体感诱发电位和经颅多普勒超声联合监测在颈动脉内膜切除术中的应用

The application of somatosensory evoked potential combined with transcranial Doppler ultrasound monitoring in carotid endarterectomy

目的探讨体感诱发电位(SEP)和经颅多普勒超声(TCD)联合监测方法在颈动脉内膜切除术(CEA)中的应用价值。方法回顾性纳入2015年1月至2018年1月于承德市中心医院神经外科行CEA的50例颈动脉狭窄患者,术中均应用SEP和TCD联合监测,记录SEP的N20波幅变化,以及TCD监测显示的大脑中动脉血流速度的变化,从而决定是否实施转流术,并判断开放的颈动脉是否出现再狭窄以及有无脑高灌注情况。术中记录两种监测方法的监测数据并进行对比分析。结果术中SEP监测结果显示2例达到转流标准,术中实施转流术;TCD监测结果显示8例达到转流标准(包括SEP监测达到转流标准的2例)。应用SEP(4.0%,2/50)和TCD(16.0%,8/50)监测达到转流标准比率的差异有统计学意义(χ^2=4.000,P=0.046)。2例行两种监测均未达到转流标准的患者术中开放阻断的颈动脉后,TCD监测结果提示再次出现重度狭窄或闭塞,而SEP监测无阳性发现;另2例行两种监测均未达到转流标准的患者开放阻断的颈动脉后,TCD监测结果提示高灌注,SEP亦无阳性发现。50例患者CEA术后30d内无一例发生脑梗死、脑出血、过度灌注以及死亡,复查CT血管成像显示所有患者的颈动脉狭窄解除。结论SEP和TCD联合监测在CEA术中具有较高的临床应用价值。前者可能在判断术中转流方面更有优势,后者在术中开放颈动脉后判断颈动脉再次出现重度狭窄或高灌注方面可能更有价值。

Objective To explore the application value of combined monitoring of somatosensory evoked potential (SEP) and transcranial Doppler ultrasound (TCD) in carotid endarterectomy (CEA). Methods We retrospectively enrolled 50 patients with carotid stenosis who underwent CEA at Department of Neurosurgery, Chengde Central Hospital from January 2015 to January 2018. SEP and TCD were used in combination to record changes in N20 amplitude of SEP and blood flow velocity in the middle cerebral artery (MCA) by TCD monitoring. Whether or not to perform a bypass procedure was decided based on the monitoring results which was also used to judge whether the open carotid artery developed restenosis and assess the high brain perfusion. The data of the two monitoring methods were recorded during the operation and comparative analysis was performed. Results Intraoperative SEP monitoring results showed that 2 cases met the standard of bypass and then underwent intraoperative transferring. TCD monitoring showed that 8 cases reached the standard of bypass and included the above-mentioned 2 cases. The difference in the rate of conversion to standard was statistically significant using SEP (4.0%, 2/50) and TCD (16.0%, 8/50)(χ^2=4.000, P=0.046). In those 2 patients whose monitoring results showed that they did not meet the standard of bypass, after opening blocked carotid artery in the operation, TCD monitoring showed severe restenosis or reocclusion, and the thrombus was opened again during the operation. However, there was no positive findings in SEP monitoring during this process. In 2 case with open-blocking carotid artery, whose data in both monitoring showed that they did not meet the standard of bypass, high perfusion was revealed by TCD, and no positive findings were found in SEP monitoring. There was no cerebral infarction, cerebral hemorrhage, hyperperfusion or death in 50 patients within 30 days after CEA. CT angiography results showed no carotid stenosis in this series. Conclusions The combined monitoring of SEP and TCD seems to have a high clinical value in CEA. The former may be more advantageous in making choice of intraoperative bypass. The latter may be more valuable in detection of severe restenosis or recurrent hyperperfusion after opening the carotid artery.