Determinants of Deep Gray Matter Atrophy in Multiple Sclerosis: A Multimodal MRI Study.

BACKGROUND AND PURPOSE: Deep gray matter involvement is a consistent feature in multiple sclerosis. The aim of this study was to evaluate the relationship between different deep gray matter alterations and the development of subcortical atrophy, as well as to investigate the possible different substrates of volume loss between phenotypes. MATERIALS AND METHODS: Seventy-seven patients with MS (52 with relapsing-remitting and 25 with progressive MS) and 41 healthy controls were enrolled in this cross-sectional study. MR imaging investigation included volumetric, DTI, PWI and Quantitative Susceptibility Mapping analyses. Deep gray matter structures were automatically segmented to obtain volumes and mean values for each MR imaging metric in the thalamus, caudate, putamen, and globus pallidus. Between-group differences were probed by ANCOVA analyses, while the contribution of different MR imaging metrics to deep gray matter atrophy was investigated via hierarchic multiple linear regression models. RESULTS: Patients with MS showed a multifaceted involvement of the thalamus and basal ganglia, with significant atrophy of all deep gray matter structures (P < .001). In the relapsing-remitting MS group, WM lesion burden proved to be the main contributor to volume loss for all deep gray matter structures (P ≤ .006), with a minor role of local microstructural damage, which, in turn, was the main determinant of deep gray matter atrophy in patients with progressive MS (P ≤ .01), coupled with thalamic susceptibility changes (P = .05). CONCLUSIONS: Our study confirms the diffuse involvement of deep gray matter in MS, demonstrating a different behavior between MS phenotypes, with subcortical GM atrophy mainly determined by global WM lesion burden in patients with relapsing-remitting MS, while local microstructural damage and susceptibility changes mainly accounted for the development of deep gray matter volume loss in patients with progressive MS.

Endosonographic diagnosis of submucosal upper gastrointestinal tract lesions and large fold gastropathies by catheter ultrasound probe.

BACKGROUND: The unique ability of EUS to depict wall layers makes it possible to accurately evaluate submucosal lesions of the digestive tract and large-fold gastropathies. Although EUS requires a second endoscopic examination, miniature US probes introduced through the accessory channel of a conventional endoscope permit US examination during routine endoscopy. METHODS: By means of catheter probe sonography and conventional EUS, we evaluated 33 patients with a radiographic or endoscopic finding of a submucosal lesion of the upper GI tract or with large-fold gastropathies and histologically negative biopsies obtained at a previous endoscopy. A miniature multifrequency probe was used for catheter probe sonography. RESULTS: For 25 submucosal lesions catheter probe sonography results were superimposable on those obtained with EUS. In evaluating submucosal lesions, catheter probe sonography yielded the same results as conventional EUS in terms of depiction, measurement, and identification of the originating layer of the tumor. In the study of 8 large-fold gastropathies, catheter probe sonography missed the presence of ascites and enlarged lymph nodes in a case of gastric linitis, but produced the same results as conventional EUS in the other cases. CONCLUSIONS: For the evaluation of benign submucosal lesions and large-fold gastropathies, catheter probe sonography appears to be sufficient and could thus replace conventional EUS for these indications.