Clinical Cases / Clinician

A poor ear that is not as poor as it looks Clinician

Vignette

A 60-year-old has a normal right ear and a profoundly impaired left ear after previous surgery. The initial unmasked left-ear audiogram shows thresholds that mirror the right ear, offset by about 50 dB.

-100204060801001202505001k2k4k8kFrequency (Hz)Hearing level (dB HL)
  • O Right ear, air
  • X Left ear, air
  • < Right ear, bone
  • > Left ear, bone

Signature: Air and bone conduction both within normal limits at every frequency, with no air–bone gap.

Figure 1. The audiogram. The right ear (shown) is normal. The unmasked left-ear curve parallels it at roughly 50–60 dB.

Question

What is the most likely explanation for the unmasked left-ear curve?

References

  1. [7] StatPearls contributors (2022). Audiology clinical masking.
  2. [4] Katz J, Lezynski J (2015). Clinical masking.