SPEECH-DISCRIMINATION SCORES OF POSTLINGUALLY DEAF ADULTS IMPLANTED WITH THE COMBI-40 COCHLEAR IMPLANT

The aim of the study was to assess the speech discrimination ability o f postlingually deaf adults implanted with the Combi 40 cochlear impla nt and to compare the results with the postoperative data published fo r other devices. The postoperative open and closed set speech percepti on performance of 21 consecutive patients was tested using a standardi zed test battery comprising a number, monosyllable, sentence, consonan t and vowel discrimination test as well as a rhyme test in the sound o nly condition. Mean values achieved for each test 1, 6 and 12 months a fter ''switch on'' were evaluated. The results demonstrate that all pa tients have a substantial benefit from their implant and show a contin uous improvement in their speech perception abilities with increased d evice experience. The mean percentages of correct answers after 12 mon ths were 93.4 for numbers, 44.6 for monosyllables, 78.5 for sentences, 67.6 for the rhyme test, 59.8 for vowel, and 67.3 for consonant discr imination. Preoperatively, the mean discrimination score for monosylla bles was 0%. The speech discrimination scores of our patients were sim ilar or higher than described for similar patient groups implanted wit h other devices. The high stimulation rate of the implant system using the continuous interleaved speech processing strategy as well as a de ep atraumatic electrode insertion into the apicalmost regions of the s cala tympani may be the reason for good performance.