Department of ENT - HNS, European Institute for Otorhinolaryngology - Head - Neck Surgery, Sint Augustinus, GZA Hospital, Antwerp, Belgium.
Department of Neurosugery, NeurochirurgieGroep, Sint Augustinus, GZA Hospital, Antwerp, Belgium.
J Int Adv Otol. 2020 Apr;16(1):53-57. doi: 10.5152/iao.2020.8002.
To assess the incidence and onset of cochlear obliteration after translabyrinthine and retrosigmoid vestibular schwannoma surgery.
We retrospectively identified a consecutive series of eighty ears in eighty vestibular schwannoma patients who were treated via a translabyrinthine or retrosigmoid approach by a single neuro-otological surgical team in a tertiary referral center from May 2011 to January 2018. Postoperative, high- resolution T2-weighted turbo spin echo three-dimensional magnetic resonance (MR) images of the posterior fossa were evaluated at the level of the membranous labyrinth and internal auditory canal. Perilymphatic patency of the vestibule, basal, and apical cochlear turns were scored and classified as patent, hypointense, partially obliterated, or completely obliterated.
Twenty-five vestibular schwannomas were treated with surgery via a translabyrinthine approach, and fifty-five were treated using a retrosigmoid approach; of these, 8% and 65%, respectively, showed no signs of perilymphatic alterations in the basal or apical turns, while 84% and 20%, respectively, showed partial or complete obliteration in the basal or apical turns with a mean postoperative interval of 127 and 140 days, respectively. All the patients who underwent multiple MR scans and had a completely patent perilymphatic system on the first postoperative scan remained patent during subsequent scans; 16% of the patients showed worsened perilymphatic appearance. The onset of cochlear obliteration occurred within 2-7 months in most translabyrinthine patients.
These findings may support the need for simultaneous cochlear electrode or dummy implantation in translabyrinthine surgery. Second-stage implantation could be feasible in cases where a retrosigmoid approach is used; however, the implantation should be considered within the initial months to avoid cochlear obliteration. Findings on the first postoperative MR could indicate the need for intensified MR follow-up and may even predict the occurrence of cochlear obliteration.
评估经迷路和乙状窦后颅神经鞘瘤手术后耳蜗闭塞的发生率和发病时间。
我们回顾性地确定了 80 例前庭神经鞘瘤患者的 80 只耳朵，这些患者均由同一组神经耳科手术团队于 2011 年 5 月至 2018 年 1 月在三级转诊中心通过迷路或乙状窦后入路进行治疗。术后，对 80 例患者的 80 只耳朵进行高分辨率 T2 加权涡轮自旋回波三维磁共振（MR）图像检查，扫描部位为膜迷路和内耳道水平。对前庭、基底和顶部耳蜗转的外淋巴通畅情况进行评分，并分类为通畅、低信号、部分闭塞或完全闭塞。
25 例前庭神经鞘瘤患者采用迷路入路手术治疗，55 例患者采用乙状窦后入路手术治疗；其中，8%和 65%的患者在基底或顶部转无外淋巴改变的迹象，而 84%和 20%的患者在基底或顶部转分别出现部分或完全闭塞，平均术后间隔分别为 127 和 140 天。所有接受多次磁共振扫描且第一次术后扫描显示外淋巴系统完全通畅的患者在随后的扫描中保持通畅；16%的患者外淋巴外观恶化。大多数迷路入路患者的耳蜗闭塞发生在术后 2-7 个月内。
这些发现可能支持在迷路手术中同时进行耳蜗电极或假植入的需要。对于乙状窦后入路，二期植入是可行的；然而，植入应在最初几个月内进行，以避免耳蜗闭塞。首次术后磁共振检查结果可能表明需要加强磁共振随访，甚至可能预测耳蜗闭塞的发生。
