Evaluation of vertical RI-angiography in occlusive cerebrovascular disease

Radioisotope angiography in vertex view was performed on 11 patients with left internal carotid artery occlusion, 11 patients with left middle cerebral artery occlusion, 9 patients with right ICA occlusions, 9 patients with right MCA occlusion and 10 controls. 99m-Technetium pertechnetate was injected intravenously and dynamic images were recorded. Five pairs of ROI were drawn symmetrically in frontal, temporal, central, occipital and total region of each hemisphere and the time activity curve of each ROI was made and analysed. The four parameters which were obtained from these time activity curves were peak count, appearance to peak time, mean transit time and upward slope. Peak time and upward slope were compared between the hemispheres. The upward slope ratio was great in almost all pairs of ROI in patients with ICA occlusion, but in patients with MCA occlusion it was great only in temporal and central regions but not so great in frontal and occipital regions. The changes in the other three parameters were not constant