Anterior communicating artery aneurysm associated with duplicated hypoplastic right A1 segment

Variations of the anterior cerebral artery(ACA)-anterior communicating artery(ACo A) complex are commonly observed when associated with a symptomatic intracranial aneurysm. We report an asymptomatic ACo A aneurysm associated with duplicated hypoplastic A1 segment of the right ACA, observed in a 70-year-old female cadaver. Furthermore, the aneurysm, practically substituting the ACo A, caused a remarkable depression on the internal surface of the right frontal lobe, anterior to the optic chiasm. Aneurysms and other anomalies of the ACA and ACo A are common and their microvascular surgical management requires sound knowledge of the normal and variant vascular anatomy. Persistence of some embryonic vessels that normally disappear, disappearance of vessels that would normally persist or sprouting of new vessels due to hemodynamic and genetic factors are the usual causes for such anomalies. The high incidence of coexisting vascular anomalies and aneurysm suggests that such abnormalities predispose to aneurysm formation due to changes in the regional blood flow. A1 segment duplication has been reported to occur in 4% of subjects in cadaveric studies and in up to 0.5%-9.7% of cases of ACo A aneurysm surgery. Angiographic hypoplasias and aplasias of the A1 seg-ment have been also correlated with ACo A aneurysm patients.

Influence of Clip Locations on Intraaneurysmal Flow Dynamics in Patient-specific Anterior Communicating Aneurysm Models with Different Aneurysmal Angle

To improve aneurysm treatment,this study examined the influence of clip locations on hemodynamic factors in patient-specific anterior communicating artery(ACoA)aneurysms with different aneurysmal angle.We proposed a simplified classification of ACoA aneurysms using aneurysmal angle,defined by the angle of pivot of the aneurysmal dome and the virtual two-dimensional plane created by both proximal A2 segments of anterior cerebral artery(ACA).ACoA aneurysms with three different aneurysmal angles,which are 15°,80°and 120°,were analyzed in our study.In this work,we obtained hemodynamics before and after clipping surgery with three clip locations based on clinical clipping strategies in three ACoA aneurysms with different aneurysm angles.Results showed that local high pressure occurs at impingement region of the ACoA aneurysm before clipping and new impingement region close to the clipping location after clipping treatment.For clipping the aneurysm with aneurysmal angle 15°and a wide neck,wall shear stress(WSS)distribution is more uniform when the clipping angle of two clips close to 180°comparing with other two angles.In addition,for clipping the aneurysm with aneurysmal angle 80°and 120°,local high pressure appears on new impingement region and high WSS distributes around the clipping location when the clip plane is normal to the direction of inflow of aneurysm from the dominance of A1 segment of ACA.Hence,we should avoid the impingement of inflow from the A1 segment and choose a favorable clipping location for the fastness of clip.The results of our study could preoperatively give a useful information to the decision of surgical plan.

颅内-颅内血管搭桥侧侧吻合术治疗复杂颅内动脉瘤长期疗效观察

目的 探讨颅内-颅内血管搭桥侧侧吻合术治疗复杂颅内动脉瘤的长期疗效。方法 纳入2015年1月至2023年12月由中国医科大学附属第一医院神经外科同一术者实施颅内-颅内血管搭桥侧侧吻合术的5例复杂颅内动脉瘤患者,2例累及大脑前动脉A2段,3例累及大脑中动脉M2段。术中采用吲哚菁绿荧光血管造影术(ICGA)、术后采用CTA或DSA评估动脉瘤闭塞和血流重建情况;术后1周、3个月和末次随访时采用改良Rankin量表(mRS)评估神经功能预后;术后第1天、1周和3个月行头部CT和(或)MRI检查,评估是否发生出血性或缺血性并发症。结果 本组5例复杂颅内动脉瘤均孤立确切,2例行A3-A3侧侧吻合术;3例行M2-M2侧侧吻合术,其中1例在M2-M2侧侧吻合术基础上获取桡动脉(RA)作为桥血管,联合M1-RA-M2嵌入桥接式血管搭桥术。术中经ICGA证实,5例侧侧吻合口和1例M1-RA-M2桥血管均通畅。术后随访时间为23(14,71)个月,5例术后1周和术后3个月CTA或DSA检查、3例术后9~12个月DSA检查均未见动脉瘤显影,5例侧侧吻合口和1例M1-RA-M2桥血管均通畅。术后1周mRS评分较术前升高0~3分(1例手术前后均为4分、1例增加2分、1例增加3分),2例未破裂患者术后1周mRS评分无变化(均为1分);术后3个月mRS评分均下降(0分2例、2分1例、3分2例);末次随访时1例失访,余4例mRS评分进一步下降(0分2例、1分1例、2分1例)。术后无脑出血或脑缺血事件发生。结论 颅内-颅内血管搭桥侧侧吻合术的短期和长期通畅性良好,长期疗效稳定,是复杂颅内动脉瘤手术治疗的可靠技术。

Factors determining the side of approach for clipping ruptured anterior communicating artery aneurysm via supraorbital eyebrow keyhole approach

