Time window of reversible cerebral ischemia in pigs by single photon emission computed tomography
- VernacularTitle:单光子放射型计算机断层显像评估猪脑缺血的可逆性时相窗
- Author:
Chengming XING
;
Feibo ZHENG
;
Xinming LU
;
Jun ZHENG
;
Ping WANG
;
Jiezhi WANG
- Publication Type:Journal Article
- From:
Chinese Journal of Tissue Engineering Research
2005;9(29):194-195
- CountryChina
- Language:Chinese
-
Abstract:
BACKGROUND:Single photon emission computed tomography (SPECT)measurement is capable of detecting very early cerebral circulatory disorders accurately and assessing the time-window and the possibility of reversible brain function after reperfusion at various post-ischemia time points.OBJECTIVE: To establish the swine model of ischemic stroke, to assess the time-window of reversible ischemia and to evaluate the significance of SPECT cerebral ischemia-perfusion imaging on predicting very early time window.DESIGN: Randomized, controlled and experimental study.SETTING: Neurological department of a municipal hospital.MATERIALS: From January to August 2002, it was completed at the Laboratory Animal Research Center of Qingdao Municipal Hospital. Twelve 4 months old domestic swine (Sus scrofa), males and females and weighing 8-10 kg, were selected and fed with conventional method.INTERVENTIONS: Twelve swine pigs were divided into block group and reperfusion group, 6 in each group. In all the pigs, common carotid artery in one lateral was blocked by a clamp. Animals in block group sacrificed at 2, 4, 5, 6, 8 and 10 hour respectively. In perfusion group, clamps were removed at 2, 4, 5, 6, 8 and 10 hour respectively, and then the animals were killed 24 hours later. Before sacrifice, all the animals underwent SPECT examination, regional cerebral blood flow (rCBF) measurement and CT scan. After sacrifice, 1 mm3 brain tissues were taken from each lobe and were stained by HE staining. Then light microscope and electron microscope were used to study the histological changes.MAIN OUTCOME MEASURES: SPECT and brain CT scan were used to investigate the cytological changes in brain tissues after various length of ischemiaRESULTS: Twelve swine pigs entered the statistical analysis procedure.By using light microscope and electron microscope, it was found that at 5 hour after operation, neurons in operational side were a little swelled, with swelled mitochondria, a mitochondria crests loss and a progressive plasma loss in a few neurons. While in those with clamps removed within 4 hours after turn off, brain tissue structures were mainly restored.CONCLUSION: SPECT is capable of detecting ischemic brain injury immediately. It is proved by histological evidence that a more-than-5-hour ischemia will cause irreversible changes in neurons.