PATHOLOGY OF THE CEREBELLAR DENTATE AND INTERPOSITUS NUCLEI IN JOSEPH DISEASE - A MORPHOMETRIC INVESTIGATION

Cerebellar dentate and interpositus nuclei pathology was studied morphometrically in 3 patients with Joseph disease compared to 3 control subjects. Size of neurons, number of small neurons (cell body area: 50-199-mu-m2) and large neurons (cell body area: 200-mu-m2 or greater) at the rostral, medial and caudal levels, neuronal cell density, total volume of the gray bands, and total neuronal cell number were evaluated in the dentate, emboliform, and globose nuclei, using an image analyzer, after making horizontal serial 20-mu-m thick sections of a unilateral cerebellar hemisphere embedded in celloidin. The number of large neurons in Joseph disease was around 20% of that in the controls at each level in the individual nucleus (P < 0.05 or P < 0.01). In contrast, the number of small neurons was significantly reduced only at the caudal level of the dentate nucleus (P < 0.05). The neuronal cell density was decreased within the nuclei. The total volume of the gray bands was reduced to about 70% within the nuclei (P < 0.05 or P < 0.01). The total number of neurons was decreased to about a third, a half, and a third within the dentate (P < 0.001), emboliform (P < 0.01), and globose nuclei (P < 0.001), respectively. The principal pathologic change of the dentate and interpositus nuclei in Joseph disease was severe loss of neurons, with significant loss of the large neurons, indicating that Joseph disease is a type of cerebellar efferent system disorder.