathology ,Female ,Neurology (clinical) ,Psychology ,Nuclear medicine ,business - Abstract
Aim To describe the development of a novel rating scale for classification of brain structural magnetic resonance imaging (MRI) in children with cerebral palsy (CP) and to assess its interrater and intrarater reliability. Method The scale consists of three sections. Section 1 contains descriptive information about the patient and MRI. Section 2 contains the graphical template of brain hemispheres onto which the lesion is transposed. Section 3 contains the scoring system for the quantitative analysis of the lesion characteristics, grouped into different global scores and subscores that assess separately side, regions, and depth. A larger interrater and intrarater reliability study was performed in 34 children with CP (22 males, 12 females; mean age at scan of 9y 5mo [SD 3y 3mo], range 4y–16y 11mo; Gross Motor Function Classification System level I, [n=22], II [n=10], and level III [n=2]). Results Very high interrater and intrarater reliability of the total score was found with indices above 0.87. Reliability coefficients of the lobar and hemispheric subscores ranged between 0.53 and 0.95. Global scores for hemispheres, basal ganglia, brain stem, and corpus callosum showed reliability coefficients above 0.65. Interpretation This study presents the first visual, semi-quantitative scale for classification of brain structural MRI in children with CP. The high degree of reliability of the scale supports its potential application for investigating the relationship between brain structure and function and examining treatment response according to brain lesion severity in children with CP.
- Published
- 2014
29. Distance informed Track-Weighted Imaging (diTWI): A framework for sensitising streamline information to neuropathology
- Author
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Yaniv Gal, Kerstin Pannek, Stuart Crozier, Michael Fay, Paul Thomas, Stephen E. Rose, Pierrick Bourgeat, Alan Coulthard, Christopher Bell, and Olivier Salvado
- Subjects
Male ,Computer science ,Cognitive Neuroscience ,Neuropathology ,Astrocytoma ,Fluid-attenuated inversion recovery ,computer.software_genre ,Nerve Fibers, Myelinated ,Sensitivity and Specificity ,Pattern Recognition, Automated ,White matter ,Region of interest ,Voxel ,Glioma ,Image Interpretation, Computer-Assisted ,Fractional anisotropy ,medicine ,Humans ,Aged ,Aged, 80 and over ,Voxel intensity ,medicine.diagnostic_test ,Brain Neoplasms ,business.industry ,Reproducibility of Results ,Pattern recognition ,Middle Aged ,Image Enhancement ,medicine.disease ,Diffusion Tensor Imaging ,medicine.anatomical_structure ,Neurology ,Positron emission tomography ,Dynamic contrast-enhanced MRI ,Artificial intelligence ,business ,Nuclear medicine ,computer ,Algorithms ,Tractography ,Diffusion MRI ,Anaplastic astrocytoma ,Glioblastoma - Abstract
Track-Weighted Imaging (TWI), where voxel intensity is based on image metrics encoded along streamline trajectories, provides a mechanism to study white matter disease. However, with generalised streamline weighting, it is difficult to localise the precise anatomical source and spread of injury or neuropathology. This limitation can be overcome by modulating the voxel weight based on the distance of the voxel from a given anatomical location along the tract, which we term diTWI: distance informed Track-Weighted Imaging. The location of known neuropathology can be delineated on any given imaging modality (e.g. MRI or PET). To demonstrate the clinical utility of this approach, we measured tumour cell infiltration along WM fibre tracts in 13 patients with newly diagnosed glioblastoma and 1 patient with Anaplastic Astrocytoma. TWI and diTWI maps were generated using information obtained from dynamic contrast enhanced MRI (area under the curve, AUC) and diffusivity maps (ADC and FA) with tumour boundaries automatically extracted using a logistic regression classifier. The accuracy of the derived tumour volumes was compared to those generated using 3,4-dihydroxy-6-[(18)F]-fluoro-l-phenylalanine (FDOPA) PET imaging. The accuracy of the tumour volumes generated from the diTWI maps was superior to volumes derived from the TWI, geometric distance or baseline AUC, FA and ADC maps. The relative overlap and relative dissimilarity rates for the diTWI generated tumour volumes after classification were found to be 82.3±15.3% (range 69.1-91.9) and 16.9±8.8% (range 7.9-37.5), respectively. These findings show that diTWI maps provide a useful framework for localising neuropathological processes occurring along WM pathways.
- Published
- 2014
30. Assessment of the structural brain network reveals altered connectivity in children with unilateral cerebral palsy due to periventricular white matter lesions
- Author
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Andrea Guzzetta, Stephen E. Rose, Roslyn N. Boyd, Simona Fiori, and Kerstin Pannek
- Subjects
Male ,Congenital hemiplegia ,Pathology ,FMAM, fit model to all measurements ,lcsh:RC346-429 ,FA, fractional anisotropy ,Child ,AHA, assisting hand assessment ,Brain network ,Brain ,DROP-R, detection and replacement of outliers prior to resampling ,GMFCS, gross motor function classification system ,Magnetic Resonance Imaging ,White Matter ,Unilateral cerebral palsy ,medicine.anatomical_structure ,Neurology ,Child, Preschool ,Periventricular white matter lesions ,Connectome ,lcsh:R858-859.7 ,Female ,Psychology ,Tractography ,medicine.medical_specialty ,Adolescent ,Leukomalacia, Periventricular ,Cognitive Neuroscience ,lcsh:Computer applications to medicine. Medical informatics ,Article ,Diffusion MRI ,Cerebral palsy ,White matter ,CTD, children with typical development ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,CDGM, cortical and deep grey matter ,CP, cerebral palsy ,NBS, network based statistic ,lcsh:Neurology. Diseases of the nervous system ,MACS, manual ability classification system ,HARDI, high angular resolution diffusion imaging ,Cerebral Palsy ,HOMOR, higher order model outlier rejection ,PWM, periventricular white matter ,medicine.disease ,Sensory function ,Neurology (clinical) ,Nerve Net ,Neuroscience - Abstract
Background Cerebral palsy (CP) is a term to describe the spectrum of disorders of impaired motor and sensory function caused by a brain lesion occurring early during development. Diffusion MRI and tractography have been shown to be useful in the study of white matter (WM) microstructure in tracts likely to be impacted by the static brain lesion. Aim The purpose of this study was to identify WM pathways with altered connectivity in children with unilateral CP caused by periventricular white matter lesions using a whole-brain connectivity approach. Methods Data of 50 children with unilateral CP caused by periventricular white matter lesions (5–17 years; manual ability classification system [MACS] I = 25/II = 25) and 17 children with typical development (CTD; 7–16 years) were analysed. Structural and High Angular Resolution Diffusion weighted Images (HARDI; 64 directions, b = 3000 s/mm2) were acquired at 3 T. Connectomes were calculated using whole-brain probabilistic tractography in combination with structural parcellation of the cortex and subcortical structures. Connections with altered fractional anisotropy (FA) in children with unilateral CP compared to CTD were identified using network-based statistics (NBS). The relationship between FA and performance of the impaired hand in bimanual tasks (Assisting Hand Assessment—AHA) was assessed in connections that showed significant differences in FA compared to CTD. Results FA was reduced in children with unilateral CP compared to CTD. Seven pathways, including the corticospinal, thalamocortical, and fronto-parietal association pathways were identified simultaneously in children with left and right unilateral CP. There was a positive relationship between performance of the impaired hand in bimanual tasks and FA within the cortico-spinal and thalamo-cortical pathways (r2 = 0.16–0.44; p, Highlights • Alterations in FA in children with CP were assessed using the connectome approach. • FA is reduced in corticospinal, thalamocortical, and association tracts in CP. • Higher FA is associated with better performance in bimanual tasks.
