Perfusion Computed Tomography in a Rabbit Model with Acute Ischemic Infarction: Comparison with Perfusion MR Imaging

Shin, Sang Soo; Seo, Jeong Jin; Yim, Nam Yeol; Jeong, Gwang Woo; Yoon, Woong; Lim, Hyo Soon; Jeong, Yong Yeon; Chung, Tae Woong; Kim, Yun Hyeon; Kang, Heoung Keun

Abstract

The present study was undertaken to evaluate the usefulness and the difference between cerebral perfusion L-weighted MR imaging (PW-MRI) and perfusion CT (P-CT) in rabbit model of acute cerebral ischemic infarction. Experimental cerebral infarction was induced by direct injection of mixture of histoacryl glue, lipiodol, and tungsten powder into the internal cerebral artery of 4 New-Zealand white rabbits. MRI and PW-MRI and sequential P-CT were evaluated within 1 hour after the occlusion of internal cerebral artery. The PW-MRI and P-CT scan was obtained at the level of lateral ventricle and 1 cm cranial to the basal ganglia. By postprocessing using special imaging software, perfusion images including cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time to peak (TTP) maps were obtained. The area of perfusion deficit on each map was measured. MTT and TTP delay were calculated by the time difference between peak time of infarcted lesion and normal contralateral region on MTT and TTP maps. The detection of infarcted lesion was evaluated on each perfusion map and T2-weighted MR imaging (T2WI). In all rabbits, all P-CT and PW-MRI maps showed the perfusion defect lesion. But T2WI and CT scan did not reveal any abnormal lesion. No remarkable difference was found in the measured area of infarcted lesion of CBV and CBF maps between P-CT and PW-MRI. Nor was there any no difference in the time calculated MTT and TTP delay of perfusion defect lesion between P-CT and PW-MRI, suggesting that either P-CT or PW-MRI may be useful in diagnosing acute cerebral ischemic infarction and in evaluating the cerebral hemodynamics.