Assessment of the cerebral blood flow using single photon emission computed tomography and digital subtraction angiography in patients with internal carotid artery occlusion

Abstract

  The examination of cerebral blood flow (CBF) is very important in patients with occlusion of the internal carotid artery on one side. Single photon emission computed tomography (SPECT) and digital subtraction angiography (DSA) have been used to assess CBF. In this study, we performed cerebrovascular examination to investigate the collateral pathway in patients who underwent SPECT with unilateral internal carotid artery occlusion. We observed the ratio between the contralateral side and the ipsilateral side using quantitative resting CBF. Twenty‒eight patients with unilateral internal carotid artery occlusion (mean age: 69.1 years) underwent SPECT. DSA also showed us the collateral pathway. In the SPECT, the brain was classified into 52 areas by 3D automatic region analysis. In 24 cases, DSA revealed that the collateral pathway included in 79% via the posterior communicating artery, in 71% via the anterior communicating artery, in 42% via the external carotid artery, and in 38% via leptomeningeal anastomosis. In the 28 cases that underwent SPECT, the CBF lowering region was found in the angular gyrus.