- Published
- 2014
31. Midsagittal corpus callosum area and conversion to multiple sclerosis after clinically isolated syndrome: A multicentre Australian cohort study
- Author
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Steve Simpson, Keith Dear, Cara Odenthal, Alan Coulthard, Robyn M. Lucas, Ingrid van der Mei, Stephen E. Rose, Bruce V. Taylor, Justin Oughton, Jurgen Fripp, and Anne-Louise Ponsonby
- Subjects
Adult ,Male ,Pathology ,medicine.medical_specialty ,Multiple Sclerosis ,Corpus callosum ,Corpus Callosum ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Atrophy ,Risk Factors ,Image Interpretation, Computer-Assisted ,parasitic diseases ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Longitudinal Studies ,Cerebral atrophy ,Clinically isolated syndrome ,medicine.diagnostic_test ,Surrogate endpoint ,business.industry ,Multiple sclerosis ,fungi ,Australia ,Magnetic resonance imaging ,medicine.disease ,Magnetic Resonance Imaging ,Oncology ,Disease Progression ,cardiovascular system ,Female ,Radiology ,business ,030217 neurology & neurosurgery ,Demyelinating Diseases ,Cohort study - Abstract
Introduction: Patients presenting with clinically isolated syndrome (CIS) may proceed to clinically definite multiple sclerosis (CDMS). Midsagittal corpus callosum area (CCA) is a surrogate marker for callosal atrophy, and can be obtained from a standard MRI study. This study explores the relationship between CCA measured at CIS presentation (baseline) and at 5 years post presentation, with conversion from CIS to CDMS. The association between CCA and markers of disability progression is explored. Methods: Corpus callosum area was measured on MRI scans at presentation and 5‐year review following diagnosis of a first demyelinating event, or evidence of progressive MS, in 143 participants in the Ausimmune/AusLong Study. Relationships between CCA (at baseline and follow‐up) and clinical outcomes were assessed. Results: Mean CCA at baseline study was 6.63 cm2 (SD 1.01). Patients who converted to MS by 5‐year review (n = 100) had a significantly smaller mean CCA at follow‐up (6.22 vs. 6.74, P = 0.007). Greater CCA reduction was associated with higher annualized relapse rate over follow‐up. Conclusion: Baseline CCA obtained from standard MRI protocols may be compared with subsequent MRI examinations as a surrogate for neurodegeneration and cerebral atrophy in patients with MS. This study demonstrates an association between CCA and disability in individuals presenting with CIS who convert to MS.
- Published
- 2016
32. Changes in the integrity of thalamocortical connections are associated with sensorimotor deficits in children with congenital hemiplegia
- Author
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Henry Tsao, Kerstin Pannek, Roslyn N. Boyd, and Stephen E. Rose
- Subjects
Male ,medicine.medical_specialty ,Histology ,Neurology ,Adolescent ,Developmental Disabilities ,Thalamus ,Severity of Illness Index ,Brain mapping ,Cerebral palsy ,Neural Pathways ,Fractional anisotropy ,Image Processing, Computer-Assisted ,medicine ,Humans ,Child ,Paracentral lobule ,Brain Mapping ,medicine.diagnostic_test ,Cerebral Palsy ,General Neuroscience ,Magnetic resonance imaging ,Anatomy ,medicine.disease ,Magnetic Resonance Imaging ,Diffusion Magnetic Resonance Imaging ,Child, Preschool ,Female ,Sensorimotor Cortex ,Psychology ,Neuroscience ,Diffusion MRI - Abstract
Preservation of thalamocortical projections to the sensorimotor cortex is related to improved hand function in children with cerebral palsy (CP). Whether CP is associated with altered microstructure of these sensorimotor projections or other thalamocortical pathways remains unclear. Forty-two children with congenital hemiplegia and fifteen typically developing children (TDC) underwent structural and diffusion-weighted imaging (high-angular-resolution diffusion imaging) using a 3T MRI. Structural T1-images were parcellated into 34 cortical regions and the thalamus per hemisphere. Thalamocortical projections were extracted using probabilistic tractography and the top tan cortical regions with the greatest number of thalamocortical streamlines for the TDC group were selected for further analysis. The thalamus was parcellated based on its cortical connections. Differences between hemispheres for thalamocortical streamline numbers to each cortical region [asymmetry index (AI)], tract volume and tract microstructure [weighted mean fractional anisotropy (FA) and mean diffusivity (MD)] were calculated. Correlations between these measures (AI, FA and MD) and sensorimotor function were performed. Thalamocortical projections showed topographical organisation based on cortical connectivity. Projections to paracentral lobule, pre-central and post-central gyri showed greater AI in CP group, which indicates reduced streamlines on the ipsilesioned hemisphere. Reduced FA, reduced tract volume and increased MD were also found for these thalamocortical projections on the ipsilesioned hemisphere in children with CP. Changes in AI and tract microstructure of these projections were associated with poorer sensorimotor function. The findings suggest CP is associated with reorganisation of thalamocortical projections to the sensorimotor cortex. Integrity in these projections may underpin deficits in sensorimotor function.
- Published
- 2013
33. Correlation of Adrenomedullin gene expression in peripheral blood leukocytes with severity of ischemic stroke
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Stephen E. Rose, Judith M. Greer, Stephen J. Read, Jia Liu, Pamela A. McCombe, Jun Yan, Alan Coulthard, and Robert D. Henderson
- Subjects
Adult ,Male ,medicine.medical_specialty ,Amylin ,Calcitonin gene-related peptide ,Severity of Illness Index ,Brain Ischemia ,Brain ischemia ,Adrenomedullin ,Young Adult ,Modified Rankin Scale ,Internal medicine ,Severity of illness ,Leukocytes ,medicine ,Humans ,cardiovascular diseases ,Aged ,Aged, 80 and over ,business.industry ,General Neuroscience ,General Medicine ,Middle Aged ,Hypoxia (medical) ,medicine.disease ,Up-Regulation ,Stroke ,Endocrinology ,Calcitonin ,Case-Control Studies ,Female ,medicine.symptom ,business ,Biomarkers - Abstract
Human adrenomedullin (ADM), a 52-amino acid peptide, belongs to the calcitonin/calcitonin gene-related peptide (CGRP)/amylin peptide family. ADM acts as a multifunctional regulatory peptide and is upregulated in response to hypoxia. Previous microarray studies have found increased ADM gene (ADM) expression in peripheral blood cells of patients with stroke, however, it is unknown if an increased ADM level is correlated with severity of human ischemic stroke. This study investigated ADM expression in peripheral blood leukocytes (PBL) of healthy controls and subjects at day 1, week 1 and week 3 postacute ischemic stroke using rtPCR methodology. We found that ADM expression was significantly upregulated on the first day of stroke compared to the healthy subjects and the disease controls; the levels remained elevated for up to week 3. Further, ADM expression at day 1 was correlated with stroke severity measured by the National Institute of Healthy Stroke Scale (NIHSS), the modified Barthel Index (mBI) and the modified Rankin Scale (mRS). This could indicate that ADM expression level is related to the severity of tissue damage. We suggest that increased ADM expression in PBL after acute ischemic stroke is most likely to indicate that these cells have been subjected to hypoxia and that the magnitude of expression is likely to be related to the volume of hypoxic tissue. Hypoxia can affect lymphocytes function and could affect the immune response to stroke. The correlation of ADM expression level with the measures of stroke severity implicates ADM – a potential blood bio-marker in studies of ischemic stroke.
