Auditory brain stem responses in patients with acoustic neuromas

Area of Science:

• Audiology
• Neuroscience
• Otolaryngology

Background:

• Early diagnosis of acoustic neuromas is crucial for effective treatment.
• Acoustic neuromas, benign tumors on the auditory nerve, can cause hearing loss and other neurological symptoms.
• Functional audiological tests are essential for differentiating cochlear from retrocochlear pathologies.

Purpose of the Study:

• To evaluate the efficacy of auditory brain stem response (ABR) in diagnosing acoustic neuromas.
• To identify key indicators within ABR for detecting retrocochlear lesions.
• To assess the influence of patient demographics and tumor characteristics on ABR results.

Main Methods:

• Auditory brain stem response (ABR) examination was performed on 27 patients with surgically confirmed acoustic neuromas.
• The interaural latency difference of the J5 wave (IT5) was identified as the primary indicator.
• Stimulus presentation was optimized to highlight response adaptation in the presence of tumors.

Main Results:

• The interaural latency difference of the J5 wave (IT5) is a key indicator for retrocochlear disease.
• Women exhibited significantly shorter J5 latency values (approx. 0.25 msec) compared to men.
• No significant correlation was found between tumor size and IT5, and the technique is effective even with hearing impairment.
• Response adaptation was a common finding in patients with acoustic neuromas.

Conclusions:

• Auditory brain stem response (ABR) is the most reliable functional audiological test for detecting retrocochlear lesions like acoustic neuromas.
• The IT5 measurement is a valuable diagnostic tool, with specific latency differences noted between sexes.
• Optimized ABR stimulus presentation can enhance diagnostic accuracy for acoustic neuromas.