Kanemoto Yukihide, Michiwaki Yuhei, Maeda Kazushi, Kawano Yosuke, Maehara Naoki, Nagaoka Shintaro, Gi Hidefuku
Department of Neurosurgery, Baba Memorial Hospital, Sakai City, Osaka, Japan.
Department of Neurosurgery, Baba Memorial Hospital, Sakai City, Osaka, Japan.
World Neurosurg. 2020 Jul;139:e45-e51. doi: 10.1016/j.wneu.2020.03.037. Epub 2020 Mar 16.
True posterior inferior cerebellar artery (PICA) aneurysms outside the vertebral artery-PICA region are rare, with approximately 30 cases reported in just a few papers; no treatment paradigm has been advocated. The objective of this study was to present detailed clinical features and outcomes for several treatments for true PICA aneurysms and suggest an algorithm for treatment strategies.
We retrospectively analyzed outcomes of patients treated for PICA aneurysms with microsurgical and endovascular treatments. We also investigated the influence of several factors on the modified Rankin Scale score.
Cases with PICA aneurysms (n = 36) outside the vertebral artery-PICA region were identified angiographically. Aneurysm locations included anterior medullary (n = 7), lateral medullary (n = 10), tonsillomedullary (n = 4), telovelotonsillar (n = 12), and cortical (n = 3) segments of the PICA. Aneurysm morphology was as follows: dissecting: 22; fusiform: 6; and saccular: 8. On multivariate analysis, age (P = 0.028) and lack of vermian infarction (P =0.037) were associated with a significantly better prognosis. Prognosis was not significantly different for the 5 aneurysm locations and among the 4 treatment groups: clipping/coiling, trapping/parent artery occlusion, trapping/parent artery occlusion + bypass, and observation including external ventricular drainage.
This study suggests that factors associated with significantly better prognosis include age, clip/coil treatments, and no vermian infarction complication. A treatment algorithm for true PICA aneurysms was supported according to pretreatment H and K grade, PICA segments, aneurysm morphology, and 3 types of ischemia linked to the brainstem, cerebellar hemisphere, or vermis.
椎动脉 - 小脑后下动脉（PICA）区域以外的真性PICA动脉瘤罕见，仅有少数几篇论文报道了约30例；尚未有推荐的治疗模式。本研究的目的是呈现真性PICA动脉瘤几种治疗方法的详细临床特征和结果，并提出治疗策略算法。
我们回顾性分析了接受显微手术和血管内治疗的PICA动脉瘤患者的结果。我们还研究了几个因素对改良Rankin量表评分的影响。
血管造影确定了椎动脉 - PICA区域以外的PICA动脉瘤病例（n = 36）。动脉瘤位置包括PICA的延髓前部（n = 7）、延髓外侧（n = 10）、扁桃体延髓部（n = 4）、小脑幕扁桃体部（n = 12）和皮质部（n = 3）。动脉瘤形态如下：夹层型：22例；梭形：6例；囊状：8例。多因素分析显示，年龄（P = 0.028）和无蚓部梗死（P = 0.037）与显著更好的预后相关。5个动脉瘤位置和4个治疗组（夹闭/栓塞、包裹/母动脉闭塞、包裹/母动脉闭塞+搭桥以及包括脑室外引流的观察）之间的预后无显著差异。
本研究表明，与显著更好预后相关的因素包括年龄、夹闭/栓塞治疗以及无蚓部梗死并发症。根据术前H和K分级、PICA节段、动脉瘤形态以及与脑干、小脑半球或蚓部相关的3种缺血类型，支持了真性PICA动脉瘤的治疗算法。