- Published
- 2013
34. Diffusion-weighted magnetic resonance imaging detection of basal forebrain cholinergic degeneration in a mouse model
- Author
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Kerstin Pannek, Adam S. Hamlin, Georg M. Kerbler, Stephen E. Rose, Marianne D. Keller, Nyoman D. Kurniawan, and Elizabeth J. Coulson
- Subjects
Male ,Pathology ,medicine.medical_specialty ,Basal Forebrain ,Saporin ,Cognitive Neuroscience ,Hippocampus ,Mice ,Alzheimer Disease ,Fractional anisotropy ,Image Processing, Computer-Assisted ,medicine ,Animals ,Cholinergic neuron ,Basal forebrain ,biology ,Immunohistochemistry ,Cholinergic Neurons ,Mice, Inbred C57BL ,Disease Models, Animal ,Diffusion Magnetic Resonance Imaging ,Diffusion Tensor Imaging ,nervous system ,Neurology ,Nerve Degeneration ,biology.protein ,Cholinergic ,Neuroscience ,Diffusion MRI ,Tractography - Abstract
Loss of basal forebrain cholinergic neurons is an early and key feature of Alzheimer's disease, and magnetic resonance imaging (MRI) volumetric measurement of the basal forebrain has recently gained attention as a potential diagnostic tool for this condition. The aim of this study was to determine whether loss of basal forebrain cholinergic neurons underpins changes which can be detected through diffusion MRI using diffusion tensor imaging (DTI) and probabilistic tractography in a mouse model. To cause selective basal forebrain cholinergic degeneration, the toxin saporin conjugated to a p75 neurotrophin receptor antibody (mu-p75-SAP) was used. This resulted in ~25% loss of the basal forebrain cholinergic neurons and significant loss of terminal cholinergic projections in the hippocampus, as determined by histology. To test whether lesion of cholinergic neurons caused basal forebrain, hippocampal, or whole brain atrophy, we performed manual segmentation analysis, which revealed no significant atrophy in lesioned animals compared to controls (Rb-IgG-SAP). However, analysis by DTI of the basal forebrain area revealed a significant increase in fractional anisotropy (FA; +7.7%), mean diffusivity (MD; +6.1%), axial diffusivity (AD; +8.5%) and radial diffusivity (RD; +4.0%) in lesioned mice compared to control animals. These parameters strongly inversely correlated with the number of choline acetyl transferase-positive neurons, with FA showing the greatest association (r(2)=0.72), followed by MD (r(2)=0.64), AD (r(2)=0.64) and RD (r(2)=0.61). Moreover, probabilistic tractography analysis of the septo-hippocampal tracts originating from the basal forebrain revealed an increase in streamline MD (+5.1%) and RD (+4.3%) in lesioned mice. This study illustrates that moderate loss of basal forebrain cholinergic neurons (representing only a minor proportion of all septo-hippocampal axons) can be detected by measuring either DTI parameters of the basal forebrain nuclei or tractography parameters of the basal forebrain tracts. These findings provide increased support for using DTI and probabilistic tractography as non-invasive tools for diagnosing and/or monitoring the progression of conditions affecting the integrity of the basal forebrain cholinergic system in humans, including Alzheimer's disease.
- Published
- 2013
35. Correlation of MRI-Derived Apparent Diffusion Coefficients in Newly Diagnosed Gliomas with [18F]-Fluoro-L-Dopa PET: What Are We Really Measuring with Minimum ADC?
- Author
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Yaniv Gal, Paul Thomas, Stuart Crozier, Olivier Salvado, Michael Fay, Stephen E. Rose, Alan Coulthard, Pierrick Bourgeat, and Nicholas Dowson
- Subjects
Male ,Dopamine Agents ,Brain tumor ,Newly diagnosed ,Levodopa ,Correlation ,Fluorodeoxyglucose F18 ,Preoperative Care ,Tumor Grading ,Humans ,Medicine ,Effective diffusion coefficient ,Radiology, Nuclear Medicine and imaging ,In patient ,Radiation treatment planning ,Aged ,Aged, 80 and over ,Brain Neoplasms ,business.industry ,Brain ,Glioma ,Middle Aged ,medicine.disease ,body regions ,Diffusion Magnetic Resonance Imaging ,Positron-Emission Tomography ,Female ,Neurology (clinical) ,Radiopharmaceuticals ,business ,Nuclear medicine ,Glioblastoma - Abstract
BACKGROUND AND PURPOSE: There is significant interest in whether diffusion-weighted MR imaging indices, such as the minimum apparent diffusion coefficient, may be useful clinically for preoperative tumor grading and treatment planning. To help establish the pathologic correlate of minimum ADC, we undertook a study investigating the relationship between minimum ADC and maximum FDOPA PET uptake in patients with newly diagnosed glioblastoma multiforme. MATERIALS AND METHODS: MR imaging and FDOPA PET data were acquired preoperatively from 15 patients who were subsequently diagnosed with high-grade brain tumor (WHO grade III or IV) by histopathologic analysis. ADC and SUVR normalized FDOPA PET maps were registered to the corresponding CE MR imaging. Regions of minimum ADC within the FDOPA-defined tumor volume were anatomically correlated with areas of maximum FDOPA SUVR uptake. RESULTS: Minimal anatomic overlap was found between regions exhibiting minimum ADC (a putative marker of tumor cellularity) and maximum FDOPA SUVR uptake (a marker of tumor infiltration and proliferation). FDOPA SUVR measures for tumoral regions exhibiting minimum ADC (1.36 ± 0.22) were significantly reduced compared with those with maximum FDOPA uptake (2.45 ± 0.88, P = .0001). CONCLUSIONS: There was a poor correlation between minimum ADC and the most viable/aggressive component of high-grade gliomas. This study suggests that other factors, such as tissue compression and ischemia, may be contributing to restricted diffusion in GBM. Caution should be exercised in the clinical use of minimum ADC as a marker of tumor grade and the use of this index for guiding tumor biopsies preoperatively.