Purpose:The purpose of this study was to review the microsurgical anatomy and clipping of ruptured anterior communicating artery(AComA)aneurysms and to plan and avoid complications before operation.Methods:A total of 523 cases of cerebral aneurysms admitted to the neurosurgery department of the Third Affiliated Hospital of Sun Yat-Sen University from September 2010 to October 2018 were analyzed retrospectively.Among them,85 patients had ruptured AComA aneurysms.This study was limited to 85 of these cases,whose satisfactory preoperative angiographic diagnostic films can be retrieved from the hospital database system because of the need for detailed review.Results:We performed supraorbital eyebrow keyhole approach(SOEK)craniotomy in 85 patients to clip 85 AComA aneurysms,in the setting of subarachnoid hemorrhage(SAH).Patients’mean age was(52.69±9.94)years(range,28e78 years).The proportions of small,medium and large aneurysms were 83.5%,15.3%,and 1.2%,respectively.The average size of the aneurysms was(5.07±2.36)mm.There were 77.8% of patients with inferior aneurysms and 81.3% of patients with superior aneurysms achieved good results.There was a significant correlation between A1 dominance and operation method(p<0.001).There was no significant relationship between surgical approach and aneurysm projection or A2 plane(p=0.157&p=0.318).Conclusion:Regardless of whether the A2 plane is open or closed,the A1 dominant side is still a better choice for accessing AComA aneurysms to avoid dangerous premature bleeding.

Endoscopic anatomical study on anterior communicating artery aneurysm surgery by endonasal transphenoidal approach

Background:Endonasal transphenoidal approach by neuroendoscopy has its own advantage,such as direct access invasive,better visualization of the anterior communicating artery aneurysm and so on.The study is to provide anatomical knowledge for anterior communicating artery aneurysm surgery by endonasal transphenoidal approach with neuroendoscopy.Materials:Take 10 skull base specimens,observe and measure the anatomical structures around anterior communicating artery.Take 10 cadaveric heads,simulate the anterior communicating artery aneurysm surgery with neuroendoscopy by endonasal transphenoidal approach.Find the natural opening of sphenoid sinus,then open the skull base,expand bone window in anterior skull base.After that,cut off the dura,find the optic nerve,optic chiasm,cisterna lamina terminalis,anterior cerebral artery,a portion of frontal lobe,anterior communicating artery complex and its important branches,such as heubner artery,hypothalamic artery,orbitofrontal artery and so on.Lift up anterior communicating artery complex and seperate arachnoid in cisterna lamina terminalis,the lamina terminalis is exposed.Block bilateral A1 of anterior cerebral artery with aneurysm clip,the anterior communicating artery complex and its important branches are in view,so we can clip anterior communicating artery aneurysm safely.Results:Anterior communicating artery aneurysm surgery can be finished with neuroendoscopy by endonasal transphenoidal approach.The vital structures can be clearly observed with neuroendoscopy.The rhombus anatomic region formed by bilateral olfactory nerve and optic nerve is a safe surgical area.According to the calculation,the safe surgical area is about 161.48 ± 12.78 mm2.Measure the distance between the important anatomic structures in the rhombus anatomic region.By means of SPSS 17 Statistical analysis softvvare,the measuring distance is expressed with (x ± S)mm.Conclusion:The anterior communicating aneurysm surgery by endonasal transphenoidal approach with neuroendoscopy has its own advantage,such as direct access,minimally invasive,less bleeding,light pain,quick recovery,better visualization of the anterior communicating artery aneurysm and so on.This operation approach needs further study and exploration to clinical application,in order to become a mature approach of anterior communicating artery aneurysm surgery.

Terson Syndrome:A Case of Anterior Communicating Artery Aneurysm Rupture with Spontaneous Subarachnoid Hemorrhage

Terson syndrome is manifested as retinal and vitreous hemorrhage with aneurysmal subarachnoid hemorrhage(SAH),and is associated with the severity,high mortality and poor prognosis of aneurysmal SAH.Severe Terson syndrome can lead to vision loss or even permanent blindness.The prevalence of Terson syndrome is 2.6%-50%on a global scale;however,it is often misdiagnosed due to the lack of routine ophthalmologic examination and the early comorbidities of cognitive disorder,laloplegia and coma.Herein,we report a 29-year-old male patient who suffered from aneurysmal SAH with Terson syndrome in department of neurosurgery,the First Affiliated Hospital,Zhejiang University,School of Medicine,to highlight the importance of early diagnosis and treatment of Terson syndrome.

大脑前动脉搭桥术在复杂前交通动脉瘤中的应用

大脑前动脉搭桥术是治疗前交通动脉瘤的重要方法,根治动脉瘤的同时应保证大脑前动脉灌注区的血供。大脑前动脉搭桥术旨在重建前交通动脉功能,情况复杂,手术难度大。在血运结构上,前交通动脉作为Willis环的前部枢纽,远离颞浅动脉和颈外动脉等常规供体动脉,血管重建方案在受体动脉方面需兼顾双侧血管,与血管搭桥术密切相关的前交通动脉复合体存在诸多变异;在手术操作上,前交通动脉位置深在,术野狭小,属于深部搭桥,同时因额叶的遮挡,供血区和受血区同时显露受到限制,动脉瘤体较大时更增加显露难度。基于上述血流动力学和血管结构的复杂性,以及随着手术入路向颅底扩展形成的各种颅内搭桥新路径,本文对大脑前动脉搭桥术在前交通动脉瘤中的特点、血管重建方案的创新设计和手术入路的选择进行综述。