Related Experiment Video
Updated: Oct 3, 2025

Author Spotlight: Advancing Endoscopic Ossiculoplasty – Techniques, Innovations, and Practical Guidance for Clinical Integration
Published on: January 26, 2024
Comparison between incus short process and long process coupling of the vibrant soundbridge in human temporal bones
Lukas Graf1, Jonas Lochner2, Hamidreza Mojallal2
1ENT Department, University Basel Hospital, Basel, Switzerland.
Objective:
The Vibrant Soundbridge (VSB) is one of the most widely used implantable hearing devices. It consists of a vibrating floating mass transducer (FMT) that is connected to a middle ear structure. The standard coupling devices for sensorineural hearing loss are short process (SP) or long process (LP) couplers.
Design And Study Sample:
This study directly compared the electro-mechanical performance of the SP- and LP-coupled FMT of the VSB in the same temporal bone specimen (n = 10). We measured velocity magnitudes and total harmonic distortions (THD) of the stapes (ST) and the round window (RW) using laser Doppler Vibrometry (LDV).
Results:
Comparison shows a maximally 10 dB higher magnitude for the LP coupler at ST and RW for frequencies below 600 Hz, whereas the SP coupler shows a maximally 20 dB higher magnitude at the ST and RW for frequencies above 600 Hz. THD show similar behaviour with less distortion at 500 Hz for the LP coupler and less distortions for the SP coupler in higher frequencies.
Conclusions:
Our experiments showed that the SP coupling may be mechanically favourable, in terms of magnitude and distortion, for the transmission of FMT vibrations at higher frequencies.
Related Concept Videos
The Auditory Ossicles
The aptly named stapes look very much like a stirrup. The three ossicles are unique to mammals, and each plays a role in...
The Cochlea
Anatomy of the Ear
Auditory Pathway
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking...
Hair Cells
Hearing

