The Effect of Endoscopic Endonasal Transsphenoidal Skull Base Surgery on Cochlear Function

Area of Science:

• Otolaryngology
• Neurosurgery
• Audiology

Background:

• Endoscopic transsphenoidal skull base surgery (ETSS) is a common treatment for sellar and clival lesions.
• The proximity of surgical sites to the inner ear raises concerns about potential hearing effects from bone drilling.

Purpose of the Study:

• To evaluate the impact of bone drilling during ETSS on cochlear function.
• To assess potential noise-induced cochlear damage following ETSS.

Main Methods:

• Prospective study of 18 patients undergoing ETSS.
• Preoperative and postoperative pure-tone audiometry and distortion product otoacoustic emission (DPOAE) measurements were collected.
• Signal-to-noise ratio (SNR) in DPOAEs was analyzed at specific frequencies.

Main Results:

• A significant decrease in DPOAE SNR was observed at 0.5, 1, 2, and 4 kHz in patients treated for pituitary adenoma (p < 0.05).
• No significant changes in DPOAE SNR were found in patients treated for clivus chordoma.
• Pure-tone audiometry revealed no statistically significant postoperative hearing differences (p > 0.05).

Conclusions:

• Bone drilling during ETSS can negatively affect cochlear function in the early postoperative period.
• The findings suggest noise-induced cochlear damage is a potential risk associated with ETSS, particularly for pituitary adenoma surgeries.
• This study provides initial evidence on the extent of cochlear damage from ETSS procedures.