- The Impact of Intracortical Lesions on Volumes of Subcortical Structures in Multiple Sclerosis
The authors investigated the impact of intracortical lesions on the volumes of subcortical structures (especially the thalamus) compared with other lesions in 71 patients with MS. The volumes of intracortical lesions and white matter lesions were identified on double inversion recovery and FLAIR imaging, respectively, by using 3D Slicer. Volumes of white matter T1 hypointensities and subcortical gray matter, thalamus, caudate, putamen, and pallidum volumes were calculated using FreeSurfer. They conclude that thalamic atrophy was explained better by intracortical lesions than by white matter lesion and T1 hypointensity volumes, especially in patients with more profound disability.
- Cerebellar Watershed Injury in Children
Focal signal abnormalities at the depth of the cerebellar fissures in children have been reported and hypothesized to represent a novel pattern of bottom-of-fissure dysplasia. The authors report a series of 23 patients with a similar distribution and appearance of cerebellar signal abnormality attributable to watershed injury. T2 prolongation was observed at the depths of the cerebellar fissures bilaterally in all 23 patients, centered at the expected location of the deep cerebellar vascular borderzone. Diffusion restriction was associated with MR imaging performed during acute injury in 13/16 patients. Five of 23 patients had prior imaging, all demonstrating a normal cerebellum. The etiology of injury was hypoxic-ischemic injury in 17/23 patients, posterior reversible encephalopathy syndrome in 3/23 patients, and indeterminate in 3/23 patients.
- Sensitivity of the Inhomogeneous Magnetization Transfer Imaging Technique to Spinal Cord Damage in Multiple Sclerosis
Anatomic images covering the cervical spinal cord from the C1 to C6 levels and DTI, magnetization transfer/inhomogeneous magnetization transfer images at the C2/C5 levels were acquired in 19 patients with MS and 19 paired healthy controls. Anatomic images were segmented in spinal cord GM and WM, both manually and using the AMU40 atlases. MS lesions were manually delineated. MR imaging metrics were analyzed within normal-appearing and lesion regions in anterolateral and posterolateral WM and compared using Wilcoxon rank tests and z scores. The use of a multiparametric MR imaging protocol combined with an automatic template-based GM/WM segmentation approach in the current study outlined a higher sensitivity of the ihMT technique toward spinal cord pathophysiologic changes in MS compared with atrophy measurements, DTI, and conventional MT. The authors also conclude that the clinical correlations between ihMTR and functional impairment observed in patients with MS also argue for its potential clinical relevance, paving the way for future longitudinal multicentric clinical trials in MS.