Santhumayor Brandon A, Mashiach Elad, Meng Ying, Rotman Lauren, Golub Danielle, Bernstein Kenneth, Vasconcellos Fernando De Nigris, Silverman Joshua S, Harter David H, Golfinos John G, Kondziolka Douglas
Department of Neurosurgery, New York University Langone Health, New York , New York , USA.
Department of Radiation Oncology, New York University Langone Health, New York , New York , USA.
Neurosurgery. 2025 Mar 1;96(3):650-659. doi: 10.1227/neu.0000000000003140. Epub 2024 Aug 12.
Hydrocephalus after Gamma Knife® stereotactic radiosurgery (SRS) for vestibular schwannomas is a rare but manageable occurrence. Most series report post-SRS communicating hydrocephalus in about 1% of patients, thought to be related to a release of proteinaceous substances into the cerebrospinal fluid. While larger tumor size and older patient age have been associated with post-SRS hydrocephalus, the influence of baseline ventricular anatomy on hydrocephalus risk remains poorly defined.
A single-institution retrospective cohort study examining patients who developed symptomatic communicating hydrocephalus after undergoing Gamma Knife® SRS for unilateral vestibular schwannomas from 2011 to 2021 was performed. Patients with prior hydrocephalus and cerebrospinal fluid diversion or prior surgical resection were excluded. Baseline tumor volume, third ventricle width, and Evans Index (EI)-maximum width of the frontal horns of the lateral ventricles/maximum internal diameter of the skull-were measured on axial postcontrast T1-weighted magnetic resonance imaging.
A total of 378 patients met the inclusion criteria; 14 patients (3.7%) developed symptomatic communicating hydrocephalus and 10 patients (2.6%) underwent shunt placement and 4 patients (1.1%) were observed with milder symptoms. The median age of patients who developed hydrocephalus was 69 years (IQR, 67-72) and for patients younger than age 65 years, the risk was 1%. For tumor volumes <1 cm 3 , the risk of requiring shunting was 1.2%. The odds of developing symptomatic hydrocephalus were 5.0 and 7.7 times higher in association with a baseline EI > 0.28 ( P = .024) and tumor volume >3 cm 3 ( P = .007), respectively, in multivariate analysis. Fourth ventricle distortion on pre-SRS imaging was significantly associated with hydrocephalus incidence ( P < .001).
Patients with vestibular schwannoma with higher baseline EI, larger tumor volumes, and fourth ventricle deformation are at increased odds of developing post-SRS hydrocephalus. These patients should be counseled regarding risk of hydrocephalus and carefully monitored after SRS.
伽玛刀立体定向放射外科治疗（SRS）前庭神经鞘瘤后发生脑积水是一种罕见但可处理的情况。大多数系列报道显示，SRS术后交通性脑积水在约1%的患者中出现，认为这与蛋白质类物质释放到脑脊液中有关。虽然肿瘤体积较大和患者年龄较大与SRS术后脑积水有关，但基线脑室解剖结构对脑积水风险的影响仍不明确。
进行了一项单机构回顾性队列研究，研究对象为2011年至2021年接受伽玛刀SRS治疗单侧前庭神经鞘瘤后出现症状性交通性脑积水的患者。排除既往有脑积水和脑脊液分流或既往手术切除史的患者。在轴位增强T1加权磁共振成像上测量基线肿瘤体积、第三脑室宽度和埃文斯指数（EI）——侧脑室额角最大宽度/颅骨最大内径。
共有 378名患者符合纳入标准；14名患者（3.7%）出现症状性交通性脑积水，10名患者（2.6%）接受了分流置管，4名患者（1.1%）症状较轻予以观察。发生脑积水患者的中位年龄为69岁（四分位间距，67 - 72岁），65岁以下患者的风险为1%。对于肿瘤体积<1 cm³ 的患者，需要分流的风险为1.2%。在多变量分析中，基线EI > 0.28（P = .024）和肿瘤体积>3 cm³（P = .007）时，出现症状性脑积水的几率分别高出5.0倍和7.7倍。SRS术前成像上的第四脑室变形与脑积水发生率显著相关（P < .001）。
基线EI较高、肿瘤体积较大且第四脑室变形的前庭神经鞘瘤患者发生SRS术后脑积水的几率增加。应向这些患者告知脑积水风险，并在SRS术后进行密切监测。
