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Background: Magnetic Resonance Spin TomogrAphy in Time-domain (MR-STAT) can reconstruct whole-brain multi-parametric quantitative maps (eg, T 1 , T 2 ) from a 5-minute MR acquisition. These quantitative maps can be leveraged for synthetization of clinical image contrasts., Purpose: The objective was to assess image quality and overall diagnostic accuracy of synthetic MR-STAT contrasts compared to conventional contrast-weighted images., Study Type: Prospective cross-sectional clinical trial., Population: Fifty participants with a median age of 45 years (range: 21-79 years) consisting of 10 healthy participants and 40 patients with neurological diseases (brain tumor, epilepsy, multiple sclerosis or stroke)., Field Strength/sequence: 3T/Conventional contrast-weighted imaging (T 1 /T 2 weighted, proton density [PD] weighted, and fluid-attenuated inversion recovery [FLAIR]) and a MR-STAT acquisition (2D Cartesian spoiled gradient echo with varying flip angle preceded by a non-selective inversion pulse)., Assessment: Quantitative T 1 , T 2 , and PD maps were computed from the MR-STAT acquisition, from which synthetic contrasts were generated. Three neuroradiologists blinded for image type and disease randomly and independently evaluated synthetic and conventional datasets for image quality and diagnostic accuracy, which was assessed by comparison with the clinically confirmed diagnosis., Statistical Tests: Image quality and consequent acceptability for diagnostic use was assessed with a McNemar's test (one-sided α = 0.025). Wilcoxon signed rank test with a one-sided α = 0.025 and a margin of Δ = 0.5 on the 5-level Likert scale was used to assess non-inferiority., Results: All data sets were similar in acceptability for diagnostic use (≥3 Likert-scale) between techniques (T 1 w:P = 0.105, PDw:P = 1.000, FLAIR:P = 0.564). However, only the synthetic MR-STAT T 2 weighted images were significantly non-inferior to their conventional counterpart; all other synthetic datasets were inferior (T 1 w:P = 0.260, PDw:P = 1.000, FLAIR:P = 1.000). Moreover, true positive/negative rates were similar between techniques (conventional: 88%, MR-STAT: 84%)., Data Conclusion: MR-STAT is a quantitative technique that may provide radiologists with clinically useful synthetic contrast images within substantially reduced scan time., Evidence Level: 1 Technical Efficacy: Stage 2., (© 2022 The Authors. Journal of Magnetic Resonance Imaging published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.)

Introduction: The term "frontotemporal lobar degeneration" (FTLD) includes a large set of neurodegenerative diseases, which are heterogeneous in their genetic, pathologic and clinical aspects. This review will focus on the most recent contribution of neuroimaging tools on the diagnosis, characterization and pathogenesis of FTLD., Evidence Acquisition: Scopus, Ovid, PubMed and MEDLINE were searched for articles published from January 2012 up to December 2014. Searches were limited to articles published in English. Frontotemporal lobar degeneration as a key word was always in the search queries in combination with logic AND, and at least one other key word., Evidence Synthesis: We found 91 papers of interest and reviewed their contents, finding in particular 4 major topics: the contribution of neuroimaging on the differential diagnosis; patients' functional characterization; new neuroimaging tools under development and pre-symptomatic genetic forms., Conclusions: Neuroimaging techniques have shown to be useful supporting tools in diagnosis, even if not always determinant to reach a conclusive decision, and quite important to identify phenocopies. At the moment, there is not a neuroimaging biomarker that could track the progressive course of dementias and the effect of therapies, but it is possible that in the future Diffusion Tensor Imaging and molecular imaging could fill this void. Monitoring the evolution of the pathology in vivo for at least 5 years is essential, and this would only be possible in a large multicenter study; asymptomatic forms would require even longer observation periods.

