Wakuta Naoki, Yoshioka Tsutomu, Irie Yukino, Tsugu Hitoshi, Abe Hiroshi
Department of Neurosurgery, Fukuoka Red Cross Hospital, Fukuoka, Japan.
Department of Neurosurgery Fukuoka University Hospital, School of Medicine, Fukuoka University, Fukuoka, Japan.
Surg Neurol Int. 2024 Jun 21;15:213. doi: 10.25259/SNI_285_2024. eCollection 2024.
Aneurysmal formation after stereotactic radiosurgery (SRS) for vestibular schwannoma (VS) is a rare complication. Its characteristics and the best treatment strategies remain controversial, and the clinical course is especially unknown because reported aneurysms are first incidentally detected, or aneurysmal rupture occurs suddenly, and they are treated immediately.
A 68-year-old man who underwent SRS for VS 20 years ago presented with subarachnoid hemorrhage (SAH) due to rupture of a radiation-induced fusiform anterior inferior cerebellar artery aneurysm. He was treated with parent artery occlusion, resulting in a modified Rankin scale grade 2. This report illustrates the first case of detected aneurysm formation before rupture with retrospective magnetic resonance imaging evaluation.
We describe the possible risk of rapid progression and rupture of aneurysms, focusing on the interval from SRS to aneurysmal formation. The period of formation of SRS-induced aneurysms is suspected to vary from years to decades regardless of radiation doses; however, aneurysms estimated as pseudoaneurysms have an extremely high risk of rupture within a few years, even when small in size. If aneurysms are discovered unruptured, there are some advantages in not only the prevention of poor prognosis due to SAH but also in the availability of optional therapeutic strategies using revascularization. Long-term annual follow-up, including vessel examination, is warranted not only to assess tumor status but also for early detection of any vascular lesions.
立体定向放射外科治疗（SRS）前庭神经鞘瘤（VS）后动脉瘤形成是一种罕见的并发症。其特征和最佳治疗策略仍存在争议，且临床过程尤其不明，因为已报道的动脉瘤要么是首次偶然发现，要么是突然发生动脉瘤破裂并立即接受治疗。
一名20年前接受SRS治疗VS的68岁男性，因放射性诱发的梭形小脑前下动脉瘤破裂出现蛛网膜下腔出血（SAH）。他接受了供血动脉闭塞治疗，结果改良Rankin量表评分为2级。本报告阐述了首例通过回顾性磁共振成像评估在破裂前检测到动脉瘤形成的病例。
我们描述了动脉瘤快速进展和破裂的可能风险，重点关注从SRS到动脉瘤形成的间隔时间。SRS诱发动脉瘤的形成时间据推测从数年到数十年不等，与辐射剂量无关；然而，估计为假性动脉瘤的动脉瘤即使体积较小，在几年内也有极高的破裂风险。如果发现动脉瘤未破裂，不仅在预防SAH导致的不良预后方面有优势，而且在使用血管重建的可选治疗策略方面也有优势。长期每年随访，包括血管检查，不仅有必要评估肿瘤状态，而且有助于早期发现任何血管病变。
