Aschendorff Antje, Briggs Robert, Brademann Goetz, Helbig Silke, Hornung Joachim, Lenarz Thomas, Marx Mathieu, Ramos Angel, Stöver Timo, Escudé Bernard, James Chris J
University of Freiburg, Freiburg, Germany.
Audiol Neurootol. 2017;22(3):169-179. doi: 10.1159/000480345. Epub 2017 Oct 24.
The Nucleus CI532 cochlear implant incorporates a new precurved electrode array, i.e., the Slim Modiolar electrode (SME), which is designed to bring electrode contacts close to the medial wall of the cochlea while avoiding trauma due to scalar dislocation or contact with the lateral wall during insertion. The primary aim of this prospective study was to determine the final position of the electrode array in clinical cases as evaluated using flat-panel volume computed tomography.
Forty-five adult candidates for unilateral cochlear implantation were recruited from 8 centers. Eleven surgeons attended a temporal bone workshop and received further training with a transparent plastic cochlear model just prior to the first surgery. Feedback on the surgical approach and use of the SME was collected via a questionnaire for each case. Computed tomography of the temporal bone was performed postoperatively using flat-panel digital volume tomography or cone beam systems. The primary measure was the final scalar position of the SME (completely in scala tympani or not). Secondly, medial-lateral position and insertion depth were evaluated.
Forty-four subjects received a CI532. The SME was located completely in scala tympani for all subjects. Pure round window (44% of the cases), extended round window (22%), and inferior and/or anterior cochleostomy (34%) approaches were successful across surgeons and cases. The SME was generally positioned close to the modiolus. Overinsertion of the array past the first marker tended to push the basal contacts towards the lateral wall and served only to increase the insertion depth of the first electrode contact without increasing the insertion depth of the most apical electrode. Complications were limited to tip fold-overs encountered in 2 subjects; both were attributed to surgical error, with both reimplanted successfully.
The new Nucleus CI532 cochlear implant with SME achieved the design goal of producing little or no trauma as indicated by consistent scala tympani placement. Surgeons should be carefully trained to use the new deployment method such that tip fold-overs and over insertion may be avoided.
Nucleus CI532人工耳蜗植入体采用了一种新的预弯曲电极阵列，即细螺旋电极（SME），其设计目的是使电极触点靠近耳蜗内侧壁，同时避免在插入过程中因鼓阶脱位或与外侧壁接触而造成创伤。这项前瞻性研究的主要目的是使用平板容积计算机断层扫描评估临床病例中电极阵列的最终位置。
从8个中心招募了45名单侧人工耳蜗植入的成年候选人。11名外科医生参加了颞骨研讨会，并在首次手术前使用透明塑料耳蜗模型接受了进一步培训。通过针对每个病例的问卷收集有关手术方法和SME使用情况的反馈。术后使用平板数字容积断层扫描或锥形束系统进行颞骨计算机断层扫描。主要测量指标是SME的最终鼓阶位置（是否完全位于鼓阶内）。其次，评估其内外侧位置和插入深度。
44名受试者接受了CI532植入。所有受试者的SME均完全位于鼓阶内。纯圆窗入路（44%的病例）、扩大圆窗入路（22%）以及下和/或前耳蜗造瘘入路（34%）在外科医生和病例中均取得成功。SME通常位于靠近蜗轴的位置。阵列超过第一个标记的过度插入往往会将基底触点推向外侧壁，并且只会增加第一个电极触点的插入深度，而不会增加最顶端电极的插入深度。并发症仅限于2名受试者出现的电极尖端折叠；两者均归因于手术失误，且均成功进行了再次植入。
带有SME的新型Nucleus CI532人工耳蜗植入体实现了设计目标，即如鼓阶位置一致所示，产生很少或没有创伤。应仔细培训外科医生使用新的植入方法，以避免电极尖端折叠和过度插入。