Background: Frontotemporal lobar degeneration (FTLD) is a progressive dementia characterized by focal atrophy of frontal and/or temporal lobes caused by mutations in the gene coding for sequestosome 1 (SQSTM1), among other genes. Rare SQSTM1 gene mutations have been associated with Paget's disease of bone, amyotrophic lateral sclerosis, and, more recently, frontotemporal lobar degeneration (FTLD)., Objective: The aim of the study was to determine whether a characteristic pattern of grey and white matter loss is associated with SQSTM1 dysfunction., Methods: We performed a voxel-based morphometry (VBM) study in FTD subjects carrying SQSTM1 pathogenic variants (FTD/SQSTM1 mutation carriers; n = 10), compared with FTD subjects not carrying SQSTM1 mutations (Sporadic FTD; n = 20) and healthy controls with no SQSTM1 mutations (HC/SQSTM1 noncarriers; n = 20). The groups were matched according to current age, disease duration, and gender., Results: After comparing FTD/SQSTM1 carriers with Sporadic FTD, a predominantly right cortical atrophy pattern was localized in the inferior frontal, medial orbitofrontal, precentral gyri, and the anterior insula. White matter atrophy was found in both medial and inferior frontal gyri, pallidum, and putamen. FTD/SQSTM1 carriers compared with HC/SQSTM1 noncarriers showed atrophy at frontal, temporal, and parietal lobes of both hemispheres whereas the MRI pattern found in Sporadic FTD compared with controls was frontal and left temporal lobe atrophy, extending toward parietal and occipital lobes of both hemispheres., Conclusions: These results suggest that fronto-orbito-insular regions including corticospinal projections as described in ALS are probably more susceptible to the damaging effect of SQSTM1 mutations delineatinga specific gene-linked atrophy pattern.

Aims: Alexithymia is a personality trait that consists of difficulty in identifying and acknowledging one's own and others' feelings. Recent studies reported that alexithymia is present in both anorexia (AN) and bulimia nervosa (BN). Brain morphological studies on healthy subjects showed that alexithymia correlates with several brain regions involved in emotions processing. The aim of this study was to investigate the anatomical correlates of alexithymia in AN and BN., Methods: We performed a voxel-based morphometry study on 21 patients with AN and 18 with BN. Seventeen healthy subjects were used as a control group. Alexithymia, depression and anxiety were assessed with self-administered questionnaires and correlated to gray matter (GM) density in each group., Results: In BN, alexithymia was correlated with the GM of the parietal lobe, in particular of the right angular gyrus. The correlation was predominantly linked with Difficulty Describing Feelings. In AN, we did not find correlations between GM and alexithymia., Conclusions: In BN, our results support the hypothesis that this trait may represent a relevant pathogenic or maintenance factor that contributes to relational difficulties, present in this pathology. In AN, the lack of correlation between GM volume and alexithymia may be influenced by atrophy in several brain regions that in turn can be, as previously reported, a consequence of caloric restriction. Also, the nature of alexithymia may be different from that of BN and controls and this trait could be secondary to a psychopathologic process specific to AN., (© 2015 The Authors. Psychiatry and Clinical Neurosciences © 2015 Japanese Society of Psychiatry and Neurology.)

Hyperfamiliarity for unknown faces is a rare selective disorder that consists of the disturbing and abnormal feeling of familiarity for unknown faces, while recognition of known faces is normal. In one such patient we investigated with a multimodal neuroimaging design the hitherto undescribed neural signature associated with hyperfamiliarity feelings. Behaviorally, signal detection methods revealed that the patient's discrimination sensitivity between familiar and unfamiliar faces was significantly lower than that of matched controls, and her response criterion for familiarity decisions was significantly more liberal. At the neural level, while morphometric analysis and single-photon emission CT (SPECT) showed the atrophy and hypofunctioning of the left temporal regions, functional magnetic resonance imaging (fMRI) revealed that hyperfamiliarity feelings were selectively associated to enhanced activity in the right medial and inferior temporal cortices. We therefore characterize the neurofunctional signature of hyperfamiliarity for unknown faces as related to the loss of coordinated activity between the complementary face processing functions of the left and right temporal lobes.

Recent studies focussing on neuroimaging features of eating disorders have observed that anorexia nervosa (AN) is characterized by significant grey matter (GM) atrophy in many brain regions, especially in the cerebellum and anterior cingulate cortex. To date, no studies have found GM atrophy in bulimia nervosa (BN) or have directly compared patients with AN and BN. We used voxel-based morphometry (VBM) to characterize brain abnormalities in AN and BN patients, comparing them with each other and with a control group, and correlating brain volume with clinical features. We recruited 17 AN, 13 BN and 14 healthy controls. All subjects underwent high-resolution magnetic resonance imaging (MRI) with a T1-weighted 3D image. VBM analysis was carried out with the FSL-VBM 4.1 tool. We found no global atrophy, but regional GM reduction in AN with respect to controls and BN in the cerebellum, fusiform area, supplementary motor area, and occipital cortex, and in the caudate in BN compared to AN and controls. Both groups of patients had a volumetric increase bilaterally in somatosensory regions with respect to controls, in areas that are typically involved in the sensory-motor integration of body stimuli and in mental representation of the body image. Our VBM study documented, for the first time in BN patients, the presence of volumetric alterations and replicated previous findings in AN patients. We evidenced morphological differences between AN and BN, demonstrating in the latter atrophy of the caudate nucleus, a region involved in reward mechanisms and processes of self-regulation, perhaps involved in the genesis of the binge-eating behaviors of this disorder., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

