Christian Dubreuil

Hearing rehabilitation in congenital aural atresia using the bone-anchored hearing aid: audiological and satisfaction results

Abstract Conclusion: The BAHA (bone-anchored hearing aid) remains the most reliable method of auditory rehabilitation for patients with congenital aural atresia and improves hearing outcome and quality of life in these patients who are otherwise unable to benefit from traditional hearing aids. New techniques are being developed, such as fully implantable hearing devices, and will have to prove their efficacy and safety in this indication. Objective: To evaluate the audiological results and patient satisfaction after rehabilitation of congenital aural atresia using the BAHA. Methods: Sixteen patients suffering from bilateral congenital aural atresia were implanted with unilateral BAHA. Preoperative air- and bone-conduction thresholds and air–bone gap (ABG), preoperative sound reception threshold (SRT), postoperative aided thresholds, implantation complications, patient satisfaction, and the APHAB questionnaire were collected. Results: After a mean follow-up period of 6.5 years, 15 patients were still using their device. Each patient had an average improvement of 33 ± 7 dB. Closure of the ABG within 15 dB of the preoperative bone-conduction thresholds occurred in 10 patients. Adverse skin reactions appeared in 50% of patients over 6.5 years of follow-up. Eleven of the 12 patients used their BAHA for more than 8 h per day.

Fully implantable hearing device with transducer on the round window as a treatment of mixed hearing loss

OBJECTIVE To demonstrate the safety and efficacy of the Otologics Carina Middle Ear Transducer for treatment of mixed hearing loss through a case report. METHODS A Carina fully implantable device with the MET transducer for conductive applications was implanted in a 48-year-old woman suffering from right mixed hearing loss (mean PTA loss: 80 dB). A facial recess approach was used to access the middle ear. Sclerotic tissue obliterated the stapes footplate so the approach selected was to place the transducer directly on the round window. The mounting bracket was placed on the mastoid and the prosthesis was advanced toward the round window until the Otologics surgical software indicated contact. Effective stimulation of the cochlea was confirmed intraoperatively by ABR monitoring. RESULTS Postoperative unaided PTA thresholds were unchanged after surgery. When the implant was activated, the mean PTA functional gain was 39 dB. DISCUSSION-CONCLUSION The capability of the Carina MET Ossicular stimulator to provide appropriate gain relative to the degree of hearing loss indicates that the device offers a viable treatment option for mixed hearing loss. However, these promising initial results establish the need for future work on two fronts: (1) further studies are needed including a greater number of patients to confirm these preliminary results; (2) a long term follow-up must be carried out to detect any possible cochlear adverse effects on the cochlea, in particular on the basilar membrane.

Fully implantable hearing device as a new treatment of conductive hearing loss in Franceschetti syndrome.

The objective is to investigate a new therapeutic option for treatment of conductive hearing loss in children with Franceschetti syndrome. A Carina fully implantable device with the MET V transducer for conductive applications was implanted in a 14-year-old male suffering from bilateral conductive hearing loss (mean PTA loss: 70 dB on the right ear and 64 dB on the left ear) secondary to Franceschetti (a.k.a Treacher Collins) syndrome with bilateral agenesis of external ear canal and ossicular malformation. Postoperative unaided PTA was unchanged by the surgical procedure. When the implant was activated, mean PTA was 29 dB improved on the implanted ear. The capacity of the Carina MET ossicular stimulator to provide appropriate gain relative to the degree of hearing loss indicates that the device may be a viable treatment for children with agenesis of external auditory canal and severe malformation of the middle ear. However, these initial results need to be furthered by: (1) additional studies including a greater number of patients to confirm these preliminary results and (2) a long-term follow-up must be carried out to detect possible long-term cochlear adverse effects, in particular on the basilar membrane.

Characteristics of 629 vestibular schwannomas according to preoperative caloric responses.

