Audiological outcome after stapes surgery in relation to prosthesis type

Abstract

Purpose: Different techniques are used to fix crimp and CliP® Piston stapes prostheses to the long process of the incus (LPI). The CliP® Piston provides a stiff connection in contrast to the static bended loop of the crimp prosthesis, which imitates the physiological incudostapedial joint (ISJ) and thereby potentially leads to different hearing outcome.

Methods: In a retrospective single-center study of German-speaking one hundred and ninety patients who underwent stapes surgery CliP® Piston or crimp prostheses between the years of 2016 and 2019 by the same surgeon and in the same setting. Pre- and postoperative bone- (BC) and air-conduction (AC) pure-tone thresholds, pre- and postoperative air-bone gap (ABG) for 0.5, 1, 1.5, 2, 3, 4 kHz and the surgery time were examined.

Results: The postoperative bone conduction thresholds were significantly lower in the frequencies between 0.5 and 3 kHz and the mean ABG was < 10 dB in most cases independent of the prosthesis used. Crimp prosthesis showed a significantly better closure of the ABG at 0.5 kHz.

Conclusions: The audiological outcome after stapes surgery is dependent on the type of prosthesis used, as reflected by the frequency-specific air-bone gap. The better ABG closure with the crimp prosthesis might be the result of the connection to the LPI imitating the physiological ISJ. The crimp prosthesis may be the better choice if use of hearing aids is expected postoperatively.

Keywords: Air–bone gap; Audiological outcome; Prosthesis type; Stapes surgery; Surgery time.

Fig. 1

Different types of stapes prostheses were used for stapes surgery, a) CliP® (CliP Piston àWengen, Heinz Kurz GmbH), b) crimp (MatriX Stapes Prosthesis, Heinz Kurz GmbH)

Fig. 2

Frequencies of surgery time for two different prostheses: CliP® Piston (n = 112) and crimp (n = 78)

Fig. 3

Preoperative air–bone gap (ABG) separately for each measure frequency. The dashed line marks the criterion for the best result after otosclerosis surgery (ABG ≤ 10 dB)

Fig. 4

Preoperative minus postoperative 4PTA_AC difference as function of the preoperative minus postoperative 4PTA_BC difference. Each data point represent number of patients with corresponding values (see scale). PTA indicates pure tone average (0.5, 1, 2, 4 kHz); AC air conduction; BC bone conduction

Fig. 5

Comparison of postoperative air–bone gap for each measure frequency with CliP® Piston and crimp prosthesis. The dashed line marks the criterion for the best result in otosclerosis surgery (≤ 10 dB). Significant differences are indicated by *(p < 0.05)