Localised grey matter atrophy in multiple sclerosis is network-based: a coordinate-based meta-analysis.

AIM: To test the network degeneration hypothesis in multiple sclerosis (MS) with a two-stage coordinate-based meta-analysis by: (1) characterising regional selectivity of grey matter (GM) atrophy and (2) testing for functional connectivity involving these regions. MATERIALS AND METHODS: Meta-analytic sources included 33 journal articles (1,666 MS patients and 1,269 healthy controls) with coordinate-based results from voxel-based morphometry analysis demonstrating GM atrophy. Mass univariate and multivariate coordinate-based meta-analyses were performed to identify a convergent pattern of GM atrophy and determine inter-regional co-activation (as a surrogate of functional connectivity), with anatomical likelihood estimation and functional meta-analytic connectivity modelling, respectively. RESULTS: Localised GM atrophy was demonstrated in the thalamus, putamen, caudate, sensorimotor cortex, insula, superior temporal gyrus, and cingulate gyrus. This convergent pattern of atrophy displayed significant inter-regional functional co-activations. CONCLUSION: In MS, GM atrophy was regionally selective, and these regions were functionally connected. The meta-analytic model-based results of this study are intended to guide future development of quantitative neuroimaging markers for diagnosis, evaluating disease progression, and monitoring treatment response.

Characterisation of meta-analytical functional connectivity in progressive supranuclear palsy.

AIM: To characterise the meta-analytical functional connectivity patterns in progressive supranuclear palsy (PSP) and compare them to idiopathic Parkinson's disease (IPD). MATERIALS AND METHODS: It was previously reported that PSP and IPD showed distinct regions of brain atrophy based on voxel-based morphometry (VBM) meta-analysis. Using these regions as seeds, healthy control data were referenced to create and statistically compare meta-analytical functional connectivity maps of PSP and IPD. RESULTS: Some overlap was noted between the two diseases, including within the thalamus, striatum, and prefrontal cortex; however, the PSP seeds demonstrated more extensive functional co-activity throughout the brain, particularly within the midbrain, precentral gyrus, parietal cortex, basal ganglia, and cerebellum. CONCLUSION: These findings may help guide future longitudinal studies in the development of new functional imaging biomarkers for diagnosis and assessing treatment response.

Basion-Cartilaginous Dens Interval: An Imaging Parameter for Craniovertebral Junction Assessment in Children.

BACKGROUND AND PURPOSE: Widening of the basion-dens interval is an important sign of cranioverterbral junction injury. The current literature on basion-dens interval in children is sparse and based on bony measurements with variable values. Our goal was to establish the normal values of a recently described new imaging parameter, the basion-cartilaginous dens interval in children. MATERIALS AND METHODS: Three hundred healthy pediatric patients (0-10 years of age) were selected retrospectively. These patients were divided into 3 different groups: A (0-3 years), B (3-6 years), and C (6-10 years). The basion-cartilaginous dens interval was calculated on the sagittal MPR image of cervical spine CT in a soft-tissue window. The mean, SD, and the upper limit of normal (mean +2 SDs) of the 3 groups were calculated, and statistical tests were used to check for significant differences of the basion-cartilaginous dens interval among these 3 groups. RESULTS: The upper limits of the basion-cartilaginous dens interval for the 3 groups were 5.34 mm in group A, 5.64 mm in group B, and 7.24 mm in group C. There were statistically significant differences in the basion-cartilaginous dens interval values among the 3 groups. There was no statistically significant difference in basion-cartilaginous dens interval values between groups A and B; however, values in group C were significantly different from those in both A and B. There was no statistically significant difference in the basion-cartilaginous dens interval values between males and females. CONCLUSIONS: The basion-cartilaginous dens interval is a novel imaging parameter to assess cranioverterbral junction integrity in children, which includes the nonossified cartilage in the measurement.

Richter transformation of chronic lymphocytic leukemia presenting as a dural-based non-hodgkin lymphoma mass.

Richter transformation is defined as a diffuse large cell lymphoma, occurring by transformation of chronic lymphocytic leukemia (CLL). We present a 64-year-old man with a history of CLL and a left parieto-occipital transtentorial extra-axial mass. The patient underwent CT and MR imaging, demonstrating a large dural-based mass with extracranial extension, which occluded the left transverse sinus. Biopsy of the mass proved a pathologic diagnosis of diffuse large cell non-Hodgkin lymphoma, consistent with Richter transformation of CLL.