Electrocochleography in round window Vibrant Soundbridge implantation

Area of Science:

• Otolaryngology
• Neuroscience
• Biomedical Engineering

Background:

• Conductive and mixed hearing loss often requires advanced audiological interventions.
• Vibrant Soundbridge (VSB) vibroplasty offers a solution for patients with hearing loss unresponsive to conventional treatments.
• Optimizing the coupling of the VSB floating mass transducer (FMT) to the round window membrane (RWM) is crucial for surgical success.

Purpose of the Study:

• To evaluate the efficacy of intraoperative electrocochleography (ECoG) in optimizing FMT fitting on the RWM.
• To determine if ECoG monitoring improves hearing outcomes in patients undergoing round window vibroplasty.

Main Methods:

• A prospective cohort study involving 26 adult patients with chronic otitis media and moderate to severe hearing loss.
• Thirteen patients underwent round window vibroplasty with intraoperative ECoG monitoring to guide FMT coupling.
• The other 13 patients had vibroplasty without ECoG monitoring.

Main Results:

• No significant preoperative differences in hearing thresholds between the two groups.
• ECoG identified optimal FMT-RWM coupling strategies.
• Postoperative VSB-aided air conduction thresholds showed significantly greater improvement in the ECoG-monitored group (54.6 dB HL) compared to the unmonitored group (41.7 dB HL).

Conclusions:

• Intraoperative ECoG monitoring enhances round window vibroplasty outcomes by optimizing FMT coupling.
• Prompt feedback on compound action potential changes allows surgical adjustments for better device performance.
• Optimal FMT-RWM contact, free from surrounding structures, is key for successful vibroplasty.