Cerebral blood flow disturbances after anterior choroidal artery infarcts. Anatomical and functional correlates

We have investigated the cortical and subcortical regional cerebral blood flow (rCBF) disorders resulting from infarcts of the anterior choroidal artery (AChA), and correlations with the severity of lesions, the physical and cognitive deficits, and the functional impairment. Eighteen patients presenting with recent anterior choroidal artery infarct without any other brain injury were examined at the secondary phase post-stroke using the single photon emission computed tomography technique and 133 Xenon inhalation. The rCBF and asymmetry indexes (AI) were calculated for 12 symmetrical hemispheric areas, and the cerebellum. The AI values were compared with those of 24 control subjects. The severity of the lesions was evaluated from CT scans or MRI. The neurological status (Orgogozo scale, walking disorders, MMSE, attention impairment, aphasia) and disability (functional independance measure: FIM) were assessed for each patient at the same time period. The relationships between rCBF disorders and brain lesions, and between the results of clinical investigations and rCBF disorders and brain lesions were assessed by linear regression analyses (stepwise variable selections, p=0.05). The AI values were significantly increased in the cerebral hemispheres, and this was most severe in the internal capsule (direct effect of the lesion) and the dorsolateral hemispheric cortex (diaschisis). Individual evaluations showed that AI were significantly increased in 13 patients in at least one ROI of the cerebral hemispheres, and in 3 patients in the internal capsule. Stepwise variable selections revealed that AI were best explained by the severity of the lesions in the internal capsule and the internal temporal area. The AI of the external temporal area and the internal capsule also helped explain the clinical (physical and cognitive) deficits. Thus, AChA infarcts may have relatively large effects on the central part of the lateral and dorsal cortex of the ipsilateral hemisphere. Subcortical and cortical consequences both contribute to explain the motor and cognitive deficits and disability.