- Published
- 2012
36. Surface-Based fMRI-Driven Diffusion Tractography in the Presence of Significant Brain Pathology: A Study Linking Structure and Function in Cerebral Palsy
- Author
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Stephen E. Rose, Ross Cunnington, Roslyn N. Boyd, and Lee B. Reid
- Subjects
Male ,Central Nervous System ,Pathology ,Critical Care and Emergency Medicine ,Computer science ,lcsh:Medicine ,computer.software_genre ,Multimodal Imaging ,Nervous System ,Diagnostic Radiology ,Midbrain ,Machine Learning ,0302 clinical medicine ,Voxel ,Functional Magnetic Resonance Imaging ,Medicine and Health Sciences ,Diffusion Tractography ,Brain Damage ,Child ,lcsh:Science ,Trauma Medicine ,Brain Mapping ,Multidisciplinary ,medicine.diagnostic_test ,Radiology and Imaging ,05 social sciences ,Brain ,White Matter ,Magnetic Resonance Imaging ,Chemistry ,medicine.anatomical_structure ,Diffusion Tensor Imaging ,Neurology ,Physical Sciences ,Female ,medicine.symptom ,Anatomy ,Tractography ,Brainstem ,Alpha Hydroxy Acids ,Smoothing ,Research Article ,medicine.medical_specialty ,Adolescent ,Imaging Techniques ,Brain Morphometry ,Central nervous system ,Neuroimaging ,Brain damage ,Research and Analysis Methods ,050105 experimental psychology ,White matter ,03 medical and health sciences ,Diagnostic Medicine ,medicine ,Humans ,0501 psychology and cognitive sciences ,Multimodal imaging ,Cerebral Palsy ,lcsh:R ,Chemical Compounds ,Correction ,Biology and Life Sciences ,Magnetic resonance imaging ,Diffusion Magnetic Resonance Imaging ,lcsh:Q ,Functional magnetic resonance imaging ,computer ,Acids ,030217 neurology & neurosurgery ,Diffusion MRI ,Neuroscience - Abstract
Diffusion MRI (dMRI) tractography analyses are difficult to perform in the presence of brain pathology. Automated methods that rely on cortical parcellation for structural connectivity studies often fail, while manually defining regions is extremely time consuming and can introduce human error. Both methods also make assumptions about structure-function relationships that may not hold after cortical reorganisation. Seeding tractography with functional-MRI (fMRI) activation is an emerging method that reduces these confounds, but inherent smoothing of fMRI signal may result in the inclusion of irrelevant pathways. This paper describes a novel fMRI-seeded dMRI-analysis pipeline based on surface-meshes that reduces these issues and utilises machine-learning to generate task specific white matter pathways, minimising the requirement for manually-drawn ROIs. We directly compared this new strategy to a standard voxelwise fMRI-dMRI approach, by investigating correlations between clinical scores and dMRI metrics of thalamocortical and corticomotor tracts in 31 children with unilateral cerebral palsy. The surface-based approach successfully processed more participants (87%) than the voxel-based approach (65%), and provided significantly more-coherent tractography. Significant correlations between dMRI metrics and five clinical scores of function were found for the more superior regions of these tracts. These significant correlations were stronger and more frequently found with the surface-based method (15/20 investigated were significant; R2 = 0.43-0.73) than the voxelwise analysis (2 sig. correlations; 0.38 & 0.49). More restricted fMRI signal, better-constrained tractography, and the novel track-classification method all appeared to contribute toward these differences.
- Published
- 2016
37. Optimization of MRI-based scoring scales of brain injury severity in children with unilateral cerebral palsy
- Author
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Andrea Guzzetta, Yaniv Gal, Alex M. Pagnozzi, Stephen E. Rose, Nicholas Dowson, James D. Doecke, Roslyn N. Boyd, and Simona Fiori
- Subjects
Male ,medicine.medical_specialty ,Pathology ,Adolescent ,Periventricular white matter ,Sensitivity and Specificity ,Pediatrics ,Cerebral palsy ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,Magnetic resonance imaging ,030225 pediatrics ,Nuclear Medicine and Imaging ,Linear regression ,Image Interpretation, Computer-Assisted ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Brain injury ,Child ,Neuroradiology ,Observer Variation ,Trauma Severity Indices ,medicine.diagnostic_test ,business.industry ,Brain ,Reproducibility of Results ,Assisting Hand Assessment ,Structural assessment ,Radiology, Nuclear Medicine and Imaging ,Pediatrics, Perinatology and Child Health ,Perinatology and Child Health ,medicine.disease ,Region selection ,medicine.anatomical_structure ,Brain Injuries ,Child, Preschool ,Cohort ,Upper limb ,Female ,business ,Radiology ,030217 neurology & neurosurgery ,Algorithms - Abstract
Several scoring systems for measuring brain injury severity have been developed to standardize the classification of MRI results, which allows for the prediction of functional outcomes to help plan effective interventions for children with cerebral palsy. The aim of this study is to use statistical techniques to optimize the clinical utility of a recently proposed template-based scoring method by weighting individual anatomical scores of injury, while maintaining its simplicity by retaining only a subset of scored anatomical regions. Seventy-six children with unilateral cerebral palsy were evaluated in terms of upper limb motor function using the Assisting Hand Assessment measure and injuries visible on MRI using a semiquantitative approach. This cohort included 52 children with periventricular white matter injury and 24 with cortical and deep gray matter injuries. A subset of the template-derived cerebral regions was selected using a data-driven region selection algorithm. Linear regression was performed using this subset, with interaction effects excluded. Linear regression improved multiple correlations between MRI-based and Assisting Hand Assessment scores for both periventricular white matter (R squared increased to 0.45 from 0, P
- Published
- 2016
38. Structural hemispheric asymmetries in the human precentral gyrus hand representation
- Author
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R. Henderson, Pamela A. McCombe, Stephen E. Rose, Alan Coulthard, Fusun Baumann, T. Rowland, and Kerstin Pannek
- Subjects
Adult ,Male ,Functional Laterality ,Lateralization of brain function ,White matter ,Image Interpretation, Computer-Assisted ,Fractional anisotropy ,medicine ,Humans ,Diffusion Tractography ,Aged ,Brain Mapping ,General Neuroscience ,Motor Cortex ,Precentral gyrus ,Middle Aged ,Magnetic Resonance Imaging ,Diffusion Tensor Imaging ,medicine.anatomical_structure ,Laterality ,Anisotropy ,Female ,Psychology ,Neuroscience ,Psychomotor Performance ,Tractography ,Diffusion MRI - Abstract
The superior region of the precentral gyrus (preCG) is known to be actively involved with hand function and has been proposed as a possible neural correlate of handedness. To test this hypothesis, we used a combined voxel-based morphometric (VBM) asymmetry analysis of structural MRI, along with diffusion MRI (dMRI) tractography to investigate laterality indices of corticomotor white matter (WM) pathways, based on measures of fractional anisotropy (FA). The relationship between measures of motor performance and FA laterality indices was also investigated. In a cohort of 14 right-handed healthy participants, the VBM asymmetry analysis revealed an area within the preCG associated with hand representation. The tractography analysis revealed that this region possessed a number of major WM intrahemispheric connections to the brain stem, thalamus, cerebellum, postcentral, caudal middle and superior frontal, and superior and inferior parietal corticomotor regions. Within the corticospinal tracts, we found FA was significantly higher in the left hemisphere compared with the right. Furthermore, significant correlations were found between FA asymmetry measures projecting from this region, namely corticospinal tracts and those connecting the postcentral gyri, with grip strength and finger-tapping performance, respectively. A number of the motor pathways projecting from this region also exhibited leftward asymmetry of FA distributions. The findings from this study highlight the role of the left motor cortex in skilled motor performance and provide a framework for the study of the relationship between handedness and preCG hand representation in larger normative populations.
