ABSTRACT
OBJECTIVE: The aim of the present study was to evaluate the effect of stimulation rate on speech perception and sound quality for the fine structure strategy FS4 and the envelope-based strategy high definition continuous interleaved sampling (HDCIS). STUDY DESIGN: Randomized crossover trial with four conditions. SETTING: Tertiary referral. PATIENTS: Twenty-six postlingually deafened adult cochlear implant (CI) recipients were included. INTERVENTION: All subjects were equipped with four coding strategies: FS4 with high rate on the envelope channels (on average 1376âpps/ch), FS4 low rate (750âpps/ch), and HDCIS with the same high and low rates. A "flat-charge map" was used for all four strategies. Only the loudness was balanced between programs. All tests were performed acutely in a double blind manner and a randomized sequence. MAIN OUTCOME MEASURES: Monosyllables in quiet and subjective sound quality. RESULTS: Mean monosyllables scores at 65âdB in quiet were 25.5% correct with HDCIS low rate, 27.2% correct with HDCIS high rate, 25.2% with FS4 low rate, and 33.1% with FS4 high rate. Performance with high stimulation rates was significantly higher than with the low rate settings. Subjective sound quality measured with visual analogue scales showed that for naturalness of speech, the improvement with a high rate version was only evident with the FS4 strategy. In both FS4 and HDCIS, higher stimulation rates elicited a higher pitch and were perceived as less dull than lower rates. CONCLUSION: A high rate of stimulation resulted in better speech recognition in both strategies and a favorable subjective sound quality for FS4 in all tested settings.
Subject(s)
Cochlear Implants , Deafness/surgery , Adult , Aged , Cochlear Implantation , Cross-Over Studies , Double-Blind Method , Female , Humans , Male , Middle Aged , Speech Perception/physiologyABSTRACT
OBJECTIVES/HYPOTHESIS: The aim of this study was to evaluate functional hearing gain, speech understanding, and preoperative bone-conduction thresholds with the bone-conduction implant Bonebridge. STUDY DESIGN: Retrospective study at a tertiary referral center. METHODS: Twenty-four consecutive Bonebridge patients were identified. Nine patients suffered from combined hearing loss (HL), 12 from atresia of the external auditory canal and three from single-sided deafness. One patient was lost to follow-up. Twenty-three patients were therefore analyzed. RESULTS: The overall average functional hearing gain of all patients (n = 23) was 28.8 dB (±16.1 standard deviation [SD]). Monosyllabic word scores at 65 dB sound pressure level in quiet increased statistically significantly from 4.6 (±7.4 SD) percentage points to 53.7 (±23.0 SD) percentage points. Evaluation of preoperative bone-conduction thresholds revealed three patients with thresholds higher than 45 dB HL in the high frequencies starting at 2 kHz. These three patients had a very limited benefit of their bone-conduction implants. CONCLUSIONS: The Bonebridge bone-conduction implant provides satisfactory results concerning functional gain and speech perception if preoperative bone conduction lies within 45 dB HL. LEVEL OF EVIDENCE: 4.
Subject(s)
Bone Conduction/physiology , Hearing Aids , Hearing Loss, Conductive/surgery , Prosthesis Implantation/methods , Speech Perception/physiology , Adolescent , Adult , Aged , Aged, 80 and over , Audiometry, Pure-Tone , Auditory Threshold , Child , Female , Follow-Up Studies , Hearing Loss, Conductive/physiopathology , Humans , Male , Middle Aged , Prosthesis Design , Retrospective Studies , Suture Anchors , Suture Techniques/instrumentation , Treatment Outcome , Young AdultABSTRACT
OBJECTIVES/HYPOTHESIS: To evaluate modified coupling techniques of the Vibrant Soundbridge system in patients with mixed and conductive hearing loss and to compare it with conventional vibroplasty. STUDY DESIGN: Retrospective study. METHODS: Two different groups were evaluated: 1) nine cases of conventional incus vibroplasty in comparison with 2) nine patients with modified coupling of the floating mass transducer. In the modified coupling approach, the vibrant floating mass transducer was attached to 1) the stapes/oval window, 2) the round window, or 3) the drilled promontory bone (promontory fenestration window). In three patients, an additional ossiculoplasty was performed. Preoperative and postoperative aided and unaided pure-tone and free-field audiometry and Freiburg monosyllabic word test were used to assess hearing outcome. RESULTS: Functional hearing gain obtained in patients with mixed and conductive hearing loss who underwent modified coupling was 39 dB. Patients with pure sensorineural hearing loss who received conventional incus coupling showed a functional hearing gain of 25 dB. Average functional gain was 41 dB in the oval window group, 45 dB in the round window group, and 30 dB in the promontory fenestration window group. Word recognition test revealed an average improvement of 51% and 21% in the modified and in the conventional approach, respectively. CONCLUSIONS: Modified vibroplasty is a safe and effective treatment for patients with conductive and mixed hearing loss. Coupling the floating mass transducer to the promontory bone (promontory fenestration window) is a viable option in chronically disabled ears if oval and round window coupling is not possible. LEVEL OF EVIDENCE: 4.
