A relative study on cerebral hemodynamic changes after unilateral superficial temporal artery-middle cerebral artery(STA-MCA)bypass surgery / 中国脑血管病杂志

ABSTRACT

Objective To investigate the hemodynamic,cerebral perfusion and neurological function changes between unilateral symptomatic internal carotid artery occlusion(SICAO)and symptomatic middle cerebral artery occlusion(SMCAO)after superfical temporal artery-middle cerebral artery(STA-MCA)bypass surgery as well as the correlation between relative peak volume of blood flow(rPVOL)in STA measured by carotid Doppler ultrasonography(CDU)and relative cerebral blood flow(rCBF)by CT perfusion(CTP).Methods Retrospective analysis of 112 patients who diagnosed with unilateral SICAO or SMCAO through DSA and/or CT angiography(CTA)and underwent superficial temporal artery-middle cerebral artery(STA-MCA)bypass in the Department of Neurosurgery at First Affiliated Hospital of Soochow University from March 2019 to June 2022.The patients were divided into SICAO group(50 cases)and SMCAO group(62 cases)and followed up for 360 days.General clinical and imaging data of patients in two groups were collected.General clinical information included age,gender,clinical manifestations(stroke,transient ischemic attack[TIA]),hypertension,diabetes,smoking history,blood biochemical indicators(total cholesterol,triacylglycerol,low-density lipoprotein cholesterol,high-density lipoprotein cholesterol,high-sensitivity C-reactive protein),National Institute of Health stroke scale(NIHSS)scores at admission and 7 days after surgery,and modified Rankin Scale(mRS)scores at admission and 7,180 and 360 days after surgery(mRS scores 2 as good prognosis,＞2 as poor prognosis).Imaging data included hemodynamic parameters(STA diameter[D],resistance index[RI],time-averaged-mean velocity[TAMV],and time-average-peak flow velocity[TAPV])evaluated by CDU within 7 days before and 7,30,180 and 360 days after STA-MCA bypass,as well as CTP parameters(rCBF,relative cerebral blood volume[rCBV],relative mean transit time[rMTT]and relative time to peak[rTTP])of the head region of interest(ROI)before and 7,180 and 360 days after surgery.Patients were observed 1 year after surgery through outpatient or telephone follow-up to determine if they have experienced recurrent stroke(TIA,cerebral infarction,etc.)and other postoperative complications(subdural hematoma,cerebral hemorrhage,etc.).DSA imaging was also performed to determine the patency of vascular anastomosis of patients in SICAO and SMCAO groups.STA hemodynamic parameters,head CTP parameters,NIHSS scores,and mRS scores at different time points before and after STA-MCA bypass surgery were compared between SICAO and SMCAO groups correspondingly;STA hemodynamic parameters,head CTP parameters,and mRS scores were pairwise compared between different time points within each group.A correlation analysis was conducted between rCBF and rPVOL in STA which was measured by CTP and CDU accordingly in the SICAO and SMCAO groups to further determine the consistency of the blood flow through STA and intracranial cerebral blood flow.Results(1)There was no statistically significant difference in general clinical data between the two groups(all P＞0.05).(2)Comparison of STA hemodynamic parametersD,TAMV,and TAPV of both groups significantly increased at 7,30,180,and 360 days after surgery(all P＜0.05)compared with preoperative,and reaching their peak at 7 days after surgery,and there was no statistically significant difference in D,TAMV,and TAPV among 30,180,and 360days after surgery(all P＞0.05).There was no statistically significant difference in D,TAMV,or TAPV between the two groups at each time point(DF=2.286,TAMVF=0.180,TAPVWald x=1.709;all P＞0.05).RI of the two groups was significantly reduced at 7,30,180,and 360 days after surgery(all P＜0.05)compared with preoperative,and there was no statistically difference in RI among 7,30,180,and 360 days after surgery(all P＞0.05).There was also no statistically difference in RI between the two groups at each time point(Wald x2=0.788,P＞0.05).(3)Comparison of CTP parameters between two groupscompared to preoperative,rCBF and rCBV in the SICAO group and SMCAO group increased at 7,180,and 360 days after surgery(all P＜0.05),there was no statistically difference in CTP parameters within the two groups at different time points(Wald x2 was 0.177,2.954,respectively,all P＞0.05),and the rMTT and rTTP of both groups decreased at 7,180,and 360 days after surgery(all P＜0.05),there was no significant difference in rMTT and rTTP between the two groups at different time points(Waldx2 was 2.157,1.706,respectively,all P＞0.05),and there was no statistically difference in the parameters of each postoperative time point within each group(all P＞0.05).(4)Comparison of vascular patency between two groups1 year DSA showed that 91.1％(102/112)of patients were patent,with 92.0％(46/50)in the SICAO group and 90.3％(56/62)in the SMCAO group.There was no statistically difference between the two groups(x2=0.001,P＞0.05).The STA hemodynamics and intracranial CTP parameters of the two groups of patients with patent anastomosis were significantly improved compared to preoperative.A total of 10 patients were non-patent by 1 year DSA,including 4 cases in the SICAO group and 6 cases in the SMCAO group.In 1 non-patent SICAO patient and 3 non-patent SMCAO patients,the STA hemodynamic parameters evaluated by CDU 180 days and 360 days after surgery also showed corresponding improvement compared to preoperative,with an increase in TAMV and TAPV,and a decrease in RI.(5)Comparison of neurological improvement between the two groupscompared with preoperative,the mRS scores of the SICAO group and the SMCAO group significantly decreased at 7,180,and 360days postoperatively(all P＜0.05);there was no statistically difference in the mRS scores within each group at 7,180,and 360 days after surgery(P＞0.05).There was no statistically difference in mRS scores between the two groups at different time points including admission and 7,180 and 360 days after surgery(Wald x2=0.006,P＞0.05).The NIHSS scores of the SICAO group and the SMCAO group decreased at 7 days after surgery compared to admission(Z was 21.040,-5.183,respectively,all P＜0.01),and there was no statistically difference in NIHSS scores between the two groups at admission and 7 days after surgery(both P＞0.05).(6)Spearman rank correlation analysis showed that rPVOL and rCBF were highly positively correlated in the SICAO group(r=0.865,P＜0.01)and in the SMCAO group(r=0.864,P＜0.01).Conclusions Unilateral STA-MCA bypass can improve cerebral perfusion and neurological function in patients with SICAO and SMCAO,and there is no statistical difference between the two groups of patients.The rPVOL measured by CDU was highly correlated with the rCBF in patients after STA-MCA bypass surgery.