Stapedius Reflex in Functional Hearing Loss

Abstract

Functional and inner-ear hearing loss must be differentiated to diagnose functional hearing loss based only on the stapedius reflex (SR). We statistically compared values obtained by subtracting the pure-tone audiometry threshold from the SR threshold in those with functional or inner-ear hearing loss. At hearing of less than 60 dB HL, no significant difference was seen between those with functional and inner-ear hearing loss. At 70 dB HL or 80 dB HL, values were statistically lower in those with functional hearing loss than with inner-ear hearing loss (p<0.01). At 90 dB HL or more, the value was 0 or less in many with functional hearing loss. Evaluating hearing loss using the SR alone is therefore not possible in functional hearing loss at less than 60 dB HL. It is possible, however, to diagnose some cases of functional hearing loss at 70 dB HL or 80 dB HL and in many cases of functional hearing loss of 90 dB HL or more.