Alternating hemiplegia in childhood: a cross-sectional study.

Six patients with alternating hemiplegia in childhood (AHC) were followed, some of them up to childhood. Progressive intellectual deterioration and disturbance of pyramidal, extrapyramidal and cerebellar functions were found in all of them. Multimodal evoked potential abnormalities, changes of sleep structure and HMPAO-SPECT results were correlated with increasing clinical handicap.