Wideband Acoustic Absorbance in Otosclerosis: Does Stapedotomy Restore Normal Tympanic Cavity Function?

Area of Science:

• Otolaryngology
• Audiology
• Biomedical Engineering

Background:

• Otosclerosis involves stapes fixation, impairing sound transmission.
• Stapedotomy is a common surgical treatment for otosclerosis.
• The complete restoration of the tympano-ossicular system post-surgery is not fully understood.

Purpose of the Study:

• To assess the tympano-ossicular system in fenestral otosclerosis patients before and after stapedotomy.
• To utilize wideband tympanometry for evaluating acoustic absorbance characteristics.

Main Methods:

• A total of 47 individuals (71 ears) were studied, divided into presurgery otosclerosis, postsurgery, and normal-hearing control groups.
• Wideband tympanometry (226-8,000 Hz) was performed under ambient and pressurized conditions.
• Statistical significance was set at p ≤ 0.05.

Main Results:

• Acoustic absorbance at 226 Hz was low across all groups.
• Distinct absorbance curves were observed between groups from 630 to 5,040 Hz.
• Presurgery otosclerosis showed significantly reduced energy absorbance, particularly at 1,000 Hz, which improved post-surgery but did not normalize.

Conclusions:

• Wideband acoustic absorbance successfully differentiates normal, presurgery otosclerotic, and postsurgery otosclerotic ears.
• Stapedotomy improves hearing but does not fully restore the tympano-ossicular system's physical characteristics.
• Wideband tympanometry is a valuable tool for evaluating otosclerosis and surgical outcomes.