Objectives: To assess the contribution of preoperative caloric responses in patients with vestibular schwannoma on the following: preoperative parameters and postoperative results (facial function and hearing preservation). Study Design: Retrospective review of prospectively collected data. Setting: Tertiary referral center. Patients: A group of 629 patients who underwent vestibular schwannoma surgery. Main Outcome Measures: Caloric responses are quantified in terms of slow-phase nystagmus velocities generated during warm and cool irrigations of each ear, with asymmetry between the two horizontal semicircular canals was quantified by the Jongkees formula. When unilateral weakness (UW) was less than 20%, caloric response was regarded as normal (group N). When UW was greater than 70%, caloric response was classified as severe caloric weakness (group S), and when the UW was comprised between 70 and 20%, caloric response was classified as moderate (group M) caloric weakness (CW). Results: 47.8% of the studied patients were included in group S, 38.2% in group M, and 14% in group N. Preoperative mean hearing loss was higher in group S compared with that in groups M and N. The auditory brainstem response threshold was higher in group S compared with that in group N and also higher in group M compared with that in group N. A good correlation was observed between CW and tumor size. Postoperative facial palsy was more frequent in group S compared with groups N and M. Postoperative hearing preservation was more frequently observed in group N compared with groups S and M. Conclusion: Our results suggest that caloric responses are well correlated with the studied preoperative and intraoperative factors and provide predictive factors with regard to postoperative facial palsy and hearing outcome.

Perioperative complications after translabyrinthine removal of large or giant vestibular schwannoma: Outcomes for 123 patients

Abstract Conclusion: Large vestibular schwannomas are benign but dangerous tumors. The translabyrinthine approach allows the surgeon to limit vital and functional complications due to the disease itself or to its surgical removal. Objective: Morbi-mortality study focused on large vestibular schwannoma surgically treated by translabyrinthine removal. Methods: This was a retrospective review of prospectively collected data in a series of 123 patients who underwent translabyrinthine removal of a large vestibular schwannoma (>4 cm in the cerebellopontine angle, stage IV). All surgical and medical complications and facial function were reviewed, with a 1-year follow-up. Results: Mortality during the first year was 0.8% (one case of infarct of the anterior inferior cerebellar artery, fatal after 8 months). In all, 4.9% of patients underwent a second surgery (for delayed hemorrhage or cerebrospinal fluid leak) during the first months after removal of a large vestibular schwannoma; 3.2% of patients experienced definitive neurologic complications (one death, one cerebellar disturbance, and two cases of 10th cranial nerve palsy).

Bone-anchored hearing aid in unilateral inner ear deafness: electrophysiological results in patients following vestibular schwannoma removal

Conclusions. The results show that the healthy cochlea perceives one auditory stimulus from two auditory signals: the first through normal air conduction and the second provided by the bone-anchored hearing aid (BAHA). This artificial acoustic difference could partly explain ‘pseudo’ binaural hearing. Functional cerebral imaging using the same experimental procedure is now necessary. Objectives. The aim of this study was to evaluate electrophysiological phenomena induced by BAHA on brainstem and long-latency auditory evoked potentials (AEPs) to understand how patients recover a ‘pseudo’ binaural sensation with only one functional cochlea. Patients and methods. This prospective study included 10 patients operated via the translabyrinthine approach and who received implants on the deaf side. Electrophysiological recordings were performed at least 2 months after BAHA use. Brainstem and long-latency (N1, P2, N2, P300) AEPs were studied in free field according to four conditions: 1, without BAHA; 2, with BAHA; 3, with BAHA and normal ear occluded; 4, without BAHA and normal ear occluded. Results. For brainstem AEPs, we found significantly longer latencies of waves III and V in condition 3 compared with condition 1. For long-latency AEPs, comparison between conditions showed no significant differences.

