Bone and air conduction after stapedectomy.

Area of Science:

• Otolaryngology
• Audiology
• Neurosurgery

Background:

• Otosclerosis is a condition causing hearing loss due to abnormal bone growth in the middle ear.
• While otosclerosis primarily affects air conduction (AC), bone conduction (BC) can also deteriorate.
• Surgical intervention, specifically stapedectomy, has shown potential to improve BC in some otosclerosis patients.

Purpose of the Study:

• To investigate the impact of stapedectomy on both air and bone conduction thresholds in otosclerosis patients.
• To determine if improvements in bone conduction after surgery are related to pre-operative BC levels.

Main Methods:

• A study was conducted on 50 patients (34 female, 16 male; age 24-55) who underwent stapedectomy for otosclerosis.
• Pure-tone audiometry for AC and BC thresholds was performed before and 2-4 months after surgery.
• Only patients achieving air-bone gap closure were included; stapedectomy was performed under local anesthesia.

Main Results:

• Stapedectomy resulted in significant improvement in AC thresholds for all patients.
• A significant improvement in BC thresholds (6-12 dB) was observed across all tested frequencies.
• Improvement in BC was significant in patients with pre-operative BC thresholds ≥ 30 dB, but not in those with thresholds < 30 dB.

Conclusions:

• Successful stapedectomy not only improves air conduction but can also enhance bone conduction in otosclerosis.
• Otosclerosis may involve a reversible 'pseudo' bone conduction hearing loss, particularly in individuals with poorer pre-operative BC thresholds.
• The degree of pre-operative bone conduction threshold influences the potential for BC improvement after stapedectomy.