13 results on '"Leach, James A."'
Search Results
2. Spectrum of cerebral arterial and venous abnormalities in Alagille syndrome
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Carpenter, Candice D., Linscott, Luke L., Leach, James L., Vadivelu, Sudhakar, and Abruzzo, Todd
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- 2018
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3. Clinical validation of synthetic brain MRI in children: initial experience
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West, Hollie, Leach, James L., Jones, Blaise V., Care, Marguerite, Radhakrishnan, Rupa, Merrow, Arnold C., Alvarado, Enrique, and Serai, Suraj D.
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- 2017
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4. Prospective detection of cortical dysplasia on clinical MRI in pediatric intractable epilepsy
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Radhakrishnan, Rupa, Leach, James L., Mangano, Francesco T., Gelfand, Michael J., Rozhkov, Leonid, Miles, Lili, and Greiner, Hansel M.
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- 2016
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5. Developmental venous anomalies of the brain in children — imaging spectrum and update
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Linscott, Luke L., Leach, James L., Jones, Blaise V., and Abruzzo, Todd A.
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- 2016
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6. Reading in children with drug-resistant epilepsy was related to functional connectivity in cognitive control regions.
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Kraus, Dror, Vannest, Jennifer, Arya, Ravindra, Hutton, John S., Leach, James L., Mangano, Francesco T., Tenney, Jeffrey R., Byars, Anna W., DeWitt, Thomas G., Horowitz‐Kraus, Tzipi, and Horowitz-Kraus, Tzipi
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FUNCTIONAL connectivity ,CHILDHOOD epilepsy ,FUNCTIONAL magnetic resonance imaging ,AGRAMMATISM ,PARTIAL epilepsy ,CINGULATE cortex ,BRAIN ,COGNITION ,BRAIN mapping ,MAGNETIC resonance imaging ,DRUGS ,READING - Abstract
Aim: This study aimed to define whether individuals with drug-resistant focal epilepsy also used regions related to cognitive control to facilitate reading.Methods: We focused on patients with drug-resistant focal epilepsy in 2011-2014, who were aged 8-20 years and were being treated at the Cincinnati Children's Hospital, USA. They performed a verb generation functional magnetic resonance imaging task known to involve language and cognitive control, as well as a formal reading assessment. The reading scores were correlated with functional connectivity of the anterior cingulate cortex (ACC) using seed-to-voxel analysis.Results: There were 81 potential patients and 13 (seven females) met the inclusion criteria. Their age at seizure onset was 0-13 years, and they had a mean age of 12.66 ± 3.17 years at the time of the study. Individuals with epilepsy demonstrated average intelligence and word reading ability. Their reading scores were positively correlated with functional connectivity between the ACC and regions related to emotional processing (right amygdala), learning and language processing (left cerebellum) and visual processing.Conclusion: Our results support the role that the ACC plays in proficient reading among children with drug-resistant epilepsy, even in those with epileptogenic foci in areas related to language. [ABSTRACT FROM AUTHOR]- Published
- 2020
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7. Neonatal Functional and Structural Connectivity Are Associated with Cerebral Palsy at Two Years of Age.
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Merhar, Stephanie L., Gozdas, Elveda, Tkach, Jean A., Parikh, Nehal A., Kline-Fath, Beth M., He, Lili, Yuan, Weihong, Altaye, Mekibib, Leach, James L., and Holland, Scott K.
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BIOMARKERS ,BRAIN ,BRAIN injuries ,BRAIN mapping ,CEREBRAL palsy ,MAGNETIC resonance imaging ,PSYCHOLOGY of movement ,RISK assessment ,NEURAL pathways ,CEREBRAL anoxia-ischemia ,WHITE matter (Nerve tissue) ,DISEASE complications ,DISEASE risk factors ,CHILDREN - Abstract
Objective The accuracy of structural magnetic resonance imaging (MRI) to predict later cerebral palsy (CP) in newborns with perinatal brain injury is variable. Diffusion tensor imaging (DTI) and task-based functional MRI (fMRI) show promise as predictive tools. We hypothesized that infants who later developed CP would have reduced structural and functional connectivity as compared with those without CP. Study Design We performed DTI and fMRI using a passive motor task at 40 to 48 weeks' postmenstrual age in 12 infants with perinatal brain injury. CP was diagnosed at age 2 using a standardized examination. Results Five infants had CP at 2 years of age, and seven did not have CP. Tract-based spatial statistics showed a widespread reduction of fractional anisotropy (FA) in almost all white matter tracts in the CP group. Using the median FA value in the corticospinal tracts as a cutoff, FA was 100% sensitive and 86% specific to predict CP compared with a sensitivity of 60 to 80% and a specificity of 71% for structural MRI. During fMRI, the CP group had reduced functional connectivity from the right supplemental motor area as compared with the non-CP group. Conclusion DTI and fMRI obtained soon after birth are potential biomarkers to predict CP in newborns with perinatal brain injury. [ABSTRACT FROM AUTHOR]
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- 2020
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8. Multidimensional morphometric 3D MRI analyses for detecting brain abnormalities in children: Impact of control population
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Wilke, Marko, Rose, Douglas F., Holland, Scott K., and Leach, James L.