- Published
- 2012
39. Direct evidence of intra- and interhemispheric corticomotor network degeneration in amyotrophic lateral sclerosis: An automated MRI structural connectivity study
- Author
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Robert D. Henderson, Kerstin Pannek, Christopher Bell, Pamela A. McCombe, Nicole Hutchinson, Alan Coulthard, Stephen E. Rose, and Fusun Baumann
- Subjects
Adult ,Male ,Cognitive Neuroscience ,Corpus callosum ,computer.software_genre ,Efferent Pathways ,Functional Laterality ,White matter ,Neuroimaging ,Gyrus ,Voxel ,Fractional anisotropy ,Image Processing, Computer-Assisted ,medicine ,Humans ,Middle frontal gyrus ,Aged ,Models, Statistical ,Amyotrophic Lateral Sclerosis ,Reproducibility of Results ,Middle Aged ,Magnetic Resonance Imaging ,Diffusion Tensor Imaging ,medicine.anatomical_structure ,Neurology ,Head Movements ,Nerve Degeneration ,Female ,Nerve Net ,Artifacts ,Psychology ,Neuroscience ,computer ,Diffusion MRI - Abstract
Although the pathogenesis of amyotrophic lateral sclerosis (ALS) is uncertain, there is mounting neuroimaging evidence to suggest a mechanism involving the degeneration of multiple white matter (WM) motor and extramotor neural networks. This insight has been achieved, in part, by using MRI Diffusion Tensor Imaging (DTI) and the voxelwise analysis of anisotropy indices, along with DTI tractography to determine which specific motor pathways are involved with ALS pathology. Automated MRI structural connectivity analyses, which probe WM connections linking various functionally discrete cortical regions, have the potential to provide novel information about degenerative processes within multiple white matter (WM) pathways. Our hypothesis is that measures of altered intra- and interhemispheric structural connectivity of the primary motor and somatosensory cortex will provide an improved assessment of corticomotor involvement in ALS. To test this hypothesis, we acquired High Angular Resolution Diffusion Imaging (HARDI) scans along with high resolution structural images (sMRI) on 15 patients with clinical evidence of upper and lower motor neuron involvement, and 20 matched control participants. Whole brain probabilistic tractography was applied to define specific WM pathways connecting discrete corticomotor targets generated from anatomical parcellation of sMRI of the brain. The integrity of these connections was interrogated by comparing the mean fractional anisotropy (FA) derived for each WM pathway. To assist in the interpretation of results, we measured the reproducibility of the FA summary measures over time (6 months) in control participants. We also incorporated into our analysis pipeline the evaluation and replacement of outlier voxels due to head motion and physiological noise. When assessing corticomotor connectivity, we found a significant reduction in mean FA within a number of intra- and interhemispheric motor pathways in ALS patients. The abnormal intrahemispheric pathways include the corticospinal tracts involving the left and right precentral gyri (lh.preCG, rh.preCG) and brainstem (bs); right postcentral gyrus (rh.postCG) and bs; lh.preCG and left posterior cingulate gyrus (lh.PCG); rh.preCG and right posterior cingulate gyrus (rh.PCG); and the rh.preCG and right paracentral gyrus (rh.paraCG). The abnormal interhemispheric pathways included the lh.preCG and rh.preCG; lh.preCG and rh.paraCG; lh.preCG and right superior frontal gyrus (rh.supFG); lh.preCG and rh.postCG; rh.preCG and left paracentral gyrus (lh.paraCG); rh.preCG and left superior frontal gyrus (lh.supFG); and the rh.preCG and left caudal middle frontal gyrus (lh.caudMF). The reproducibility of the measurement of these pathways was high (variation less than 5%). Maps of the outlier rejection voxels, revealed clusters within the corpus callosum and corticospinal projections. This finding highlights the importance of correcting for motion artefacts and physiological noise when studying clinical populations. Our novel findings, many of which are consistent with known pathology, show extensive involvement and degeneration of multiple corticomotor pathways in patients with upper and lower motor neuron signs and provide support for the use of automated structural connectivity techniques for studying neurodegenerative disease processes.
- Published
- 2012
40. MRI Structural Connectivity, Disruption of Primary Sensorimotor Pathways, and Hand Function in Cerebral Palsy
- Author
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Kerstin Pannek, Stephen E. Rose, Roslyn N. Boyd, and Andrea Guzzetta
- Subjects
Male ,Adolescent ,Pyramidal Tracts ,Sensory system ,methods ,Cerebral palsy ,Thalamus ,medicine ,Humans ,Child ,Hand function ,medicine.diagnostic_test ,Cerebral Palsy ,General Neuroscience ,Motor Cortex ,Precentral gyrus ,Motor control ,Magnetic resonance imaging ,Hand ,medicine.disease ,Magnetic Resonance Imaging ,diagnosis/physiopathology ,Paresis ,physiology ,Female ,Adolescent, Cerebral Palsy ,diagnosis/physiopathology, Child, Female, Hand ,physiology, Humans, Magnetic Resonance Imaging ,methods, Male, Motor Cortex ,physiology, Nerve Net ,physiology, Paresis ,diagnosis/physiopathology, Pyramidal Tracts ,physiology, Thalamus ,Nerve Net ,Primary motor cortex ,Psychology ,Neuroscience ,Tractography - Abstract
Brain injury and subsequent plasticity of sensory and corticospinal pathways play an integral role in determining paretic hand function in congenital hemiplegia. There is limited knowledge regarding the relationship between the disruption of sensorimotor thalamic pathways projecting into the primary motor cortex and motor control. This study sought to investigate the relationship between the structural connectivity of motor networks that anatomically link the brain stem with the precentral and postcentral gyri with paretic motor sensory function by using an automated analysis strategy. Magnetic resonance imaging structural connectivity was measured by using high-angular-resolution diffusion imaging, probabilistic tractography, and the anatomic parcellation of high-resolution structural images in 16 children with congenital unilateral periventricular white-matter damage. Connectivity of the corticospinal and corticothalamic pathways was determined by using an asymmetry index based on the number of streamlines contained within these projections and compared with measures of paretic hand function and bimanual coordination. For cortical development, the volume of the ipsilesional precentral gyrus was significantly reduced. For connectivity measures, the numbers of streamlines in corticospinal tracts and corticothalamic pathways within the ipsilesional hemisphere were decreased compared with the contralesional side. The sensorimotor thalamic projections were more significantly correlated with paretic hand functions than were the corticospinal tracts. These data support the concept that preservation of sensorimotor thalamic pathways that directly project into the primary motor cortex has more influence on motor function control of the paretic hand than does preservation of corticospinal tracts.
- Published
- 2011
41. Biomarkers of disease in a case of familial lower motor neuron ALS
- Author
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Robert D. Henderson, Anthony N. Pettitt, Nicole Hutchinson, Kerstin Pannek, Pamela A. McCombe, Fusun Baumann, Stephen E. Rose, and Garth A. Nicholson
- Subjects
Adult ,Male ,Pathology ,medicine.medical_specialty ,DNA Mutational Analysis ,SOD1 ,Neural Conduction ,Pyramidal Tracts ,Disease ,Lower motor neuron ,Superoxide Dismutase-1 ,medicine ,Humans ,Amyotrophic lateral sclerosis ,Motor Neurons ,Superoxide Dismutase ,Upper motor neuron ,business.industry ,Amyotrophic Lateral Sclerosis ,Disease progression ,Clinical course ,General Medicine ,Middle Aged ,medicine.disease ,medicine.anatomical_structure ,Neurology ,Mutation ,Disease Progression ,Biomarker (medicine) ,Female ,Neurology (clinical) ,business ,Biomarkers - Abstract
ALS is a fatal disease with variable clinical course. There is no single reliable marker of disease progression. Sufficient records were available to study the case history of four family members with the uncommon G93V SOD1 mutation. Distal lower motor neuron (LMN) involvement occurred in all family members with onset from 30 to 51 years of age, with progression over more than six years. Between 2002 and 2009, we used electrophysiology as a biomarker to study disease progression in one patient, assessing the number of motor units in three nerves from different limbs. The loss of motor units showed an exponential decline with different half-lives in different nerves. Diffusion tractography was compared with a control to assess upper motor neuron (UMN) involvement and showed asymmetric evidence of abnormalities of the corticospinal tracts, providing evidence of central involvement despite the absence of UMN signs.
