DEGENERATIVE DISEASE OF THE SUBTHALAMIC BODIES*t

The literature on lesions of the subthalamic body or corpus Luysi has largely concerned itself with unilateral involvement of this nucleus as manifested clinically by the syndrome of hemiballismus. In an exhaustive review of the literature, Whittier (1) found 30 cases of hemiballismus associated with isolated lesions in the subthalamic body. In the majority these were of a vascular nature. Bilateral involvement of the subthalamic body, on the other hand, has generally been observed as a part of more diffuse pathologic conditions, for example, kernicterus and encephalitis. In the group of heredodegenerative diseases, rare involvement of the subthalamic bodies has been reported, but again only in combination with lesions in other systems. Here belong a case of ballismus associated with cerebellar ataxia reported by Titica and van Bogaert (2), a case with Huntington's chorea by Meszaros (3), and a case with spastic paraplegia by Baumann (4). In all of these instances, the ballistic movements, as might be expected, were modified by the coexisting lesions in other systems. The only exception appears to be the case reported clinically by Rakonitz (5) in 1933. It concerned a man who, over a ten year period, from the age of 40 to 50 years suffered from symptoms of a slowly progressive ballismus, dysarthria, and dysphagia. The most prominent neurologic signs were bilaterally symmetrical rhythmic, rapid, hurling and rotating involuntary movements, that affected most severely the head, trunk and proximal muscles of the extremities, and were accompanied by fluctuations in muscle tone. The family history showed evidence of a similar disorder in an older brother, maternal grandfather and sister of the latter. It was the opinion of Rakonitz that his was the first reported case of hereditary biballismus and that the underlying lesion was a symmetrical degeneration of the corpus Luysi. The case, however, loses some of its significance in view of the lack of pathoanatomic confirmation. The following 3 cases are, therefore, presented as the first recorded instances of a degenerative disease of the subthalamic bodies, which has been verified postmortem.