Regional cerebral blood flow measured with 99mTc-HMPAO based on two-dimensional 133Xe study in ischemic brain.

Two-dimensional regional cerebral blood flow (rCBF) was measured using the xenon-133 inhalation method, and used to calibrate the rCBF measured by single photon emission computed tomography (SPECT) in the non-affected middle cerebral artery (MCA) area. The value of the rCBF in the target area could then be measured by SPECT and compared between patients. Technetium-99m-d,l-hexamethyl-propylene-amine-oxime and technetium-99m-diethylenetriaminepenta-acetic acid-human serum albumin D were used to measure rCBF and regional cerebral blood volume (rCBV), respectively, in the ischemic area of 16 patients who underwent surgical revascularization in the chronic stage. No significant increase in rCBF was obtained after the bypass surgery. The delta rCBF and delta CBF/CBV ratio correlated well with the extent of vascularization in the MCA area on postoperative angiograms. Patients with a low CBF/CBV ratio on preoperative SPECT scans tended to show favorable postoperative vascularization and rCBF in the MCA area. Since the angiographic findings and the delta rCBF or delta CBF/CBV were correlated well, this simple and non-invasive method could be used for the analysis of rCBF in a group of patients.