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Male ,Adolescent ,Age Factors ,Brain ,Magnetic Resonance Imaging ,Statistics, Nonparametric ,Young Adult ,Age Distribution ,Imaging, Three-Dimensional ,Brain Injuries ,Child, Preschool ,Humans ,Female ,Sex Distribution ,Child ,Research Articles ,Algorithms - Abstract
Automated morphometric approaches are used to detect epileptogenic structural abnormalities in 3D MR images in adults, using the variance of a control population to obtain z‐score maps in an individual patient. Due to the substantial changes the developing human brain undergoes, performing such analyses in children is challenging. This study investigated six features derived from high‐resolution T1 datasets in four groups: normal children (1.5T or 3T data), normal clinical scans (3T data), and patients with structural brain lesions (3T data), with each n = 10. Normative control data were obtained from the NIH study on normal brain development (n = 401). We show that control group size substantially influences the captured variance, directly impacting the patient's z‐scores. Interestingly, matching on gender does not seem to be beneficial, which was unexpected. Using data obtained at higher field scanners produces slightly different base rates of suprathreshold voxels, as does using clinically derived normal studies, suggesting a subtle but systematic effect of both factors. Two approaches for controlling suprathreshold voxels in a multidimensional approach (combining features and requiring a minimum cluster size) were shown to be substantial and effective in reducing this number. Finally, specific strengths and limitations of such an approach could be demonstrated in individual cases. Hum Brain Mapp 35:3199–3215, 2014. © 2013 Wiley Periodicals, Inc.
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- 2013
9. Brain imaging with synthetic MR in children: clinical quality assessment.
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Betts, Aaron, Leach, James, Jones, Blaise, Zhang, Bin, and Serai, Suraj
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BRAIN , *RADIOGRAPHY , *EVALUATION of diagnostic imaging , *AGE distribution , *COMPUTER software , *MAGNETIC resonance imaging , *PEDIATRICS , *QUALITY assurance - Abstract
Introduction: Synthetic magnetic resonance imaging is a quantitative imaging technique that measures inherent T1-relaxation, T2-relaxation, and proton density. These inherent tissue properties allow synthesis of various imaging sequences from a single acquisition. Clinical use of synthetic MR imaging has been described in adult populations. However, use of synthetic MR imaging has not been previously reported in children. The purpose of this study is to report our assessment of diagnostic image quality using synthetic MR imaging in children. Methods: Synthetic MR acquisition was obtained in a sample of children undergoing brain MR imaging. Image quality assessments were performed on conventional and synthetic T1-weighted, T2-weighted, and FLAIR images. Standardized linear measurements were performed on conventional and synthetic T2 images. Estimates of patient age based upon myelination patterns were also performed. Results: Conventional and synthetic MR images were evaluated on 30 children. Using a 4-point assessment scale, conventional imaging performed better than synthetic imaging for T1-weighted, T2-weighted, and FLAIR images. When the assessment was simplified to a dichotomized scale, the conventional and synthetic T1-weighted and T2-weighted images performed similarly. However, the superiority of conventional FLAIR images persisted in the dichotomized assessment. There were no statistically significant differences between linear measurements made on T2-weighted images. Estimates of patient age based upon pattern of myelination were also similar between conventional and synthetic techniques. Conclusion: Synthetic MR imaging may be acceptable for clinical use in children. However, users should be aware of current limitations that could impact clinical utility in the software version used in this study. [ABSTRACT FROM AUTHOR]
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- 2016
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10. Diffusion tensor imaging detects white matter abnormalities and associated cognitive deficits in chronic adolescent TBI.
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Adamson, Chris, Yuan, Weihong, Babcock, Lynn, Leach, James L., Seal, Marc L., Holland, Scott K., and Wade, Shari L.