Are stage IV vestibular schwannomas preoperatively different from other stages

Objective: The aim of this study was to focus on the clinical and paraclinical symptoms of patients suffering from Stage IV vestibular schwannomas (VSs). Patients: In this prospective study, we included 734 patients who have VS and candidates for operation. Main Outcome Measures: Patients were classified as having Stage I, II, III, or IV tumors according to Tos criteria as evaluated by magnetic resonance imaging. Preoperative Clinical Evaluation: We recorded the occurrence of complaints (%) and duration (yr) of hearing loss, tinnitus, and balance disorder. Preoperative paraclinical evaluation included pure-tone (PTA) and speech audiometry, auditory brainstem response (ABR) patterns, and vestibular deficit at videonystamography (VNG). Continuous variables were compared between Stage IV and other stages using analysis of variance. Qualitative variables expressed as a percentage of presence were compared between Stage IV and other stages using percentage comparison. Results: Quantitative Parameters. Patients with Stage IV VS were significantly younger as compared with patients with other stages. Stage IV hearing loss was greater compared with other stages at 250 and 500 Hz but smaller at 2,000 and 8,000 Hz. We found no difference in the loss of PTA between Stage IV and the other stages. Speech discriminancy score was smaller in Stage IV. The durations of hearing loss, tinnitus, and balance disorders were similar whatever the tumor stage. Auditory brainstem response patterns showed no difference in Wave III latency between Stage IV VS and other stages, whereas Wave V latency and V-I interval were higher in Stage IV. Both ABR threshold and VNG caloric deficit were higher in Stage IV VS compared with other stages. Qualitative Parameters. The percentage of patients with Stage IV was lower than that with Stages II and III. The percentage of men and women was similar in all stages. The occurrence of hearing loss was similar in all stages, whereas that of tinnitus was lower in Stage IV compared with Stages I and II. In contrast, the occurrence of balance disorder was higher in Stage IV compared with all other stages. Conclusion: In clinical and paraclinical manifestation, Stage IV VS is different from the other stages. The PTA differences may be attributed to the younger age. Occurrence of clinical symptoms, ABR, and VNG pattern can be explained by the fact that Stage IV develops rapidly in the vestibular, rather than the cochlear nerve and by the fact that larger tumors can be cerebellar compression. This has been confirmed by the higher occurrence of balance disorders in Stage IV and the lower occurrence of tinnitus with similar hearing loss in all stages.

Otologics Middle Ear Transducer With Contralateral Conventional Hearing Aid in Severe Sensorineural Hearing Loss: Evolution During the First 24 Months

Objectives: To report the audiometric outcomes of patients with severe sensorineural hearing loss and who have been fitted with a Middle Ear Transducer (MET) on one side and fitted with an optimized conventional hearing aid on the other side. Study Design: The MET fitting results were measured and compared with contralateral conventional hearing aids in a prospective study. Setting: Tertiary referral center. Patients: Seven patients (ages, 53-77 yr) with severe sensorineural hearing loss (pure-tone average, 71-90 dB HL) were implanted between December 2004 and March 2006. Method: Audiometric testing was performed the day of activation (2 mo postoperative) and after 8 days and 1, 3, 6, 9, 12, and 24 months. For each follow-up, MET and conventional hearing aid were optimized according to the patients hearing loss. Results: Mean functional gains were 29 dB for conventional hearing aid and 35 dB the first day of the study with the MET and 39 dB after 6 months. Discussion: The performance of the MET and the absence of occlusion of the external auditory canal could explain the improved benefit. For maximum gain, the MET requires a regular follow-up during the first 6 months. Conclusion: MET seems to be a suitable and successful treatment option resulting in significant improvement in speech comprehension, especially after 6 months, in patients with severe sensorineural hearing loss. During the 24-month follow-up of this study, the MET has been a safe and effective treatment for severe hearing loss.

Predictive Factors of Postoperative Facial Palsy in Acoustic Neuroma Surgery

Results Twenty-five of the 98 patients (26%) were found to have a delayed deterioration of facial function. Eleven patients had worsening of facial function that evolved in the first 5 postoperative days. Ten cases showed a deterioration within 6–13 days, while 4 patients had onset of facial dysfunction after 15 days. The incidence of delayed facial function was not influenced by age, sex, or tumor size. The majority of facial function had a favorable prognosis. Only 5 patients showed a final grades III–IV at 1 year.