- Published
- 2010
42. Distinguishing Recurrent Primary Brain Tumor from Radiation Injury: A Preliminary Study Using a Susceptibility-Weighted MR Imaging−Guided Apparent Diffusion Coefficient Analysis Strategy
- Author
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Kerstin Pannek, C. McHenery, R. Buckley, Alan Coulthard, A. Al Sayyari, and Stephen E. Rose
- Subjects
Adult ,Male ,Oligodendroglioma ,Brain tumor ,Pilot Projects ,Astrocytoma ,Recurrent Tumor ,Diagnosis, Differential ,Text mining ,Humans ,Medicine ,Effective diffusion coefficient ,Radiology, Nuclear Medicine and imaging ,Medical diagnosis ,Radiation Injuries ,Radiation injury ,Aged ,Aged, 80 and over ,Brain Neoplasms ,business.industry ,Brain ,Middle Aged ,medicine.disease ,Mr imaging ,Diffusion Magnetic Resonance Imaging ,Concomitant ,Disease Progression ,Female ,Neurology (clinical) ,Neoplasm Recurrence, Local ,Glioblastoma ,Nuclear medicine ,business ,Follow-Up Studies - Abstract
BACKGROUND AND PURPOSE: The accurate delineation of tumor recurrence presents a significant problem in neuro-oncology. Our aim was to improve the identification of brain tumor recurrence from chemoradiation injury by using CE-SWI, a technique that provides improved visualization of the heterogeneous patterns of brain tumor pathology, to guide the analysis of ADC measures within the peritumoral territory. MATERIALS AND METHODS: Seventeen patients who were being treated for high-grade glial neoplasms took part in the study. All patients presented with new enhancing lesions on follow-up CE-T1. Recurrence or chemoradiation injury was confirmed from either histologic analysis or extensive clinical follow-up. Regions of enhancement on registered CE-SWI and CE-T1 images were extracted in a semiautomated fashion and transferred to coregistered ADC maps. Significant differences in ADC measures defined within the enhancement volumes on serial MR images were analyzed by using a nonparametric Kolmogorov-Smirnov approach and correlated with clinical follow-up diagnoses. RESULTS: Analysis of the serial data revealed that patients with a diagnosis of tumor recurrence had significantly reduced ADC measures within the enhancement volume delineated on CE-SWI. In contrast, patients with SD had significantly elevated ADC within the CE-SWI enhancement volume. CONCLUSIONS: The findings of an increase in enhancement volume delineated on serial CE-SWI maps, along with a concomitant reduction in ADC within this volume for patients with recurrent tumor, provide support for such an approach to be used to assist in follow-up patient management strategies.
- Published
- 2010
43. Fluid Registration of Diffusion Tensor Images Using Information Theory
- Author
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Ming Chang Chiang, Rebecca A. Dutton, Katie L. McMahon, Stephen E. Rose, Alex D. Leow, Paul M. Thompson, Arthur W. Toga, G.I. de Zubicaray, Marina Barysheva, and Andrea D. Klunder
- Subjects
Male ,Kullback–Leibler divergence ,Anisotropic diffusion ,Information Theory ,Image registration ,Sensitivity and Specificity ,Article ,Pattern Recognition, Automated ,Imaging, Three-Dimensional ,Image Interpretation, Computer-Assisted ,Humans ,Computer vision ,Electrical and Electronic Engineering ,Diffusion (business) ,Divergence (statistics) ,Navier–Stokes equations ,Image resolution ,Aged ,Mathematics ,Radiological and Ultrasound Technology ,business.industry ,Mathematical analysis ,Brain ,Reproducibility of Results ,Image Enhancement ,Computer Science Applications ,Diffusion Magnetic Resonance Imaging ,Subtraction Technique ,Female ,Artificial intelligence ,business ,Algorithms ,Software ,Diffusion MRI - Abstract
We apply an information-theoretic cost metric, the symmetrized Kullback-Leibler (sKL) divergence, or J-divergence, to fluid registration of diffusion tensor images. The difference between diffusion tensors is quantified based on the sKL-divergence of their associated probability density functions (PDFs). Three-dimensional DTI data from 34 subjects were fluidly registered to an optimized target image. To allow large image deformations but preserve image topology, we regularized the flow with a large-deformation diffeomorphic mapping based on the kinematics of a Navier-Stokes fluid. A driving force was developed to minimize the J-divergence between the deforming source and target diffusion functions, while reorienting the flowing tensors to preserve fiber topography. In initial experiments, we showed that the sKL-divergence based on full diffusion PDFs is adaptable to higher-order diffusion models, such as high angular resolution diffusion imaging (HARDI). The sKL-divergence was sensitive to subtle differences between two diffusivity profiles, showing promise for nonlinear registration applications and multisubject statistical analysis of HARDI data.
- Published
- 2008
44. Quantitative EEG indices of sub-acute ischaemic stroke correlate with clinical outcomes
- Author
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Simon Finnigan, Stephen E. Rose, Jonathan B. Chalk, and Michael Walsh
- Subjects
Male ,medicine.medical_specialty ,Subarachnoid hemorrhage ,Statistics as Topic ,Electroencephalography ,Severity of Illness Index ,Brain Ischemia ,Brain ischemia ,Central nervous system disease ,Physiology (medical) ,Internal medicine ,Severity of illness ,medicine ,Humans ,cardiovascular diseases ,Stroke ,Aged ,Aged, 80 and over ,Brain Mapping ,medicine.diagnostic_test ,Cerebral infarction ,business.industry ,Middle Aged ,Prognosis ,Quantitative electroencephalography ,medicine.disease ,Magnetic Resonance Imaging ,Sensory Systems ,Surgery ,Alpha Rhythm ,Neurology ,Cardiology ,Female ,Neurology (clinical) ,business - Abstract
We investigated the ability of quantitative electroencephalography (QEEG) measures in sub-acute stroke to assist monitoring or prognostication of stroke evolution. QEEG indices and National Institutes of Health Stroke Scale (NIHSS) scores were compared.Ischaemic cortical stroke patients were studied. Resting, 62-channel EEG and NIHSS score were acquired at 49+/-3h post-symptom onset, and NIHSS administered at 30+/-2 days post-stroke. Mean power was calculated for delta (1-4 Hz), theta (4.1-8 Hz), alpha (8.1-12.5 Hz) and beta (12.6-30 Hz) frequency bands, using a 62-channel electrode array and a 19-channel subset.Thirteen patients (6 male, median age 66, range 54-86 years) were studied. Sub-acute delta:alpha power ratio (DAR; r=0.91, P0.001), relative alpha power (r=-0.82, P0.01), and NIHSS score (r=0.92, P0.001) each were significantly correlated with 30-day NIHSS score. The former two significant correlations were upheld in 19-channel EEG data. QEEG measures involving theta or beta power were not significantly correlated with NIHSS scores.QEEG measures such as DAR demonstrate potential to augment bedside assessment of cerebral pathophysiology and prognostication of stroke evolution. A standard, 19-channel array seems adequate for these purposes. Future studies in larger samples should investigate the potential effects on these measures of sleep state and possible causes of artefacts.QEEG measures from a standard number of electrodes, if available rapidly and robust to potential artefacts, may inform future management of stroke patients.
