Improving the quality of the ossicular reconstruction by means of real-time monitoring - an experimental study

Introduction The positioning of the prosthesis is crucial for sound transmission during ossicular reconstruction. The reconstruction quality can be objectified in real time using real-time monitoring (RTM). The effect of the RTM was examined in this experimental study for partial (PORP) and total reconstruction (TORP). In addition, the influence of the open and closed eardrum was examined.

Methods The middle ear transfer function (METF) was measured in 13 temporal bone specimens using laser Doppler vibrometry. The vibrations were excited acoustically and electromagnetically. The measurements began on the intact chain, followed by reconstruction with PORP and TORP. The eardrum was loosened and repositioned several times in order to investigate its influence on the METF and to draw conclusions about measurements under surgical conditions.

Results The reconstruction quality measured at METF by RTM can be improved by an average of 15 +/- SD dB for TORP and 5 +/- SD dB [MN1] for PORP. Electromagnetic and acoustic excitation gave comparable results. The influence of the tympanic membrane displacement and repositioning was negligible.

Conclusion The RTM is an effective method for quality control of ossiculoplasty. It is suitable for surgical training in an experimental setting, but also for use in the operating room to improve the coupling of the prosthesis in order to achieve better acoustic results.

Poster-PDF A-1309.pdf

Publication History

Article published online:
13 May 2021