The idea of a 'pain matrix' specifically devoted to the processing of nociceptive inputs has been challenged. Alternative views now propose that the activity of the primary and secondary somatosensory cortices (SI, SII), the insula and cingulate cortex may be related to a basic defensive system through which significant potentially dangerous events for the body's integrity are detected. By reviewing the role of the SI, SII, the cingulate and the insular cortices in the perception of nociceptive and tactile stimuli, in attentional, emotional and reward tasks, and in interoception and memory, we found that all these task-related networks overlap in the dorsal anterior cingulate cortex, the anterior insula and the dorsal medial thalamus. A thorough analysis revealed that the 'pain-related' network shares important functional similarities with both somatomotor-somatosensory networks and emotional-interoceptive ones. We suggest that these shared areas constitute the central part of an adaptive control system involved in the processing and integration of salient information coming both from external and internal sources. These areas are activated in almost all fMRI tasks and have been indicated to play a pivotal role in switching between externally directed and internally directed brain networks.

Background: Autism spectrum disorder (ASD) is defined on a clinical basis by impairments in social interaction, verbal and non-verbal communication, and repetitive or stereotyped behaviours. Voxel based morphometry (VBM), a technique that gives a probabilistic measure of local grey matter (GM) and white matter concentration, has been used to study ASD patients: modifications in GM volume have been found in various brain regions, such as the corpus callosum, brainstem, amygdala, hippocampus and cerebellum. However, the findings are inconsistent with respect to the specific localisation and direction of GM modifications, and no paper has attempted to statistically summarise the results available in the literature., Methods: The present study is a quantitative meta-analysis of the current VBM findings aimed at delineating the cortical regions with consistently increased or reduced GM concentrations. The activation likelihood estimation (ALE) was used, which is a quantitative voxel based meta-analysis method which can be used to estimate consistent activations across different imaging studies. Co-occurrence statistics of a PubMed query were generated, employing 'autism spectrum disorder' as the neuroanatomical lexicon., Results: Significant ALE values related to GM increases were observed bilaterally in the cerebellum, in the middle temporal gyrus, in the right anterior cingulate cortex, caudate head, insula, fusiform gyrus, precuneus and posterior cingulate cortex, and in the left lingual gyrus. GM decreases were observed bilaterally in the cerebellar tonsil and inferior parietal lobule, in the right amygdala, insula, middle temporal gyrus, caudate tail and precuneus and in the left precentral gyrus.

Brain alterations are known to be associated with anorexia nervosa (AN) and tend to be distributed across brain structures, with only a few reports describing focal damage. Magnetic resonance images of 21 anorexic patients with different disease duration and 27 control subjects were acquired and compared using voxel-based morphometry (VBM). Patients had a significant reduction of total white matter (WM) volume and focal gray matter (GM) atrophy in cerebellum, hypothalamus, caudate nucleus and frontal, parietal and temporal areas. The cerebellum was more affected in patients with longer disease duration, whereas the hypothalamic alterations were more pronounced in patients with shorter food restriction. A correlation with body mass index (BMI) and GM was found in the hypothalamus. Our data demonstrate a diffuse reduction of WM together with focal areas of GM atrophy in AN. The finding of a hypothalamic focal atrophy points to hormonal dysfunction and opens the possibility for a central dysregulation of homeostasis. The involvement of temporoparietal areas could account for body image distortion. Finally, the cerebellar GM atrophy confirms previous findings and seems to be a late consequence of AN that could play a role in the chronic phase of the disease., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

We investigated the characteristics of route and survey processing of a unique complex virtual environment both at the behavioral and brain levels. Prior to fMRI scanning, participants were trained to follow a route and to learn the spatial relationships between several places, acquiring both route and survey knowledge from a ground-level perspective. During scanning, snapshots of the environment were presented, and participants were required to either indicate the direction to take to follow the route (route task), or to locate unseen targets (survey task). Data suggest that route and survey processing are mainly supported by a common occipito-fronto-parieto-temporal neural network. Our results are consistent with those gathered in studies concerning the neural bases of route versus survey knowledge acquired either from different perspectives or in different environments. However, rather than arguing for a clear distinction between route and survey processing, "mixed" strategies are likely to be involved when both types of encoding take place in the same environment.

