Speech Perception Gap Is Predictive of an Active Middle Ear Implant Advantage.

OBJECTIVE

Evaluate whether the difference between word recognition score (WRS) obtained unaided under earphone and with a hearing aid (HA), the speech perception gap (SPgap), is predictive of performance with a totally implantable active middle ear implant (AMEI).

STUDY

DESIGN

Retrospective review of systematically collected data.

SETTING

Private otologic practice.

PATIENTS: One hundred thirty six ears (133 patients) with sensorineural hearing loss implanted with an AMEI. Subjects were 73.5% men, with mean age = 61.3 years.

INTERVENTION: Previous AMEI.

MAIN OUTCOME MEASURES: WRS with earphone at phonetically balanced maximum (PB-MAX), and with HA and AMEI at 50 dB HL. Differences between earphone, HA and AMEI word recognition, grouped as positive or negative speech perception gap (+SPgap/-SPgap) between two devices.

RESULTS

A +SPgap (WRS poorer with device than earphone) occurred in 86.0% of patients with HA and 42.3% with the AMEI. Mean SPgap = 24.7% with HA and 3.0% with AMEI (p ≤ 0.001). With a HA +SPgap, AMEI performance was better than HA by an average difference of 23.2% WRS, with AMEI more than HA in 82.9% of subjects. With HA -SPgap, the mean difference was 1.1% correct and AMEI more than HA in 47.4% of subjects (p ≤ 0.001 and p ≤ 0.002, for mean difference and percent of subjects, respectively). The larger the +SPgap (earphone-HA), the greater the advantage of AMEI over HA (r = 0.62, p ≤ 0.001).

CONCLUSION

A speech perception gap between earphone PB-MAX and aided word recognition score suggests a patient may have better speech perception with an AMEI than with his/her hearing aid. This information is useful for counseling patients who are not performing well or are unsatisfied with their hearing aid.