Figure 11: A 22-year-old female with hereditary motor sensory neuropathy (HMSN). A, Coronal fat-suppressed T2-weighted MR image shows marked asymmetric thickening and disruption of normal internal fascicular architecture of the BP; on the right, from root to cord level and on the left, mildly thickened upper trunk (arrows). B, Axial T2-weighted MR image at the level of right mid forearm shows marked atrophy with fatty replacement (arrows) of the muscles.