Knowledge regarding various types of atrophy of the cerebellum is still sadly incomplete. An attempt was made in a previous contribution1 to bring up to date a report on the literature describing a particular type of atrophy, and the clinical and pathologic details of one new case were described. At that time it seemed as if there was a certain degree of uniformity in the descriptions of the disease; more careful scrutiny of the reported cases, however, suggested the advisability of further divisions in the classification. Accordingly, in view of this, and considering the scanty knowledge of the subject, we thought it worth while to review this type of atrophy once more, especially in the light of our recent experience.
Parenchymatous cortical cerebellar atrophy is a rare disease. We were able to find only twelve well authenticated cases reported in the literature wherein both clinical and pathologic details were