Introduction
Of the various cerebellar disorders focal cortical cerebellar sclerosis must be separated from the more diffuse degenerations of the cerebellar cortex. Focal cortical cerebellar sclerosis is found as a chance postmortem finding in patients who have had no obvious signs or symptoms of cerebellar disease during life. It has been associated with many different disease states, but not consistently enough with any particular one to provide etiological clues. Its cause is unknown. The areas of involvement are circumscribed, asymmetrical and of varying size, usually located in the superior, lateral and posterior aspect of the cerebellar hemispheres, specifically in the superior and inferior semilunar lobules and the simple lobule. Histologically, the lesion is reported as characterized by a loss of all parenchymatous elements in the Purkinje, granular and molecular layers, and of the myelin and axis cylinders of the underlying white matter with proliferation of fibrous astrocytes in all areas,