Faculty of Medicine, Department of Otorhinolaryngology, Medical Center - University of Freiburg, University of Freiburg, Freiburg, Germany.
Department of Otorhinolaryngology - Head and Neck Surgery, University of Freiburg, Killianstrasse 5, 79106, Freiburg, Germany.
Eur Arch Otorhinolaryngol. 2024 Mar;281(3):1215-1220. doi: 10.1007/s00405-023-08212-5. Epub 2023 Sep 29.
The influence of cochlear morphology and electrode array design on scalar position and dislocation rates is of great interest in CI surgery. The aim of this study is to evaluate scalar position and specific points of dislocation in relation to cochlear morphology in patients implanted with a new slim perimodiolar electrode array.
Patients were implanted using the slim modiolar electrode array (= SMA) (= 532/632 electrode array of Cochlear). Postoperative imaging was performed via cone beam computed tomography (CBCT) and the scans were analyzed regarding cochlear morphology (distances A and B and cochlear height), scalar location of the electrode array, basal insertion depth and apical insertion angle. Furthermore, electrode array design and surgical protocols were evaluated.
81 ears implanted with the SMA were retrospectively included. We evaluated 3 electrode array tip fold over intraoperatively via X-ray imaging and performed revision during the same surgery. The CBCT scans showed 76 initial scala tympani (ST) insertions without dislocation. Two ears showed a dislocated array, one at 77° and the other at 163°. Three arrays were inserted into scala vestibuli (SV) via cochleostomy. These patients showed no signs of obliteration. Cochlear morphology showed no influence on angular insertion depth and scalar position.
The SMA showed a very low rate of scalar dislocations due to its slim electrode array design (2.7%). We could find a learning curve regarding the handling and the risk of dislocation and tip fold over with this electrode array. The rate of intraoperative tip fold over detection via X-ray imaging was 3.7%. Therefore, we highly recommend X-ray imaging and transimpedance matrix measurements within the surgery protocol. Scala vestibuli insertions happened in patients with cochleostomy only. We could identify two specific points of dislocation depending on electrode array design.
耳蜗形态和电极阵列设计对人工耳蜗植入术中文本位置和脱位率的影响具有重要意义。本研究旨在评估与耳蜗形态相关的新型细薄中周电极阵列植入患者的文本位置和特定脱位点。
使用细薄中周电极阵列（=SMA）（= Cochlear 的 532/632 电极阵列）对患者进行植入。通过锥形束计算机断层扫描（CBCT）进行术后成像，并对耳蜗形态（距离 A 和 B 以及耳蜗高度）、电极阵列的标量位置、基底插入深度和顶端插入角度进行分析。此外，还评估了电极阵列设计和手术方案。
回顾性纳入 81 例植入 SMA 的耳朵。我们通过 X 射线成像评估了 3 例术中电极阵列尖端折叠，并在同一手术中进行了修正。CBCT 扫描显示 76 例初始耳蜗鼓阶（ST）无脱位。2 例出现数组脱位，1 例为 77°，另 1 例为 163°。3 个数组通过耳蜗造口术插入前庭耳蜗（SV）。这些患者没有闭塞迹象。耳蜗形态对角度插入深度和标量位置没有影响。
由于 SMA 的电极阵列设计很薄，因此其文本脱位率非常低（2.7%）。我们可以发现处理和脱位以及尖端折叠的学习曲线与这种电极阵列有关。通过 X 射线成像检测术中尖端折叠的发生率为 3.7%。因此，我们强烈建议在手术方案中进行 X 射线成像和跨阻抗矩阵测量。仅在耳蜗造口术患者中出现 SV 插入。我们可以根据电极阵列设计识别出两个特定的脱位点。
