Severe cerebellar atrophy following acute cerebellitis.

The clinical course and serial magnetic resonance imaging findings of a 4-year-old girl with acute cerebellar ataxia due to acute cerebellitis are described. Multifocal white matter lesions visualized by magnetic resonance imaging in both cerebellar hemispheres in the acute phase disappeared in the convalescent phase. Cerebellar signs became less prominent within 2 weeks, but mild ataxic gait remained. During the follow-up period of 32 months, there was a gradual development of cerebellar atrophy along with a recurrence of cerebellar ataxia.