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Objective: To assess patient-reported outcomes (PROs) in individuals with significant residual low-frequency hearing and severe-to-profound high-frequency sensorineural hearing loss (SNHL) who received the hybrid cochlear implant (CI)., Study Design: Prospective, multicenter, nonrandomized, single-arm repeated measures, single-subject design., Setting: Tertiary centers, ambulatory care., Patients: Fifty adults with severe-to-profound high-frequency SNHL and residual low-frequency hearing with aided word recognition scores between 10 and 60% in the ear to be implanted, and in the contralateral ear greater than or equal to implant ear less than or equal to 80%., Intervention: Therapeutic; hybrid CI., Main Outcome Measures: Speech, spatial and qualities of hearing scale (SSQ), device use questionnaire (DUQ), University of Washington Clinical Assessment of Music Perception (UW-CAMP) assessed preoperatively and after 6 and 12 (SSQ and DUQ only) months of hybrid CI use., Results: Significant improvements in mean SSQ ratings were demonstrated at 6 and 12 months postactivation overall and for domains related to speech hearing, spatial hearing, and sound quality. Significant improvement was also found for overall satisfaction on the DUQ and across a number of specific listening situations in addition to aspects related to social engagement. UW-CAMP pitch discrimination and melody and timbre recognition abilities were not compromised postoperatively, allowing hybrid subjects to maintain superior music perception abilities than typically observed with standard CIs., Conclusions: Patients who received the hybrid CI demonstrated significant PRO benefits on the SSQ and the DUQ after 6 and 12 months of CI use. In addition, given the opportunity to maintain useful low-frequency acoustic hearing, patients retained music listening abilities, as assessed by the UW-CAMP.

Aim: To monitor cochlear function during cochlear implantation and determine correlations with postoperative acoustic hearing., Background: Cochlear response telemetry measures cochlear function directly from cochlear implant electrodes. We have adapted this system to provide real-time cochlear response telemetry (RT-CRT) monitoring of a patient's acoustic hearing as the cochlear implant electrode array is inserted., Methods: Eighteen subjects (1 child and 17 adults) with sloping high frequency hearing loss were implanted with Cochlear Ltd slim straight arrays (CI422/CI522). Tone bursts (500 Hz, 100-110 dB) were presented at 14 Hz continuously during the array insertion. RT-CRT amplitudes were correlated with surgical manoeuvres recorded on the video from the operating microscope and with postoperative pure tone audiograms., Results: Despite an excellent overall rate of complete or partial hearing preservation (79%), RT-CRT identified that in 47% of these implantations there was transient or permanent reduction in the amplitude of the cochlear microphonic (CM). Patients with a preserved CM at the end of insertion had on average 15 dB better low-frequency hearing preservation. The CM amplitude was most vulnerable during the last few millimeters of insertion or when inadvertent movement of the array occurred after full insertion. Physical contact/elevation of the basilar membrane is hypothesized as a likely mechanism of hearing loss rather than overt physical trauma., Conclusion: RT-CRT can be used to predict early postoperative hearing loss and to potentially refine surgical technique. In the future, feedback of RT-CRT may prove to be a valuable tool for maximizing preservation of residual hearing or providing feedback on electrode contact with the basilar membrane.

Objective: This study seeks to assess the efficacy of the Envoy Esteem totally implantable hearing device in treating profound high-frequency sensorineural hearing loss., Patients: Five patients with profound high-frequency hearing loss participating in a prospective, multi-center, nonrandomized Food and Drug Administration clinical trial., Intervention: Implantation with Esteem totally implantable hearing device and comparison to baseline unaided and aided conditions., Main Outcome Measure: Speech reception threshold and word recognition scores (WRS) at 50 dB HL presentation level., Results: Preoperative speech reception threshold improved from an unaided 65 dB and aided 48 dB average to 26 dB with the Esteem at 12 months. WRS at 50 dB scores improved from an unaided 10% and aided 23% average to 78% postoperatively., Conclusion: The Esteem totally implantable middle ear hearing device provides appreciable functional gain and improvement in WRS to rehabilitate hearing in patients with a profound high-frequency sensorineural hearing loss.

Objective: To compare 2 open-ear hearing solutions for sloping high-frequency sensorineural hearing loss: open-fit hearing aid (HA) and active middle ear implant (AMEI)., Study Design: Within-subjects prospective design., Setting: Tertiary referral hospital. PATIENTS AND DEVICES: Fourteen patients with sloping, high-frequency sensorineural hearing loss were recruited from 39 patients previously implanted with an AMEI and 10 agreed to participate, ranging in age from 44 to 73 years (mean, 59 yr). Patients were selected because their hearing thresholds (500-3,000 Hz) qualified them for both AMEI and open-fit HA use. All patients received a Vibrant Soundbridge (Vibrant MED-EL) for an average of 25.1 months before data collection and used their AMEI on a daily basis. The open-fit HA used in this study was the Delta 8000 (Oticon). Both study devices have been fit with the specific fitting strategies as recommended by the manufacturer., Main Outcome Measures: Sound-field hearing thresholds, Freiburger monosyllabic words in quiet, speech reception thresholds for 50% correct recognition for Freiburger numbers and for Oldenburg sentences in quiet, and speech reception thresholds for 50% correct recognition for Oldenburg sentences in noise., Results: Both HA and AMEI conditions showed significantly better sound-field thresholds and speech recognition on monosyllabic word and sentence tests in quiet and in noise than in the unaided condition. A comparison of aided conditions revealed that, in the AMEI-aided condition, high-frequency audibility and speech discrimination scores in quiet and in noise were significantly better than those in the open-fit HA., Conclusion: Both open-fit HAs and AMEIs provided audiologic benefit to patients with sloping high-frequency sensorineural hearing loss. However, despite overlapping indication criteria for the 2 devices, performance with the AMEI was significantly better for the AMEI than for the open-fit HA.