- Published
- 2007
45. Direct mapping of hippocampal surfaces with intrinsic shape context
- Author
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Stephen E. Rose, Arthur W. Toga, Yonggang Shi, Greig I. de Zubicaray, Paul M. Thompson, Zhuowen Tu, and Ivo D. Dinov
- Subjects
Male ,Cognitive Neuroscience ,media_common.quotation_subject ,Population ,Hippocampus ,Sensitivity and Specificity ,Asymmetry ,Article ,Pattern Recognition, Automated ,Imaging, Three-Dimensional ,Alzheimer Disease ,Artificial Intelligence ,Image Interpretation, Computer-Assisted ,Humans ,Computer vision ,Shape context ,Invariant (mathematics) ,education ,Aged ,media_common ,Mathematics ,education.field_of_study ,business.industry ,Cognitive neuroscience of visual object recognition ,Reproducibility of Results ,Spherical harmonics ,Image Enhancement ,Magnetic Resonance Imaging ,Computational anatomy ,Neurology ,Subtraction Technique ,Female ,Artificial intelligence ,business ,Algorithm ,Algorithms ,Shape analysis (digital geometry) - Abstract
We propose in this paper a new method for the mapping of hippocampal (HC) surfaces to establish correspondences between points on HC surfaces and enable localized HC shape analysis. A novel geometric feature, the intrinsic shape context, is defined to capture the global characteristics of the HC shapes. Based on this intrinsic feature, an automatic algorithm is developed to detect a set of landmark curves that are stable across population. The direct map between a source and target HC surface is then solved as the minimizer of a harmonic energy function defined on the source surface with landmark constraints. For numerical solutions, we compute the map with the approach of solving partial differential equations on implicit surfaces. The direct mapping method has the following properties: (1) it has the advantage of being automatic; (2) it is invariant to the pose of HC shapes. In our experiments, we apply the direct mapping method to study temporal changes of HC asymmetry in Alzheimer's disease (AD) using HC surfaces from 12 AD patients and 14 normal controls. Our results show that the AD group has a different trend in temporal changes of HC asymmetry than the group of normal controls. We also demonstrate the flexibility of the direct mapping method by applying it to construct spherical maps of HC surfaces. Spherical harmonics (SPHARM) analysis is then applied and it confirms our results on temporal changes of HC asymmetry in AD.
- Published
- 2007
46. Gray and white matter changes in Alzheimer's disease: A diffusion tensor imaging study
- Author
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Jonathan B. Chalk, Stephen E. Rose, and Andrew L. Janke
- Subjects
Male ,Pathology ,medicine.medical_specialty ,Internal capsule ,Partial volume ,Neuropsychological Tests ,computer.software_genre ,White matter ,Alzheimer Disease ,Voxel ,Fractional anisotropy ,Image Processing, Computer-Assisted ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Thalamocortical radiations ,Aged ,Aged, 80 and over ,business.industry ,Anatomy ,Diffusion Magnetic Resonance Imaging ,medicine.anatomical_structure ,nervous system ,Frontal lobe ,Case-Control Studies ,Anisotropy ,Female ,business ,computer ,Diffusion MRI - Abstract
Purpose To investigate microstructural changes in cortical and white matter pathways in patients with Alzheimer's disease using diffusion tensor imaging (DTI). Materials and Methods Measures of mean diffusivity (MD) and fractional anisotropy (FA) were compared in the brains of 13 Alzheimer's disease (AD) patients and a group of 13 aged-matched control participants employing an optimized DTI technique involving a fully automated, voxel-based morphometric (VBM) analysis. Results After rigorous control for anatomical variation and confounding partial volume effects, we found significantly elevated MD measures within the hippocampus, amygdala, and medial temporal, parietal, and frontal lobe gray matter regions in the AD participants. The largest number of pixels with increased MD was localized bilaterally, within the posterior cingulate gyrus. The FA was significantly reduced within the thalamus, parietal white matter, and posterior limbs of the internal capsule, indicating significant involvement of corticothalamic and thalamocortical radiations. Conclusion This study demonstrates that rigorous VBM analysis of DTI data can be used to investigate microstructural changes in cortical, subcortical, and white matter regions in AD. J. Magn. Reson. Imaging 2007. © 2007 Wiley-Liss, Inc.
- Published
- 2007
47. Structural connectivity of the anterior cingulate in children with unilateral cerebral palsy due to white matter lesions
- Author
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Kerstin Pannek, David Raffelt, Simona Fiori, Simon M Scheck, Roslyn N. Boyd, and Stephen E. Rose
- Subjects
Male ,ROI, region of interest ,Precuneus ,AFD, apparent fibre density ,SIFT, spherical deconvolution informed filtering of tractograms ,Audiology ,Severity of Illness Index ,lcsh:RC346-429 ,Functional Laterality ,Executive Function ,Leukoencephalopathies ,Image Processing, Computer-Assisted ,UCP, unilateral cerebral palsy ,FA, fractional anisotropy ,Child ,ACC, anterior cingulate cortex ,Regular Article ,medicine.anatomical_structure ,Diffusion Tensor Imaging ,Neurology ,Child, Preschool ,lcsh:R858-859.7 ,Female ,FOD, fibre orientation distribution ,Psychology ,psychological phenomena and processes ,medicine.medical_specialty ,Adolescent ,Cognitive Neuroscience ,lcsh:Computer applications to medicine. Medical informatics ,behavioral disciplines and activities ,Gyrus Cinguli ,CTD, children with typical development ,Neuropsychology ,Fractional anisotropy ,medicine ,Middle frontal gyrus ,Humans ,Radiology, Nuclear Medicine and imaging ,WM, white matter ,CP, cerebral palsy ,lcsh:Neurology. Diseases of the nervous system ,Anterior cingulate cortex ,MD, mean diffusivity ,Analysis of Variance ,HARDI, high angular resolution diffusion imaging ,Cerebral Palsy ,Frontal gyrus ,Hyperintensity ,Superior frontal gyrus ,nervous system ,Anisotropy ,Neurology (clinical) ,DTI, diffusion tensor imaging ,Nerve Net ,Neuroscience ,MRI, magnetic resonance imaging ,Executive dysfunction - Abstract
In this work we investigate the structural connectivity of the anterior cingulate cortex (ACC) and its link with impaired executive function in children with unilateral cerebral palsy (UCP) due to periventricular white matter lesions. Fifty two children with UCP and 17 children with typical development participated in the study, and underwent diffusion and structural MRI. Five brain regions were identified for their high connectivity with the ACC using diffusion MRI fibre tractography: the superior frontal gyrus, medial orbitofrontal cortex, rostral middle frontal gyrus, precuneus and isthmus cingulate. Structural connectivity was assessed in pathways connecting these regions to the ACC using three diffusion MRI derived measures: fractional anisotropy (FA), mean diffusivity (MD) and apparent fibre density (AFD), and compared between participant groups. Furthermore we investigated correlations of these measures with executive function as assessed by the Flanker task. The ACC–precuneus tract had significantly different MD (p, Highlights • Anterior cingulate connectivity is affected in children with PWM lesions. • This reduced connectivity correlates with impaired executive function. • AFD provides improved tract-specific analysis compared with DTI.
