Calculated versus measured pure tone bone conduction 3 kHz thresholds in sudden sensorineural hearing loss

Area of Science:

• Audiology
• Otolaryngology
• Neurotology

Background:

• Sudden sensorineural hearing loss (SSNHL) is a complex condition with various potential etiologies.
• Accurate audiometric assessment is crucial for diagnosis and management of SSNHL.

Purpose of the Study:

• To compare measured bone conduction thresholds at 3 kHz with calculated thresholds in patients with newly diagnosed SSNHL.
• To determine if discrepancies in 3 kHz bone conduction thresholds can indicate specific underlying causes of SSNHL.

Main Methods:

• Retrospective chart review of pure tone audiograms from patients diagnosed with SSNHL.
• Analysis of 157 SSNHL cases, including idiopathic, vestibular schwannoma, and Ménière's disease groups.
• Correlation and difference analysis between measured and calculated 3 kHz bone conduction thresholds.

Main Results:

• A strong correlation (r=0.887, p<0.001) was found between measured and calculated 3 kHz bone conduction thresholds across all SSNHL patients.
• The mean difference between measured and calculated thresholds was small in idiopathic and Ménière's disease groups.
• A significantly larger mean difference was observed in the vestibular schwannoma group compared to the idiopathic group (p=0.013).

Conclusions:

• The 3 kHz frequency provides significant audiometric information in SSNHL assessment.
• A notable difference between measured and calculated 3 kHz bone conduction thresholds suggests a potential vestibular schwannoma.
• Routine independent measurement of 3 kHz bone conduction thresholds is recommended for suspected SSNHL to aid in etiological diagnosis.