CT灌注成像在蛛网膜下腔出血后脑血管痉挛诊断中的应用

Application of CT perfusion imaging in cerebral vasospasm caused by intracranial subarachnoid hemorrage

目的 CT灌注成像技术对颅内动脉瘤破裂蛛网膜下腔出血(SAH)所产生的脑血管痉挛(CVS)的诊断价值。方法 30例动脉瘤破裂SAH患者均在出血后急诊DSA造影和血管内栓塞治疗。分别于出血后3、7、10、142、1d行CT灌注成像(CTPI)检查。选择6例正常志愿者的脑CTPI数据作为对照。结果 30例患者中,10例出现脑缺血症状。与对照组比较,无脑缺血症状组脑血流量(CBF)值出血后第14天明显降低,造影剂平均通过时间(MTT)值于出血后第10、14天明显延长(P<0.05)。脑缺血症状组MTT值第7天开始即升高,且至21 d仍然高于对照组(P<0.05)。感兴趣区CBF值第10天开始降低,持续至第14天,脑血容量(CBV)值第14天起开始降低,至21 d数值仍低于对照组(P<0.05)。结论 MTT是判断迟发性脑血管痉挛比较敏感的指标。CBF对于检测脑组织异常灌注具有较高的敏感性和稳定性。CBV显著下降是预测不可逆性脑梗死的较为准确的指标。

Objective To investigate the significance of computed tomography perfusion imaging（CTPI） in diagnosing the cerebral vasospasm（CVS） caused by intracranial subarachnoid hemorrage（SAH）.Methods Thirty patients with intracranial aneurysms received DSA and embolotherapy immediately after rupture.The CTPI was performed on the 3rd,7th,10th,14th and 21st day after operation.Six healthy people（group B） were taken as the controls.Results Of 30 patients,10 patients（group A1） had symptoms of cerebral ischemia.Compared to group B,cerebral blood flow（CBF） was significantly decreased on the 14th day and the mean time of passing（MTT） was significantly longer on the 10th and 14th day（P0.05） in 20 cases without symptoms of cerebral ischemia（group A2）.MTT in group A1 was longer on the 7th day,which was still longer than that on the 21st day in group B（P0.05）.CBF in ROI area began to decrease on the 10th to 14th day,cerebral blood volume（CBV） began to decrease on the 14th day,which was still lower than the controls on the 21st day（P0.05）.Conclusion The MTT is the sensitive index for evaluating later onset CVS after intracranial SAH.CBF as an indicator to reflect abnormal perfusion condition of the brain tissues is stable and sensitive.The significantly decrease of CBV is a comparatively precise index to predict the irreversibility of cerebral infraction.