Transitory Hyperaemia in Focal Cerebral Vascular Lesions Studied by Angiography and Regional Cerebral Blood Flow Measurements

In cerebrovascular lesions specific transitory angiographic findings may be present in addition to the usually recognised ones. These specific changes—contrast blush and early filling veins—are transitory. Combined use of cerebral angiography and measurements of the regional cerebral blood flow (rCBF) with the 133Xe-injection method have shown that these transitory angiographic changes are signs of a local relative hyperaemia. This is considered to be a phenomenon due to a local hypoxia secondary to the ischaemic lesion. In cases with a cerebrovascular lesion early vein filling and/or a contrast blush may be the only angiographic changes. Because of this they are of great diagnostic importance. The findings may, however, also give rise to new diagnostic problems as early vein filling, specially in combination with a space-occupying lesion, has generally been considered equal to an arterio-venous shunt signifying a malignant tumour.