[Olivopontocerebellar atrophy: clinical analysis of 100 cases]

The clinical features in 100 patients suffered from olivopontocerebellar atrophy (OPCA) and their genetic trait were studied. The diagnosis was verified in all cases with computed tomography, demonstrating the atrophy of cerebellum and brainstem, vascular, neoplastic, infectious and any other organic disorder suspected were excluded. 53 out of 100 cases were sporadic (SOPCA) and the remainder (47 cases) was familial (FOPCA). The age of onset in SOPCA group was 36.1 +/- 14.95 (M +/- SD) in average, while in FOPCA group was 28.9 +/- 11.8. It seems that the symptoms in FOPCA group develop earlier than that in SOPCA group (P less than 0.05). All 47 cases of FOPCA group belong to 36 families in which altogether 166 persons were involved. According to pedigree patterns, there were 26 families inherited as autosomal dominant trait and probably so in another 5 families. Autosomal recessive trait could be confirmed in 2 families, in which the parents of proband were consanguineous, and in 3 other families autosomal recessive trait of inheritance was highly suspected. Anticipation was demonstrated in 26 families with dominant inheritance. Generally, ataxia and weakness of legs develop as initial symptoms in 88% of cases, then followed by dysarthria, and ataxia of upper extremities. The rapid alternating test of hand was impaired in 95% of patients, however, tension tremor was revealed only in 53% of patients. A method for assessing the ataxia quantitatively was proposed, our data suggest that the quantitative alternating test in the upper extremity and the measurement of base-width in lower extremity seem to be valuable in identifying the intensity of ataxia.