[Relative value of BAHA testing for the postoperative audiological outcome].

BACKGROUND: Bone-anchored hearing aids provide a therapy option for patients with conductive and mixed hearing loss, with the possibility of audiological rehabilitation. Test rod and tension headband offer the patient a preoperative impression of their postoperative hearing. The aim of this study was to evaluate the tools available for preoperative assessment of candidates for bone-anchored hearing aids and to ascertain predictive audiometric values.
METHODS: Following implantation of a BAHA Compact system, sound and speech audiograms were performed in each of 16 patients with the bone-anchored BAHA device and with test rod and tension headband.
RESULTS: Both with the BAHA and with the test devices, closure of the air-bone gap occurred and resulted in a clear improvement in hearing threshold and speech perception. The threshold increase with the BAHA was 9 dB greater on average (mean) than that measured with the test rod and the tension headband. Examinaation of speech perception indicated a mean advantage of 14-20% for the anchored BAHA system over the tension headband in monosyllabic testing.
CONCLUSION: Preoperative testing before providing a BAHA system is a good way of predicting what level of hearing and speech perception can be expected after implantation.