Abstract
Although many case reports of aphasia following left putaminal hemorrhages have been accumumulated, the mechanism of these language disorders has not yet been clarified. In this report, 41 patients with left putaminal hemorrhages were studied to compare the language disorders with the regional cerebral blood flow(rCBF) measured with single photon emission CT. The following conclusions were obtained :
1) Examination of language revealed 10 nonaphasics and 31 aphasics. Almost all of the aphasics showed a tendency for language disorders in the expressive aspect (fluency) and the receptive aspect (comprehension) to be equal in degree.
2) Low blood flow areas revealed by emission CT were larger than lesions by X-ray CT and they involved remote surface areas of perfusion territory of the left middle cerebral artery (MCA). Appearance of aphasia was more related to the blood flow change in this cortical area than to that in area of the basal ganglia. Fluency disorders correlated with the rCBF value in the anterior part of the perfusion territory of the left MCA (aMCA) which included Broca's area. Comprehension disorders correlated with the rCBF value in the posterior part of the perfusion territory of the left MCA (pMCA), including Wernicke's area. Such disorders were observed in 12 aphasic patients following left cerebral infarction. Moreover, the decreases of rCBF values in the aMCA and pMCA of hemorrhagic patients were equal in degree.
3) As the possible causes for rCBF change in the surface of the hemisphere, several factors had to be considered such as mass effect, secondary irreversible brain damage from mass effect and transneural effect.
