目的：本研究试图通过测量梗死区引流静脉的相位差，并结合局部血流动力学的改变，探讨SWI上引流静脉信号变化的可能机制以及其对急性脑梗死患者的临床应用价值。方法：回顾性分析急性缺血性脑梗死患者20例，年龄47~82岁，平均61岁；发病时间7~48小时，平均28小时。行磁敏感加权成像（SWI）、动态磁敏感对比增强灌注加权成像（DSC-PWI）扫描，测量梗死区与对侧相应区域静脉血管的相位差（分别用Δφ病灶和Δφ对侧表示），测量梗死区与对侧相应区域的rCBF值、rrCBF值及rCBV值，测量脑梗死患者NIHSS评分。结果：①梗死区静脉相位差Δφ病灶=547.0±155.7spin，对侧静脉相位差Δφ对侧=282.65±96.67spin，梗死区静脉相位差显著大于健侧（t=5.861，P<0.001）；②梗死区rCBF值小于健侧（t=-8.978，P<0.001），梗死区rCBV值亦小于健侧（P=0.008）；③Δφ病灶与NIHSS评分呈显著正相关（r=0.933，P＜0.001），Δφ病灶与rrCBF呈显著正相关（r=0.681，P=0.001），rrCBF与NIHSS评分呈正相关（r=0.645，P=0.002）。结论：SWI脑梗死引流静脉相位差所反映的氧代谢异常与CBF的相关性符合脑血流-代谢耦联机制，可作为临床评价急性梗死患者病情程度的可靠指标。
Abstract
Objective: To explore the possible causes and clinical values of the signal and phase variation of the draining veins in patients with acute cerebral infarction, by measuring the phase differences of the draining veins combined with the local hemodynamic changes. Methods: Twenty patients(aged 47~82 years, mean age 61 years; time of onset 7~48 hours, mean time 28 hours) with acute ischemic cerebral infarction were analyzed retrospectively. The scanning sequences included susceptibility weighted imaging(SWI) and dynamic susceptibility contrast-enhanced perfusion-weighted imaging(DSC-PWI). The phase differences of the veins in the infarct and contralateral areas(respectively denoted by Δφlesion and Δφnormal) were measured. The rCBF values, rrCBF values and rCBV values in the infarct and contralateral areas were measured. NIHSS scores were recorded. Results: ①The phase difference of affected side Δφlesion value=547.0±155.7(spin), the contralateral phase difference Δφnormal value=282.65±96.67(spin), Δφlesion was significantly greater than Δφnormal(t=5.861, P<0.001); ②rCBF values in the infarct area were significantly lower than that of the contralateral area(t=-8.978, P<0.001), and rCBV values in the infarct area were also lower than that of the contralateral area(P=0.008); ③There was significant positive correlation between the Δφlesion values and NIHSS scores(r=0.933, P＜0.001), and there was significant positive correlation between the Δφlesion values and rrCBF values(r=0.681, P=0.001), rrCBF values had positive correlation with NIHSS scores(r=0.645, P=0.002). Conclusion: The correlation between the phase differences in the infarct area that reflected the oxygen metabolic abnormalities and CBF were consistent with the cerebral flow-metabolism coupling mechanism. The phase differences of the veins in the infarct area could be used as a reliable indicator to evaluate the clinical severity of the patients with acute infarction.
关键词
脑梗塞 /
磁共振成像
Key words
Brain infarction /
Magnetic resonance imaging
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