Clinical study of subcortical aphasia using brain SPECT and neurolinguistical methods

ABSTRACT

BACKGROUND & PURPOSE: Subcortical aphasia is derived from infarction, hemorrhage or tumor in subcortical area, such as striatocpsular region, thalamus, paraventricualr white matter and corona radiata. To our knowledge, there have been few studies on subwrtical aphasia in Korea. OBJECTIVE: 1) To evaluate various lesion sites and clinical features associated with subcortical aphasia. 2) To evaluate type and characteristics of subcortical aphasia by Modified Western Aphasia Battery(MWAB) test. 3)To predict the mechanisms of subcortical aphasia and to relate type of aphasia to hypoperfusion are a ascertained by brain SPECT. METHODS: We analysed 19patients wing brain CT/MRI and neurolinguistical method of MWAB, who presented language disturbance of aphasic nature due to subcortical strokes. Cerebral blood flow was measured in 10 out of 19 patients using brain SPECT. RESULTS & CONCLUSION: 1) The lesion sites responsible for subcortical aphasia were caudate nucleus, putamen, internal capsule, thalamus, paraventricular white matter and corona radiata. Hemiparesis and dysarthria were more common in subcortical aphasia than in cortical one. 2) Subcortical aphasia was characterized by higher incidence of anomic type and more rapid recovery than cortical aphasia. Most subcortical aphasia following thalamic lesions revealed characteristic features of Preservation of repetition and prominent deficits in naming. 3) Ten cases of subcortical aphasia showed both cortical and subcortical hypoperfusion, suggesting that subcortical aphasia be derived from secondary hypoperfusion of the cortical language area. In most of the patients, the types and severity of subcortical aphasia correlated with the location and extent of cortical hypoperfusion area.