Objective: To substantiate the benefits of hybrid cochlear implantation (CI) in patients with residual low-frequency hearing., Study Design: Prospective study of patients in a manufacturer-sponsored clinical trial., Setting: Independent referral center for CI., Patients: Thirteen patients who met candidacy criteria for a hybrid CI. The 10 women and 3 men had a mean age of 51 years., Intervention: Preoperative evaluation, CI with a Nucleus Hybrid cochlear implant, subsequent programming, and diagnostic testing., Main Outcome Measures: Benefits of high-frequency electrical stimulation from the hybrid CI as measured by conventional audiometry, consonant-nucleus-consonant monosyllabic word and Bamford-Kowal-Bench sentence in noise testing at quarterly intervals per protocol., Results: Follow-up ranged from 3 to 24 months. All 13 patients had preserved hearing immediately postoperative. However, one lost residual hearing 7 days postoperatively, and 2 patients had delayed hearing losses at 2 and 24 months, the latter apparently due to barotrauma; however, this was not conclusive. Another had a bilateral symmetrically progressive hearing loss. Six patients showed changes in low-frequency hearing less than 10 dB; 2 showed changes in the range 11 to 20 dB; 2, 21 to 30 dB; and 3, more than 50 dB. Eleven of 13 had improved consonant-nucleus-consonant words ranging up to 83% when tested with hearing aid + CI in the operated ear. Four subjects exhibited improvement in Bamford-Kowal-Bench sentence in noise testing, although only one subject showed a significant decline associated with bilateral progression in hearing impairment., Conclusion: Combined electrical and acoustical hearing can result in significant improvement in speech understanding. Only one patient lost residual hearing as a direct result of surgery. Two others had delayed losses. There are no absolute predictive factors as to success with hybrid CI, just as there are none for conventional CI. Similarly, wide variation in results may occur. Further studies may clarify factors involved in such variation.

Existing mechanical and acoustic models of the human middle ear are used to investigate the expected performance of various middle ear reconstructive procedures. Although the results of these analyses generally are consistent with observed surgical results, such an analytic approach enables the formation of some simple rules for maximizing middle ear function after stapedectomy and tympanomastoid surgery. Model analyses predict the following: (1) stapes prostheses of 0.6 to 0.8 mm in diameter produce air-bone gaps of less than 12 dB; smaller diameter prostheses produce larger air-bone gaps; (2) the mass of a stapedectomy or ossicular replacement prosthesis can be 16 times greater than that of the stapes with little effect on the hearing result; (3) the volume of the middle ear air spaces after tympanomastoid surgery should be at least 0.5 cc for optimal acoustic results; and (4) in a type IV tympanoplasty, the effectiveness of the round window graft (acoustic shield) is an important parameter determining the hearing result; the shield should be as impedant (stiff) as possible for optimal postoperative hearing. The model framework described in this report hopefully can be used to investigate the effect of variations in other surgical and help define new procedures.

The histopathologic consequence of removing and reimplanting intracochlear electrode arrays on residual auditory nerve fibers is an important issue when evaluating the safety of cochlear prostheses. The authors have examined this issue by implanting multichannel intracochlear electrodes in macaque monkeys. Macaques were selected because of the similarity of the surgical technique used to insert electrodes into the cochlea compared to that in humans, in particular the ability to insert the arrays into the upper basal turn. Five macaques were bilaterally implanted with the Melbourne/Cochlear banded electrode array. Following a minimum implant period of 5 months, the electrode array on one side of each animal was removed and another immediately implanted. The animals were sacrificed a minimum of 5 months following the reinsertion procedure, and the cochleas prepared for histopathologic analysis. Long-term implantation of the electrode resulted in a relatively mild tissue response within the cochlea. Results also showed that inner and outer hair cell survival, although significantly reduced adjacent to the array, was normal in 8 of the 10 cochleas apicalward. Moreover, the electrode reinsertion procedure did not appear to adversely affect this apical hair cell population. Significant new bone formation was frequently observed in both control and reimplanted cochleas close to the electrode fenestration site and was associated with trauma to the endosteum and/or the introduction of bone chips into the cochlea at the time of surgery. Electrode insertion trauma, involving the osseous spiral lamina or basilar membrane, was more commonly observed in reimplanted cochleas. This damage was usually restricted to the lower basal turn and resulted in a more extensive ganglion cell loss. Finally, in a number of cochleas part of the electrode array was located within the scala media or scala vestibuli. These electrodes did not appear to evoke a more extensive tissue response or result in more extensive neural degeneration compared with electrodes located within the scala tympani. In conclusion, the present study has shown that the reimplantation of a multichannel scala, tympani electrode array can be achieved with minimal damage to the majority of cochlear structures. Increased insertion trauma, resulting in new bone formation and spiral ganglion cell loss, can occur in the lower basal turn in cases where the electrode entry point is difficult to identify due to proliferation of granulation and fibrous tissue.