99Tcm-HL91脑乏氧显像对脑血流低灌注区组织乏氧缺血细胞的评估价值

背景缺血性脑血管病患者病变区域内存在着存活的、但血流供应不足的脑组织,只要及时恢复血供,就可挽救.新型显像剂99Tcm-HL91脑乏氧显像可以显示脑血流灌注显像为低灌注区的乏氧、缺血但存活的这些脑组织.目的探讨新型乏氧显像剂99TcmHL91在缺血性脑血管病中的评估价值,为早期干预提供影像学依据.设计以患者和健康自愿者为研究对象,观察对比的验证性研究.单位一所大学医院的核医学科和一所省级医院的神经内科,核医学科.对象2000-03/2001-09在河北省人民医院随机选取门诊和住院的缺血性脑血管病患者18例及健康志愿者4例.方法对18例临床确诊为缺血性脑血管病患者和4例年龄匹配的健康志愿者进行脑乏氧断层显像,其中临床诊断脑梗死11例,短暂性脑缺血发作(TIA)5例,椎基底动脉供血不足2例,取标记好的99Tcm-HL91555～1110 MBq静脉推注,0～30 min内行脑乏氧断层显像,7例患者同时进行了CT或MRI检查,1例患者次日行99Tcm-ECD脑灌注断层显像,并对3种方法进行了对比研究.用视觉判定脑血流灌注显像低灌注区域内及周边部位放射性能变化,出现放射性浓聚者,为阳性,未出现放射性浓聚者为阴?介于两者中间者为临界(用计算机ROI技术与对照侧比较,两侧比值大于25%以上者诊断为阳性,小于者计入阴性组,本研究不设临界组).主要观察指标脑乏氧显像,T,RI,脑灌注显像结果.结果18例患者中脑乏氧显像阳性者5例,分别为脑梗死4例,椎基底动脉供血不足1例.11例同时行99Tcm-ECD脑血流灌注显像者中6例表现为局部脑血流灌注减低,T或MRI检查异常者9例,例健康志愿者未见异常显示.结论99Tcm-HL91脑乏氧显像诊断缺血性脑血管病的影响因素较多,但对脑血流灌注显像出现低灌注区时可以区分组织乏氧或坏死,对指导早期康复干预和预后评估有一定意义.

Value of 99Tcm-HL91 hypoxia imaging in identifying ischemic and hypoxic cells in law perfusion cerebral area

BACKGROUND: In the ischemic cerebral area there are viable tissues of low blood perfusion. Theses tissues can be rescued as long as blood supply is restored timely. As an imaging agent,99Tcm-HL91 can be used to demonstrate the viable cerebral tissues in hypoxic and ischemic area.OBJECTIVE: To investigate the value of 99Tcm-HL91 imaging in assessing ischemic stroke,in order to provide evidences for early intervention.DESIGN: An observational and controlled trial based on patients and healthy voluinteers.SETTING: A nuclear medicine department in a university and a neurological department and a nuclear medicine department in a provincial hospital.PARTICIPANTS: From March 2000 to September 2001,eighteen inpatients and outpatients suffering from ischemic cerebral diseases and 4 volunteers were enrolled in the study.METHODS: In the 18 patients,11 were clinically diagnosed as cerebral infarction,5 TIA,2 vertebrobasilar insufficiency. All the subjects underwent 99Tcm-HL91 cerebral hypoxia tomographic imaging. The labeled 99Tcm-HL91(555-1 110 MBq) was intravenously injected into the human body and imaging was conducted after 20 -30 minutes,17 patients underwent CT or MRI examination at the same time. Eleven patients underwent 99Tcm-ECD tomopraphic imaging on the next day. The results of the 3 examinations were compared with each other. The uptake in the inside and around-infarct areas was determined by direct visual observation on the images. Positive change was given by presence of increased uptake and negative by absence. The uptake change that could not be clearly defined as positive or negative was considered critical level. But the uptake on both hemispheres was compared with ROI technology. The change over 25% between hemispheres was set as positive and the other was negative. So there was no critical group in this study.MAIN OUTCOME MEASURES: The results of cerebral hypoxia imaging,CT,MRI and cerebral perfusion imaging.RESULTS: Among the 18 patients,5 were positive for hypoxia imaging(4infarction and 1 vertebrobasilar insufficiency). In the 99Tcm-ECD perfusion,6out of 11 patients manifested of regional decreased blood perfusion. Nine patients manifested of abnormal CT or MRI results. No abnormalities were detected in the 4 volunteers.CONCLUSION: Although 99Tcm-HL91 imaging for diagnosis of cerebral ischemic disease is affected by many factors,it can identify whether the ischemic tissue is hypoxic or necrotic when the perfusion imaging demonstrate low flow. So it helps in guiding rehabilitation intervention and foretelling prognosis.