Fig. 2

Degenerative changes in the patient’s cerebellar cortex (b, c, e, f, h, i) compared with a control (a, d, g) with LH&E stain (a-c), Bielschowsky stain (d-f) and calbindinD_28k immunostain (g-i). The molecular layer is thinner (b) and there is marked Purkinje cell loss with scattered, often atrophic Purkinje cells (b, c, white arrows) and Bergmann gliosis (b, c). Basket cell processes are coarse (e, yellow arrows), often around extant or atrophic (f, white arrow) Purkinje cells, and basket cell processes may be largely absent (e, yellow bars). Compared with control Purkinje cells (g), the patient’s Purkinje cell dendritic arbors are often stunted (h, i) and axonal changes including torpedoes (c, f, h, i, large black arrows), axonal branching (H, small black arrows) and recurrent collaterals (h, i, carets) are increased. Scale bars: 100 μm, A, B, D, E; 50 μm, C, F; 100 μm, G-H