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RADIOGRAPHY ,COMPLICATIONS of brain injuries ,NEURAL physiology ,BIOMARKERS ,BRAIN ,BRAIN injuries ,CHRONIC diseases ,COGNITION disorders ,COGNITION in adolescence ,COMPARATIVE studies ,MAGNETIC resonance imaging ,NEUROPSYCHOLOGICAL tests ,NEURORADIOLOGY ,NONPARAMETRIC statistics ,QUESTIONNAIRES ,SCALES (Weighing instruments) ,TOMOGRAPHY ,MULTIPLE regression analysis ,SEVERITY of illness index ,CASE-control method ,DESCRIPTIVE statistics ,GLASGOW Coma Scale ,TRAUMA severity indices ,ADOLESCENCE - Abstract
Primary objective: This study examined long-term alterations in white matter microstructure following TBI in adolescence using diffusion tensor imaging (DTI). It was hypothesized that white matter integrity would be compromised in adolescents with TBI and would correlate with measures of executive functioning and cognitive abilities. Research design: This study employed whole-brain, voxel-wise, statistical comparison of DTI indices in youth of 12-17 years old (mean = 15.06) with TBI vs an age- and gender-matched cohort (mean age = 15.37). Methods and procedures: This study scanned 17 adolescents with complicated-mild-to-severe TBI, 1-3 years after injury, and 13 healthy adolescents. Tract-Based Spatial Statistics (TBSS) was employed for DTI analysis. Main outcomes and results: Overall diffusivity elevations were found in the TBI group with increases in axial diffusivity in the right hemisphere. White matter integrity was associated with word reading, planning and processing times in the TBI group, but not healthy controls. Conclusions: The detected abnormalities in axial diffusivity may reflect neuronal regeneration and cerebral reorganization after injury. These findings provide tentative evidence of persistent white matter alteration following TBI in adolescence. Associations of DTI indices with cognitive performance following TBI provide tentative support for links between white matter integrity and performance post-TBI. [ABSTRACT FROM AUTHOR]
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- 2013
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11. White Matter Alteration Following SWAT Explosive Breaching Training and the Moderating Effect of a Neck Collar Device: A DTI and NODDI Study.
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Yuan, Weihong, Dudley, Jonathan, Slutsky-Ganesh, Alexis B, Leach, James, Scheifele, Pete, Altaye, Mekibib, Foss, Kim D Barber, Diekfuss, Jed D, Rhea, Christopher K, Myer, Gregory D, and Barber Foss, Kim D
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BRAIN , *RESEARCH , *NEURONS , *RESEARCH methodology , *MAGNETIC resonance imaging , *MEDICAL cooperation , *EVALUATION research , *COMPARATIVE studies , *RESEARCH funding , *ANALYTICAL chemistry - Abstract
Introduction: Special Weapons and Tactics (SWAT) personnel who practice breaching with blast exposure are at risk for blast-related head trauma. We aimed to investigate the impact of low-level blast exposure on underlying white matter (WM) microstructure based on diffusion tensor imaging (DTI) and neurite orientation and density imaging (NODDI) in SWAT personnel before and after breacher training. Diffusion tensor imaging is an advanced MRI technique sensitive to underlying WM alterations. NODDI is a novel MRI technique emerged recently that acquires diffusion weighted data from multiple shells modeling for different compartments in the microstructural environment in the brain. We also aimed to evaluate the effect of a jugular vein compression collar device in mitigating the alteration of the diffusion properties in the WM as well as its role as a moderator on the association between the diffusion property changes and the blast exposure.Materials and Methods: Twenty-one SWAT personnel (10 non-collar and 11 collar) completed the breacher training and underwent MRI at both baseline and after blast exposure. Diffusion weighted data were acquired with two shells (b = 1,000, 2,000 s/mm2) on 3T Phillips scanners. Diffusion tensor imaging metrices, including fractional anisotropy, mean, axial, and radial diffusivity, and NODDI metrics, including neurite density index (NDI), isotropic volume fraction (fiso), and orientation dispersion index, were calculated. Tract-based spatial statistics was used in the voxel-wise statistical analysis. Post hoc analyses were performed for the quantification of the pre- to post-blast exposure diffusion percentage change in the WM regions with significant group difference and for the assessment of the interaction of the relationship between blast exposure and diffusion alteration.Results: The non-collar group exhibited significant pre- to post-blast increase in NDI (corrected P < .05) in the WM involving the right internal capsule, the right posterior corona radiation, the right posterior thalamic radiation, and the right sagittal stratum. A subset of these regions showed significantly greater alteration in NDI and fiso in the non-collar group when compared with those in the collar group (corrected P < .05). In addition, collar wearing exhibited a significant moderating effect for the alteration of fiso for its association with average peak pulse pressure.Conclusions: Our data provided initial evidence of the impact of blast exposure on WM diffusion alteration based on both DTI and NODDI. The mitigating effect of WM diffusivity changes and the moderating effect of collar wearing suggest that the device may serve as a promising solution to protect WM against blast exposure. [ABSTRACT FROM AUTHOR]- Published
- 2021
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12. Mild Jugular Compression Collar Ameliorated Changes in Brain Activation of Working Memory after One Soccer Season in Female High School Athletes.
