Pathological findings. Both cases showed similar gross and microscopic findings, including cerebral atrophy that was more severe on the left and preferentially affected the temporal lobes and primary motor cortex (arrows, Case 2) (A, B). There was moderate-to-severe chronic degeneration of the motor cortex (C) and corticospinal tracts (*, D) with a normal number of healthy-appearing lower motor neurons (E). TDP immunohistochemistry demonstrated neuronal cytoplasmic inclusions (NCI) in all cortical laminae of the primary motor (F), prefrontal (G) and temporal neocortex with relatively few dystrophic neurites and no intranuclear inclusions, consistent with FTLD-TDP type B. Many of the NCI had an unusual crescentic, annular or tangle-like morphology. NCI were also abundant in the basal ganglia (H). Magnifications: C:100x; D:20x; E:200x; F,G and H:600x.