[Correlation of clinical course with MRI findings in olivo-pontocerebellar atrophy and late-cortical cerebellar atrophy].

We quantitatively analyzed 1.5 T MRI in 36 cases of sporadic spinocerebellar degeneration (SCD) and 30 control cases without intracranial lesions, using graphic analyzer. SCD consisted of 21 olivo-ponto-cerebellar atrophy (OPCA) and 15 late cortical cerebellar atrophy (LCCA). There was negative correlation between vermian size and the duration of illness both in OPCA (r = 0.8960, p less than 0.001) and LCCA (r = 0.7756, p less than 0.01), but the progression rate in OPCA was three times greater than that in LCCA. LCCA was suggested the preclinical vermian atrophy by the statistical regression study. In OPCA, the duration of illness also revealed significant correlations with atrophy of ventral pons (r = 0.8308, p less than 0.001) and also cerebellar hemisphere (medial hemisphere; r = 0.7278, p less than 0.001. lateral hemisphere; r = 0.6039, p less than 0.01). OPCA showed diffuse atrophy of cerebellar hemisphere, whereas LCCA showed medial dominant atrophy. OPCA demonstrated significant correlation between the fourth ventricle dilatation and the duration of illness (r = 0.6005, p less than 0.01). A discriminant study significantly separated OPCA, LCCA and control each other by sizes of ventral pons and cerebellar vermis (p less than 0.001). In T2 weighted MRI, 10 cases out of 14 LCCA did not show hypointensity in dentate nucleus in spite of normal appearance in the other portions usually decreased intensity. The dentate nucleus of OPCA showed a significant atrophy. The incidence of putaminal hypointensity in OPCA was significantly greater than that of control group (chi-square = 6.476, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)