Utility of Extended High-Frequency Audiograms in Clinical Practice.
Level 4 - case-series / case-control
Retrospective case series without a comparison control group
PubMed 37497866 · doi:10.1002/lary.30890
What was done
A retrospective review evaluated patients undergoing conventional (250-8,000 Hz) and extended high-frequency (EHF, 9,000-20,000 Hz) audiometry at a single tertiary otological referral center between April 2021 and August 2022. The analysis was restricted to patients presenting with audiologic symptoms who had normal hearing on conventional testing (pure-tone thresholds <=25 dB HL at <=8 kHz bilaterally). EHF pure-tone average was calculated as the mean air conduction threshold across 9.0, 10.0, 11.2, 12.5, 14.0, 16.0, 18.0, and 20.0 kHz per ear.
What was found
Of 50 patients who underwent EHF testing, 40 had audiologic symptoms and normal conventional audiograms. EHF hearing loss was identified in 25 of 40 patients (62.5%). Patients with EHF hearing loss were more likely to report subjective hearing loss. Age was significantly higher in patients with EHF hearing loss than in those without it, and age positively correlated with the degree of EHF loss; exact correlation coefficients and p-values were not reported in the abstract.
Why it matters
Standard clinical audiometry stops at 8 kHz and may miss high-frequency deficits underlying unexplained audiologic symptoms. These findings indicate that extended high-frequency testing can identify objective deficits in over half of symptomatic patients with otherwise normal routine evaluations.
Limits
The study is limited by a small sample size (n = 40) and a single-center retrospective design without an asymptomatic control cohort. Specific quantitative statistics and diagnostic thresholds for defining EHF hearing loss were not provided in the abstract.
Cited by
- supports Standard clinical hearing tests evaluate frequencies up to 8 kHz, although human hearing can detect frequencies up to 20,000 Hz.