We examined the functional changes in the activity of the cerebral areas involved in motor tasks, prior to and following a 1-week period of locomotor attention training consisting of physical and mental practice, in normal subjects. In a previous study, we examined the effect of the same kind of training on motor circuits using an fMRI paradigm of motor imagery. In this work, we investigated whether the expanded activations found in the previous study were present also using an overt foot motor task consisting of ankle dorsiflexion; a control task requiring hand movements was also administered. In this article, we also discuss the changes in functional connectivity between the pretraining and posttraining conditions during foot movements. The foot task showed a posttraining reorganization of the sensorimotor areas, which is in line with earlier studies on lower limb motor learning, while the control hand movement task only produced a modification in the left premotor cortex. These results confirm the effect of training on functional reorganization and underline its task specificity. After training, we also observed enhanced connectivity in the sensorimotor areas, suggesting that functional connectivity of the sensorimotor network can be modulated by focusing attention on the movements involved in ambulation.

In brain/head-and-neck radiotherapy (RT), thermoplastic immobilization masks guarantee reproducible patient positioning in treatment position between MRI, CT, and irradiation. Since immobilization masks do not fit in the diagnostic MR head/head-and-neck coils, flexible surface coils are used for MRI imaging in clinical practice. These coils are placed around the head/neck, in contact with the immobilization masks. However, the positioning of these flexible coils is technician dependent, thus leading to poor image reproducibility. Additionally, flexible surface coils have an inferior signal-to-noise-ratio (SNR) compared to diagnostic coils. The aim of this work was to create a new immobilization setup which fits into the diagnostic MR coils in order to enhance MR image quality and reproducibility. For this purpose, a practical immobilization setup was constructed. The performances of the standard clinical and the proposed setups were compared with four tests: SNR, image quality, motion restriction, and reproducibility of inter-fraction subject positioning. The new immobilization setup resulted in 3.4 times higher SNR values on average than the standard setup, except directly below the flexible surface coils where similar SNR was observed. Overall, the image quality was superior for brain/head-and-neck images acquired with the proposed RT setup. Comparable motion restriction in feet-head/left-right directions (maximum motion ≈1 mm) and comparable inter-fraction repositioning accuracy (mean inter-fraction movement 1 ± 0.5 mm) were observed for the standard and the new setup. [ABSTRACT FROM AUTHOR]

Background: The spontaneous component of neuropathic pain (NP) has not been explored sufficiently with neuroimaging techniques, given the difficulty to coax out the brain components that sustain background ongoing pain. Here, we address for the first time the correlates of this component in an fMRI study of a group of eight patients suffering from diabetic neuropathic pain and eight healthy control subjects. Specifically, we studied the functional connectivity that is associated with spontaneous neuropathic pain with spatial independent component analysis (sICA). Principal Findings: Functional connectivity analyses revealed a cortical network consisting of two anti-correlated patterns: one includes the left fusiform gyrus, the left lingual gyrus, the left inferior temporal gyrus, the right inferior occipital gyrus, the dorsal anterior cingulate cortex bilaterally, the pre and postcentral gyrus bilaterally, in which its activity is correlated negatively with pain and positively with the controls; the other includes the left precuneus, dorsolateral prefrontal, frontopolar cortex (both bilaterally), right superior frontal gyrus, left inferior frontal gyrus, thalami, both insulae, inferior parietal lobuli, right mammillary body, and a small area in the left brainstem, in which its activity is correlated positively with pain and negatively with the controls. Furthermore, a power spectra analyses revealed group differences in the frequency bands wherein the sICA signal was decomposed: patients' spectra are shifted towards higher frequencies. Conclusion: In conclusion, we have characterized here for the first time a functional network of brain areas that mark the spontaneous component of NP. Pain is the result of aberrant default mode functional connectivity. [ABSTRACT FROM AUTHOR]