Abstract
Twelve patients with severe mixed hearing loss (PTA ranging from 70 to 108 dB HL) were provided with the percutaneous ‘super-bass HC 220’ bone-anchored hearing aid (BAHA) to replace their former hearing aid. Five had previously worn an air-conduction hearing aid (behind-the-ear type, BTE) which could no longer be used because of recurrent otorrhoea; the others had previously worn a conventional (transcutaneous) bone-conduction hearing aid (CBHA) which had caused serious complaints, such as headaches or skin irritation. Free-field speech audiometry in the subgroup of patients who used to wear a CBHA revealed that the maximum intelligibility score with the BAHA was equal to or better than that obtained with the CBHA (range from 0 to + 27%). In three of the five patients who used to wear a BTE, the speech scores were poorer with the BAHA than with the BTE (range from -13 to -40%). For the remaining two patients, the difference in scores was 0 and + 10%. In conclusion, speech recognition with the BAHA HC220 in the patients with severe mixed hearing loss was comparable to, or better than, that with a CBHA. Compared to an air-conduction hearing aid, the results may be considerably poorer. The results of the questionnaire were in good agreement with the measurements and support the conclusions.