Department of Otolaryngology-Head & Neck Surgery, Harvard Medical School, Boston, Massachusetts, U.S.A.
Otopathology Laboratory, Massachusetts Eye and Ear, Boston, Massachusetts, U.S.A.
Laryngoscope. 2024 Feb;134(2):945-953. doi: 10.1002/lary.30900. Epub 2023 Jul 26.
Current surgical techniques aim to preserve intracochlear structures during cochlear implant (CI) insertion to maintain residual cochlear function. The optimal technique to minimize damage, however, is still under debate. The aim of this study is to histologically compare insertional trauma and intracochlear tissue formation in humans with a CI implanted via different insertion techniques.
One recent temporal bone from a donor who underwent implantation of a full-length CI (576°) via round window (RW) insertion was compared with nine cases implanted via cochleostomy (CO) or extended round window (ERW) approach. Insertional trauma was assessed on H&E-stained histological sections. 3D reconstructions were generated and virtually re-sectioned to measure intracochlear volumes of fibrosis and neo-ossification.
The RW insertion case showed electrode translocation via the spiral ligament. 2/9 CO/ERW cases showed no insertional trauma. The total volume of the cochlea occupied by fibro-osseous tissue was 10.8% in the RW case compared with a mean of 30.6% (range 8.7%-44.8%, N = 9) in the CO/ERW cases. The difference in tissue formation in the basal 5 mm of scala tympani, however, was even more pronounced when the RW case (12.3%) was compared with the cases with a CO/ERW approach (mean of 93.8%, range 81% to 100%, N = 9).
Full-length CI insertions via the RW can be minimally traumatic at the cochlear base without inducing extensive fibro-osseous tissue formation locally. The current study further supports the hypothesis that drilling of the cochleostomy with damage to the endosteum incites a local tissue reaction.
4: Case-control study Laryngoscope, 134:945-953, 2024.
目前的外科技术旨在在植入人工耳蜗（CI）时保护耳蜗内结构，以维持残余耳蜗功能。然而，最小化损伤的最佳技术仍存在争议。本研究旨在通过不同的插入技术比较人类 CI 植入时的插入性创伤和耳蜗内组织形成。
将一位接受过全长 CI（576°）经圆窗（RW）插入的供体的最近颞骨与 9 例经耳蜗造口术（CO）或延伸圆窗（ERW）入路植入的病例进行比较。在 H&E 染色的组织切片上评估插入性创伤。生成 3D 重建并进行虚拟切片以测量纤维化和新生骨的耳蜗内体积。
RW 插入病例显示电极通过螺旋韧带移位。9 例 CO/ERW 病例中有 2 例无插入性创伤。RW 病例纤维化和新生骨组织占据耳蜗的总容积为 10.8%，而 CO/ERW 病例的平均容积为 30.6%（范围 8.7%-44.8%，N=9）。然而，当将 RW 病例（12.3%）与 CO/ERW 方法的病例（平均 93.8%，范围 81%至 100%，N=9）进行比较时，基底 5mm 处鼓阶的组织形成差异更为明显。
RW 全长 CI 插入术在耳蜗基底处可以最小化创伤，而不会在局部引起广泛的纤维-骨组织形成。本研究进一步支持了这样的假设，即耳蜗造口术的钻孔损伤骨内膜会引起局部组织反应。
4：病例对照研究喉镜，134：945-953，2024。
