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In a prospective study we investigated 106 consecutive patients with sudden onset of dysarthria due to a single, not space-occupying infarction confirmed by MRI. Extracerebellar infarctions (81.1%) were located in the lower part of the primary motor cortex (3.8%), middle part of the centrum semiovale (23.6%), striatocapsular (5.7%), genu and dorsal segment of the internal capsule (11.4%), cerebral peduncle (0.9%), ventral ponto-mesencephalic region (1.9%), base of the pons (23.8%), and the ventral pontomedullary junction (1.9%). Isolated cerebellar infarctions affected the rostral paravermal region in the SCA-territory. Combined extracerebellar and cerebellar infarctions were present in 10.4% of our patients. In extracerebellar infarctions the lesions were more often localized in the left hemisphere as compared with the right hemisphere (77.5% vs 22.5%). Cerebellar infarctions, however, affected the right side in 4 and the left side in 2 patients.Correlating to clinical, electrophysiological, and fMRI-findings, the lesion topography of extracerebellar infarctions underlying dysarhria is consistent with an impairment of volitional movements due to a lesion of the corticobulbar pathways while cerebellar lesions result in impaired coordination of articulatory movements.