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Yuan, Weihong, Dudley, Jonathan, Barber Foss, Kim D., Ellis, Jonathan D., Thomas, Staci, Galloway, Ryan T., DiCesare, Christopher A., Leach, James L., Adams, Janet, Maloney, Thomas, Gadd, Brooke, Smith, David, Epstein, Jeff N., Grooms, Dustin R., Logan, Kelsey, Howell, David R., Altaye, Mekibib, and Myer, Gregory D.
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BRAIN concussion , *MAGNETIC resonance imaging , *BRAIN imaging , *RADIOGRAPHY , *BRAIN , *SPORTS injuries - Abstract
Recent neuroimaging studies have suggested that repetitive subconcussive head impacts, even after only one sport season, may lead to pre- to post-season structural and functional alterations in male high school football athletes. However, data on female athletes are limited. In the current investigation, we aimed to (1) assess the longitudinal pre- to post-season changes in functional MRI (fMRI) of working memory and working memory performance, (2) quantify the association between the pre- to post-season change in fMRI of working memory and the exposure to head impact and working memory performance, and (3) assess whether wearing a neck collar designed to reduce intracranial slosh via mild compression of the jugular veins can ameliorate the changes in fMRI brain activation observed in the female high school athletes who did not wear collars after a full soccer season. A total of 48 female high school soccer athletes (age range: 14.00–17.97 years) were included in the study. These athletes were assigned to the non-collar group (
n = 21) or to the collar group (n = 27). All athletes undewent MRI at both pre-season and post-season. In each session, a fMRI verbal N-Back task was used to engage working memory. A significant pre- to post-season increase in fMRI blood oxygen level dependent (BOLD) signal was demonstrated when performing the N-back working memory task in the non-collar group but not in the collar group, despite the comparable exposure to head impacts during the season between the two groups. The collar group demonstrated significantly smaller pre- to post-season change in fMRI BOLD signal than the non-collar group, suggesting a potential protective effect from the collar device. Significant correlations were also found between the pre- to post-season increase in fMRI brain activation and the decrease in task accuracy in the non-collar group, indicating an association between the compensatory mechanism in underlying neurophysiology and the alteration in the behavioral outcomes. [ABSTRACT FROM AUTHOR]- Published
- 2018
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13. Vagus Nerve Stimulation for Electrographic Status Epilepticus in Slow-Wave Sleep.
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Carosella, Christopher M., Greiner, Hansel M., Byars, Anna W., Arthur, Todd M., Leach, James L., Turner, Michele, Holland, Katherine D., Mangano, Francesco T., and Arya, Ravindra
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VAGUS nerve , *ELECTRONOGRAPHY , *DECISION making , *NEURAL stimulation , *EPILEPSY surgery , *STATUS epilepticus treatment , *BRAIN , *ELECTROENCEPHALOGRAPHY , *SLEEP , *STATUS epilepticus - Abstract
Background: Electrographic status epilepticus in slow sleep or continuous spike and waves during slow-wave sleep is an epileptic encephalopathy characterized by seizures, neurocognitive regression, and significant activation of epileptiform discharges during nonrapid eye movement sleep. There is no consensus on the diagnostic criteria and evidence-based optimal treatment algorithm for children with electrographic status epilepticus in slow sleep.Patient Description: We describe a 12-year-old girl with drug-resistant electrographic status epilepticus in slow wave sleep that was successfully treated with vagus nerve stimulation. Her clinical presentation, presurgical evaluation, decision-making, and course after vagus nerve stimulator implantation are described in detail.Findings: After vagus nerve stimulator implantation, the girl remained seizure free for more than a year, resolved the electrographic status epilepticus in slow sleep pattern on electroencephalography, and exhibited significant cognitive improvement.Conclusion: Vagus nerve stimulation may be considered for electrographic status epilepticus in slow sleep. [ABSTRACT FROM AUTHOR]- Published
- 2016
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