Clinical Features And Prognosis Of Aneurysms At The Trifurcation Of The Middle Cerebral Artery

Background:As the most common cause of subarachnoid hemorrhage(SAH),intracranial aneurysms have a very high rate of disability and mortality,and once aneurysm ruptures are a great burden on the patient’s family and society,early detection and treatment of aneurysms is particularly important.Middle cerebral artery(MCA)is the second most common site of intracranial aneurysms,second only to the anterior in terms of incidence,and the MCA bifurcation is the best site for MCA aneurysm.The branching pattern of the MCA can be divided into bifurcation,trifurcation and tetrafurcation according to anatomy,and bifurcation is the main type.Trifurcation is a special type of middle cerebral artery,and the anatomy of trifurcation has been studied more at this stage,but little research about aneurysms has been performed.Objective:We conducted a statistical analysis of the epidemiology,morphology,surgical outcome,prognosis and complications of aneurysms at the trifurcation of the MCA,aiming to evaluate the clinical features and prognosis of aneurysms between the bifurcation and the trifurcation of the MCA and provide guidance for the future treatment of trifurcation type MCA bifurcation aneurysms.Method:A total of 159 cases of MCA bifurcation aneurysms treated with endovascular therapy were collected from August 2020 to August 2022 in the Department of Neurosurgery of the First Hospital of Jilin University,all of which were confirmed by digital subtraction angiography(DSA)and classified into MCA trifurcation aneurysms and MCA bifurcation aneurysms according to the bifurcation anatomical type.The epidemiology,morphology,surgical results,prognosis and complications of the cases were retrospectively analyzed to explore the clinical features and prognosis of aneurysms at the MCA trifurcation.Outcome:A total of 154 patients in the included studies,contributing 159 MCA bifurcation aneurysms,including 121(76.1%)in the MCA bifurcation aneurysm group and 38(23.9%)in the MCA trifurcation aneurysm group.Sex,age,history of hypertension,previous history of SAH and whether there was a combination of aneurysm rupture caused by SAH were statistically analyzed,and the results confirmed that there was no significant difference between the two groups.The morphological parameters of the two groups(including aneurysm size,aneurysm morphology,aneurysm neck width,M1 length,aspect ratio,size ratio,M1/M2,M2 branch angle and inflow angle)were statistically analyzed,and the results showed that the aneurysm size,aneurysm morphology,aneurysm neck width,M1 length,aspect ratio,size ratio and inflow of the two groups of data displayed no statistically significant difference in angle.The average angle of the M2 branch in the aneurysm group at the bifurcation of the MCA was 160.71±28.92;the average value of M1/M2 was 0.57±0.12;the average angle of the M2 branch in the aneurysm group at the trifurcation of the MCA was 205.42±23.65,and the average value of M1/M2 was 0.45±0.10.Of the 118 patients in the bifurcation aneurysm group of the MCA,113(95.8%)were discharged in good condition,2(1.7%)were in poor condition,and 3(2.5%)died.Among the 36 patients in the aneurysm group at the trifurcation of the MCA,35(97.2%)were discharged well,1(2.8%)in poor condition,and there were no deaths.The prognosis of the two groups was statistically analyzed,and the results showed no significant difference in prognosis between the two groups(P=0.804).Conclusion:(1)There was no significant difference in the morphological parameters of the aneurysm at the bifurcation of the MCA and the aneurysm at the trifurcation of the MCA except for the angle of M2 and M1/M2;(2)The utilization rate of stent at aneurysm of the MCA trifurcation is high,and interventional surgical treatment is safe and reliable.(3)There is no difference in the surgical method and prognosis between the aneurysm at the bifurcation of the MCA and the aneurysm at the trifurcation of the MCA.No special treatment is required for the treatment of trifurcation MCA aneurysm compared with MCA bifurcation aneurysm.(4)Aneurysms at the MCA trifurcation are mainly wide carotid aneurysms and irregular aneurysms,and these aneurysms should be evaluated and treated timely.