Stapes piston insertion depth and clinical correlations

Abstract

Background: The insertion of the stapes piston within the vestibule provides the physical basis for a successful stapedotomy. An insertion depth of 0.5 mm is recommended to avoid the dislocation of the stapes prosthesis (e.g. sneezing).

Aims: The objective of this study is to analyze the depth of stapes prosthesis insertion and its correlation with clinical outcome.

Material and methods: We observed in a retrospective case series 39 otosclerosis patients after a stapedotomy and a postoperative performed flat panel tomography/cone beam CT. The evaluation included the radiologically found depth of prosthesis insertion within the vestibule, the vestibule depth, and the correlation with the bone conduction (BC) threshold, vertigo, and tinnitus.

Results: Insertion depth varied between 0.2 and 1.6 mm (mean 0.74 mm). The ratio of insertion depth versus the vestibule depth was between 8% and 59% (mean 26.6%). We observed no correlation between the insertion depth, the length of the prosthesis, the ratio of insertion depth/vestibule depth, postoperative BC, appearance of vertigo, or tinnitus.

Conclusions and significance: In our group, we observed no significant relation between insertion depth of the stapes piston, postoperative vertigo, tinnitus, or decrease of the BC.

Chinese abstract

背景：将镫骨活塞插入前庭为镫骨切开术的成功提供了客观条件。建议插入深度为0.5 mm, 以避免镫骨假体错位（例如: 打喷嚏时）。

目的：分析镫骨假体植入深度及其与临床结果的关系。

材料和方法：我们在一组回顾性病例系列中观察了39例接受镫骨切开术的耳硬化症患者以及术后进行的平板断层扫描/锥束CT。评估包括放射学方法确定的前庭内假体植入深度、前庭深度及其与骨传导（BC）阈值、眩晕和耳鸣的相关性。

结果：插入深度在0.2～1.6 mm之间（平均0.74 mm）。插入深度与前庭深度之比在8%至59%之间（平均26.6%）。据观察, 插入深度、假体长度、插入深度与前庭深度之比、术后BC、眩晕或耳鸣之间没有相关性。

结论与意义：镫骨活塞插入深度、术后眩晕、耳鸣、BC下降之间无明显关系。

Keywords:

• Otosclerosis
• stapes prosthesis length
• vertigo

Ethical approval

The study was approved by the institutional review board of the Klinikum Bielefeld, Germany (IRB-klibi-HNO-2017/06). Patients gave their written informed consent for the use of their clinical records in this study. The study was conducted ethically in accordance with the World Medical Association Declaration of Helsinki.

Author contributions

S. Gil Mun, Assistant, drafting; E. Scheffner, Assistant, drafting; H.B. Gehl, Head of Bielefeld Radiology, discussion of radiological results, co-writing; E. Boga, Consultant performing radiological scans; K. Wilms, Assistant, collecting data, discussion; S. Müller, Consultant, performing statistics; P. Mittmann, Consultant, performing statistics; H. Sudhoff, Head of Bielefeld Otolaryngology Department, co-writing; G. Rademacher, Consultant, performing radiological scans; S. Mutze, Head of Berlin Radiology, performing radiological scans; I. Todt, Consultant, idea, surgeon, writing.

Disclosure statement

No potential conflict of interest was reported by the authors.