Endovascular Treatment Of Posterior Circulation Aneurysm And Related Anatomy

Objective1,To summarize the characteristics of morphology,distribution and clinical presentation of aneurysms located in the posterior circulation;2,To evaluate the safety and efficacy of endovascular treatment in the posterior circulation aneurysms,which have different morphologies and different locations;3,To investigate the morphology,course and supply of the posterior circulation and provide anatomic data of the posterior circulation for endovascular treatment of the posterior circulation aneurysms and its related clinical presentation.Materials and methods1,From November 1996 to December 2006,128 cases with posterior circulation aneurysms were admitted to our institution,and its clinical presentation,location and morphology were analyzed retrospectively;2,One hundred and three patients with 104 aneurysms were treated by the different endovascular therapeutics,which included only microcoils occlusion(21 aneurysms),stent-assisted coiling(16 aneurysms),only stent implantation(18 aneurysms),Remodeling technique(7 aneurysms) and parent artery occlusion(39 aneurysms);3,Morphology,course and distribution of posterior circulation arteries were studied and measured on 7 adult head specimens.Results1,Clinical presentation of the posterior circulation aneurysm was mostly subarachnoid hemorrhage(SAH) and cerebral ischemia;there were more saccularanenrysms(43.61%) and fusiform aneurysms(45.11%) than dissecting aneurysms(11.28%) in aneurismal modality;aneurismal locations were mostly seen in the basilar artery(BA,42.86%),especially in its tip(45.61%),next to the vertebral artery(VA,35.34%),posterior cerebral artery(PCA,18.05%),superior cerebellar artery(1.50%) and posterior inferior cerebelar artery(2.26%),respectively;large aneurysms(diameter of aneurismal body more than 7mm,77.44%) were frequently seen;2,Among 103 cases received endovascular treatment,34 cases were achieved complete occlusion,28 cases near-complete occlusion and 40 cases imcomplete occlusion after immediate evaluation,rate of technical success represented 97.1%,three treatment failures occurred secondary to unfavorable anatomy.Nine patients experienced complications and 4 patients died,the morbidity and mortality were 8.74%and 3.88%respectively;follow-up was achieved in 42 cases from 2 to 12 months.Six patients experienced recurrence(one case was complete occlusion,the other incomplete occlusion),represented 5.83%.Conclusions1,Endovascular treatment of the posterior circulation aneurysm is safe and effective, its morbidity and mortality is lower;2,Parent artery occlusion is a practical method to the treatment of the posterior circulation aneurysm,especially for large and giant aneurysms located in the P2 segment of PCA and VA,and have lower morbidity,but for the P1 segment of PCA and BA,the operation is avoided as far as possible;3,For fusiform,dissecting and wide-neck saccular anenrysms located in the posterior circulation,stent-assisted coiling is an effective method;4,Applied anatomy of the posterior circulation contributes to choose the method of endovascular therapy and find promptly related presentation,and more improve the efficacy of the posterior circulation aneurysm.