- Published
- 2015
48. Diffusion Tractography Biomarkers of Pediatric Cerebellar Hypoplasia/Atrophy: Preliminary Results Using Constrained Spherical Deconvolution
- Author
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R Del Punta, Andrea Guzzetta, Andrea Poretti, Stephen E. Rose, Roberta Battini, Giovanni Cioni, Rosa Pasquariello, Kerstin Pannek, Michela Tosetti, and Simona Fiori
- Subjects
Male ,Cerebellum ,Developmental Disabilities ,Pontocerebellar hypoplasia ,Pyramidal Tracts ,Nervous System Malformations ,Pediatrics ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Fractional anisotropy ,Image Interpretation, Computer-Assisted ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Child ,Cerebellar ataxia ,business.industry ,Anatomy ,medicine.disease ,White Matter ,medicine.anatomical_structure ,Diffusion Tensor Imaging ,nervous system ,Corticospinal tract ,Cerebellar atrophy ,Female ,Neurology (clinical) ,Cerebellar hypoplasia (non-human) ,medicine.symptom ,business ,030217 neurology & neurosurgery ,Biomarkers ,Tractography - Abstract
BACKGROUND AND PURPOSE: Advances in MR imaging modeling have improved the feasibility of reconstructing crossing fibers, with increasing benefits in delineating angulated tracts such as cerebellar tracts by using tractography. We hypothesized that constrained spherical deconvolution–based probabilistic tractography could successfully reconstruct cerebellar tracts in children with cerebellar hypoplasia/atrophy and that diffusion scalars of the reconstructed tracts could differentiate pontocerebellar hypoplasia, nonprogressive cerebellar hypoplasia, and progressive cerebellar atrophy. MATERIALS AND METHODS: Fifteen children with cerebellar ataxia and pontocerebellar hypoplasia, nonprogressive cerebellar hypoplasia or progressive cerebellar atrophy and 7 controls were included in this study. Cerebellar and corticospinal tracts were reconstructed by using constrained spherical deconvolution. Scalar measures (fractional anisotropy and mean, axial and radial diffusivity) were calculated. A general linear model was used to determine differences among groups for diffusion MR imaging scalar measures, and post hoc pair-wise comparisons were performed. RESULTS: Cerebellar and corticospinal tracts were successfully reconstructed in all subjects. Significant differences in diffusion MR imaging scalars were found among groups, with fractional anisotropy explaining the highest variability. All groups with cerebellar pathologies showed lower fractional anisotropy compared with controls, with the exception of cerebellar hypoplasia. CONCLUSIONS: This study shows the feasibility of constrained spherical deconvolution to reconstruct cerebellar and corticospinal tracts in children with morphologic cerebellar pathologies. In addition, the preliminary results show the potential utility of quantitative analysis of scalars of the cerebellar white matter tracts in children with cerebellar pathologies such as cerebellar hypoplasia and atrophy. Further studies with larger cohorts of patients are needed to validate the clinical significance of our preliminary results. AD : axial diffusivity CA : progressive cerebellar atrophy CH : nonprogressive cerebellar hypoplasia CPCT : corticopontocerebellar tract CST : corticospinal tract CTT : cerebellar-thalamic tract dMRI : diffusion MR imaging FA : fractional anisotropy MD : mean diffusivity PCH : pontocerebellar hypoplasia RD : radial diffusivity
- Published
- 2015
49. Motor pathway degeneration in young ataxia telangiectasia patients: A diffusion tractography study
- Author
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Stephen E. Rose, Kate Sinclair, James D. Doecke, Ishani Sahama, Simona Fiori, Lee B. Reid, Kerstin Pannek, and Martin F. Lavin
- Subjects
Adult ,Male ,congenital, hereditary, and neonatal diseases and abnormalities ,Cerebellum ,Pathology ,medicine.medical_specialty ,Adolescent ,Diffusion magnetic resonance imaging ,Cognitive Neuroscience ,Brain Structure and Function ,Degeneration (medical) ,Gene mutation ,lcsh:Computer applications to medicine. Medical informatics ,Efferent Pathways ,lcsh:RC346-429 ,White matter ,Ataxia Telangiectasia ,Young Adult ,Whole tract statistics ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Diffusion Tractography ,Child ,lcsh:Neurology. Diseases of the nervous system ,Brain ,Regular Article ,medicine.disease ,White Matter ,medicine.anatomical_structure ,Diffusion Tensor Imaging ,Neurology ,Ataxia-telangiectasia ,lcsh:R858-859.7 ,Female ,Neurology (clinical) ,Psychology ,Neuroscience ,Diffusion MRI - Abstract
Background Our understanding of the effect of ataxia–telangiectasia mutated gene mutations on brain structure and function is limited. In this study, white matter motor pathway integrity was investigated in ataxia telangiectasia patients using diffusion MRI and probabilistic tractography. Methods Diffusion MRI were obtained from 12 patients (age range: 7–22 years, mean: 12 years) and 12 typically developing age matched participants (age range 8–23 years, mean: 13 years). White matter fiber tracking and whole tract statistical analyses were used to assess quantitative fractional anisotropy and mean diffusivity differences along the cortico-ponto-cerebellar, cerebellar-thalamo-cortical, somatosensory and lateral corticospinal tract length in patients using a linear mixed effects model. White matter tract streamline number and apparent fiber density in patient and control tracts were also assessed. Results Reduced fractional anisotropy along all analyzed patient tracts were observed (p, Highlights • Corticomotor and corticospinal ataxia telangiectasia patient tracts were analyzed. • Decreases in fractional anisotropy occurred along patient tracts. • Mean diffusivity was reduced in cerebellar peduncles in patients. • Patient corticospinal streamline number and apparent fiber density were reduced. • Young ataxia telangiectasia patients show advanced white matter degeneration.
- Published
- 2015
50. Statistical machine learning to identify traumatic brain injury (TBI) from structural disconnections of white matter networks
- Author
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Olivier Salvado, Jurgen Fripp, Kerstin Pannek, Jhimli Mitra, Pierrick Bourgeat, Stephen E. Rose, Jane L. Mathias, Soumya Ghose, Kaikai Shen, and D. Jamie Taylor
- Subjects
Adult ,Male ,Traumatic brain injury ,Cognitive Neuroscience ,Poison control ,Diffuse Axonal Injury ,Machine learning ,computer.software_genre ,030218 nuclear medicine & medical imaging ,White matter ,Machine Learning ,03 medical and health sciences ,0302 clinical medicine ,Neuroimaging ,Fractional anisotropy ,Brain Injuries, Traumatic ,Image Interpretation, Computer-Assisted ,Neural Pathways ,medicine ,Connectome ,Humans ,business.industry ,Diffuse axonal injury ,Middle Aged ,medicine.disease ,White Matter ,medicine.anatomical_structure ,Diffusion Tensor Imaging ,Neurology ,Female ,Artificial intelligence ,Psychology ,business ,Neuroscience ,computer ,030217 neurology & neurosurgery ,Diffusion MRI - Abstract
Identifying diffuse axonal injury (DAI) in patients with traumatic brain injury (TBI) presenting with normal appearing radiological MRI presents a significant challenge. Neuroimaging methods such as diffusion MRI and probabilistic tractography, which probe the connectivity of neural networks, show significant promise. We present a machine learning approach to classify TBI participants primarily with mild traumatic brain injury (mTBI) based on altered structural connectivity patterns derived through the network based statistical analysis of structural connectomes generated from TBI and age-matched control groups. In this approach, higher order diffusion models were used to map white matter connections between 116 cortical and subcortical regions. Tracts between these regions were generated using probabilistic tracking and mean fractional anisotropy (FA) measures along these connections were encoded in the connectivity matrices. Network-based statistical analysis of the connectivity matrices was performed to identify the network differences between a representative subset of the two groups. The affected network connections provided the feature vectors for principal component analysis and subsequent classification by random forest. The validity of the approach was tested using data acquired from a total of 179 TBI patients and 146 controls participants. The analysis revealed altered connectivity within a number of intra- and inter-hemispheric white matter pathways associated with DAI, in consensus with existing literature. A mean classification accuracy of 68.16%±1.81% and mean sensitivity of 80.0%±2.36% were achieved in correctly classifying the TBI patients evaluated on the subset of the participants that was not used for the statistical analysis, in a 10-fold cross-validation framework. These results highlight the potential for statistical machine learning approaches applied to structural connectomes to identify patients with diffusive axonal injury.
- Published
- 2015
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