Post-ischemic hyperperfusion after clipping of a ruptured internal carotid-posterior communicating artery aneurysm under suction decompression

Abstract

Abstract A 64-year-old woman presenting with subarachnoid hemorrhage (World Federation of Neurosurgeons grade IV) from the rupture of a right large internal carotid-posterior communicating artery aneurysm suffered neuronal damage associated with post-ischemic hyperperfusion after neck clipping of the aneurysm under suction decompression. She did not completely recover consciousness after the operation. Diffusion-weighted imaging (DWI) performed on the first postoperative day showed subtle cortical hyperintensity in the parietal lobe. Arterial spin-labeling (ASL) and 123 I-iodoamphetamine ( 123 I-IMP) single photon emission computed tomography (SPECT) demonstrated hyperperfusion in the right temporo-parietal lobes. Delayed 123 I-iomazenil ( 123 I-IMZ) SPECT images showed a reduced IMZ uptake in the right temporo-parietal lobe corresponding to the hyperperfusion area on ASL images. DWI repeated on postoperative day 3 revealed progression of a hyperintensity lesion in the right parietal lobe. Blood pressure control and the use of a free radical scavenger relieved her symptoms. One month later, the area of reduced IMZ uptake was further expanded. Our findings suggest that post-ischemic hyperperfusion after suction decompression may result in neuronal damage demonstrated on 123 I-IMZ SPECT images.