Department of Neurosurgery, Basel University Hospital, Basel, Switzerland.
Division of Diagnostic and Interventional Neuroradiology, Department of Radiology, Basel University Hospital, Basel, Switzerland.
Neurosurgery. 2018 Feb 1;82(2):202-210. doi: 10.1093/neuros/nyx143.
The goals of treating Koos grade IV vestibular schwannomas are to relieve brainstem compression, preserve or restore neurological function, and achieve long-term tumor control while minimizing tumor- and treatment-related morbidity.
To propose a treatment paradigm involving the intentional near-total removal of Koos grade IV vestibular schwannomas, in which a small amount of residual tumor is not dissected off the cisternal portion of the facial nerve. Patients are then followed by a wait-and-scan approach. Any subsequent volumetric progression of the residual tumor is treated with radiosurgery.
This is a case series of 44 consecutive unselected patients who underwent intended near-total resection of a Koos grade IV vestibular schwannoma through a retrosigmoid approach from January 2009 to December 2015. Pre- and postoperative volumetric analyses were performed on routine magnetic resonance imaging sequences (constructive interference in steady state and gadolinium-enhanced T1-weighted sequence).
The mean preoperative tumor volume was 10.9 cm3. The mean extent of resection was 89%. At the last clinical follow-up, facial nerve function was good [House and Brackmann (HB) I-II] in 89%, fair (HB III) in 9%, and poor (HB IV-VI) in 2% of the patients. At the last radiological follow-up, the residual tumor had become smaller or remained the same size in 84% of patients. Volumetric progression was negatively correlated with the original extent of resection and positively correlated with postoperative residual tumor volume (P = .01, P < .001, respectively).
Intended near-total removal results in excellent preservation of facial nerve function and has a low recurrence rate. Any progressive residual tumor may be treated by radiosurgery.
治疗 Koos 分级 IV 型前庭神经鞘瘤的目标是缓解脑干压迫，保留或恢复神经功能，并实现长期肿瘤控制，同时将肿瘤和治疗相关的发病率降至最低。
提出一种治疗方案，涉及有意图地接近全切除 Koos 分级 IV 型前庭神经鞘瘤，其中一小部分肿瘤不会从面神经的池部解剖。然后，患者通过等待和扫描的方法进行随访。任何随后的残留肿瘤体积进展都采用放射外科治疗。
这是一项连续的 44 例未经选择的患者的病例系列研究，他们在 2009 年 1 月至 2015 年 12 月期间通过后路乙状窦入路接受了 Koos 分级 IV 型前庭神经鞘瘤的有意图的近全切除。术前和术后体积分析是在常规磁共振成像序列（稳态构造干扰和钆增强 T1 加权序列）上进行的。
平均术前肿瘤体积为 10.9cm3。平均切除程度为 89%。在最后一次临床随访时，89%的患者面神经功能良好（House 和 Brackmann [HB] I-II），9%的患者面神经功能尚可（HB III），2%的患者面神经功能较差（HB IV-VI）。在最后一次放射学随访时，84%的患者残留肿瘤变小或保持不变。肿瘤体积进展与原始切除程度呈负相关，与术后残留肿瘤体积呈正相关（P =.01，P <.001）。
有意图的近全切除可极好地保留面神经功能，复发率低。任何进行性的残留肿瘤都可以采用放射外科治疗。
