Clinical Study Of Clipping Bilateral Anterior Circulation Cerebral Aneurysms Via Unilateral Keyhole Approach

Objective:Bilateral anterior circulation cerebral aneurysms are common in clinical practice.At present,there is no consensus of the surgical method about bilateral anterior circulation cerebral aneurysms.This article used to analyze the feasibility,safety,and effectiveness of this surgical method through a retrospective research,in the hope of making a clinical summary about it.Methods:There were a retrospective study of 45 surgical cases of bilateral anterior circulation cerebral aneurysms: 1.By collecting patient general information and preoperative imaging materials,measuring the position,orientation,size,and distance from the predicted bone hole to the neck of contralateral aneurysm,etc.,we analyzed the influence of various factors on the exposure of aneurysm,and analyzed the feasibility of this surgery method;2.We collected clinical information and the occurrence of postoperative complications,and analyzed related risk factors.Then we Evaluate the safety of this surgery method;3.Through two follow-ups before and after discharge,we analyzed the risk factors of the residual rate of aneurysm and the related factors of longterm prognosis.Finally,We evaluated the effectiveness of this surgery method.Results: 1.Among the 45 cases of bilateral anterior circulation cerebral aneurysms,30 had successfully clipped bilateral anterior circulation aneurysms through a unilateral keyhole approach,and 15 had only clipped unilateral aneurysms.The average age was56.49±9.05 years old.12 were male(26.67%)and 33 were female(73.33%).Preoperative imaging data revealed a total of 48 contralateral aneurysms,all were saccular aneurysms,including 13 internal carotid artery aneurysms(27.08%),3 anterior cerebral artery aneurysms(6.25%),including 13 middle cerebral artery(MCA)aneurysms(35.42%),15 posterior communicating artery(ACA)aneurysms(31.25%),and seven aneurysms(14.58%)toward the inside,3(6.25%)towards the front,13(27.08%)towards the posterior side,7(14.58%)towards the upper side,6(12.5%)towards the lower side,and12(25%)toward the outside.The average distance from the predicted bone hole to the contralateral aneurysm neck was 6.94±0.95 cm.The maximum diameter and orientation of the aneurysm were the influencing factors for the exposure of the contralateral anterior circulation aneurysm(P<0.05).The maximum diameter of the aneurysm was negatively correlated with the degree of exposure,and the inner aneurysm was more likely to be exposed.The influence of age,gender,distance from bone hole to the contralateral aneurysm neck and aneurysm location on the degree of exposure was not statistically significant.2.Among the 30 successfully clipping contralateral aneurysms cases,5(16.67%)had neurological complications related to the contralateral clamping of the aneurysm.There were 5 cases with cranial nerves and intracranial vessels covering the neck of aneurysm when the contralateral aneurysm was clipped,and this factor was the risk factor for postoperative complications(P<0.05).3.Two contralateral aneurysms appeared residual(4.16%)after clipping.The 1 year follow-up results showed that the long-term prognosis was good in 27 cases(90.00%),and poor in 3(10.00%).There was no significant difference in the prognosis of this operation compared with the unilateral approach for clipping the ipsilateral aneurysm.Conclusion: 1.clipping bilateral anterior circulation cerebral aneurysms via unilateral keyhole approach is safe and effective when the contralateral aneurysms are at the maximum diameter of 3-9mm,located in the inner carotid artery(ICA)clinoid segment(toward the inside),the eye segment(toward the upper side and inside)and the ICA bifurcation(toward the posterior side),A1 segment(toward the front,inner,and lower sides),M1 segment(toward the inner,lower,anterior and posterior sides)and the posterior communicating artery(PCo A)(toward the inner side).The size and orientation of the aneurysm are the factors that influence the exposure of the contralateral aneurysm neck,while factors such as age,gender and distance from bone hole to the contralateral aneurysm neck aren’t.The contralateral aneurysms with the largest diameter ≥10mm,located in the inner carotid artery clinoid segment(toward the inferior and posterior side)and ocular segment(toward the posterior side)are not feasible for the application of this operation.2.We should avoid damaging the optic nerve,oculomotor nerve and surrounding perforating branches when using this surgery to clip aneurysms in the contralateral ICA eye segment and the starting part of PCo A.And should also observe the back of aneurysm body and avoid damage to the surrounding lenticular artery to avoid leading related neurological complications when clipping the contralateral M1 bifurcation aneurysm.3.The relationship between cerebral aneurysm and skeletal structure can be analyzed based on CTA image before operation,so as to evaluate the feasibility of this operation.If there are cranial nerves and intracranial vessels covering the neck of the contralateral aneurysm before or during the operation,we should abandon this surgical method and avoid unnecessary exploration during the operation.