[Paroxysmal cerebellar ataxia--an evaluation using the findings from magnetic resonance imaging, positron emission tomography, and acetazolamide treatment].

Paroxysmal cerebellar ataxia (PCA) is a specific disease which exhibits spasmodic cerebellar ataxia but rarely shows abnormal neurological findings in the intermission. Verger first described an isolated case. Subsequent reports of the disease included mostly cases with autosomal dominant inheritance, but the reports have been limited to about 20 families. Although both the lesion and the cause have not been clearly identified, since Vighetto et al. demonstrated the atrophy of the anterosuperior region of the cerebellar vermis using magnetic resonance imaging (MRI), the lesion of PCA captured the attention of researchers. The patient was a 40-year-old male, who exhibited spasmodic inarticulation and dizziness during walking when he was 10 years old. The symptoms gradually became aggravated in both frequency and duration. Abnormal findings were observed by electroencephalography and Hydantol F was given with no successful effect. The results of a CT scan of the head revealed no abnormality, whereas those of MRI revealed the atrophy in the folia of anterosuperior region of the cerebellar vermis by MRI as in the case of Vighetto et al., and PCA was suspected. Findings from positron emission tomography (PET) for the first time disclosed the abnormality in the cerebellar vermis and brainstem, and suggested an organic disorder in the cerebellar vermis and a functional abnormality in the cerebellum and brainstem. Since the report by Griggs et al., it has been known that acetazolamide is effective for PCA although the pharmacological mechanism is not yet clear. In our present case, the attack was improved in both frequency and duration by the administration of acetazolamide, and the effectiveness of acetazolamide in the patient was confirmed.(ABSTRACT TRUNCATED AT 250 WORDS)