GAD2 and Atrophy/Degeneration affecting the brainstem: Of these 62 patients, the most common finding was brainstem T2 hyperintensity (n = 30, 31%); followed by cerebellar atrophy (n = 27, 28%), cerebellar T2 hyperintensity (n = 9, 9%), brainstem atrophy (n = 6, 6%), and hypertrophic olivary degeneration (n = 3, 3%; KLHL‐11‐IgG [2], GAD65‐IgG [1]).