[Determination of regional cerebrovascular perfusion reserve (rCPR) using quantitative flow/volume (F/V)-SPECT. Results in patients with subcortical ischemic brain lesions with or without neuropsychological symptoms].

NPS (aphasia or neglect) are a regular concomitant symptom of cortical, and, occasionally, subcortical ischemic lesions. In 19 patients with subcortical lesions (eight with NPS, 11 without NPS), F/V-SPECT was employed to search for changes in rCPR in both, lesions and ipsilateral cortex. Results were correlated with NPS and MRI findings. Compared to the unaffected hemisphere, all subcortical lesions showed reduced regional cerebral blood flow (rCBF) (-16 to -23%), increased regional cerebral blood volume (rCBV) (+34 to +62%), and decreased or missing rCPR (-27 to -28%). Compared to MRI, there was no difference in lesion size in the thromboembolic lesions. Hemodynamic low-flow infarcts, however, were greater with SPECT than in MRI. In patients without NPS, the adjacent cortex was normal in SPECT and MRI. In addition, patients with NPS revealed reduced rCBF (-18%), increased rCBV (+19%), and decreased rCPR (-22%) in the adjacent cortex. MRI was normal in the same cortical area. These results indicate that NPS in subcortical lesions may be caused by a hemodynamic mechanism causing reduction of rCPR in the adjacent cortex.