Stéphane Tringali

European results with totally implantable carina placed on the round window: 2-year follow-up.

Objectives: First, to assess for the performance of the Carina placed on the round window at various European centers; second, to study the follow-up after 2 years and discuss limitations and technical issues; and finally, to further develop our understanding of the principles of acoustic transfer through the round window. Materials and Methods: Eleven patients were included in this retrospective study (7 women and 4 men) from 7 European tertiary referral hospitals (4 centers in France, 2 in Belgium, 1 in Spain). The mean age was 50.8 years (35-71 yr). All patients have multiple previous surgeries (>3 surgical procedures) for otosclerosis (3 patients) or chronic otitis media (8 patients), and in all cases, the stapes was not accessible due to obliteration by sclerotic tissue. Preoperative and postoperative air conduction, bone conduction, as well as aided and unaided thresholds and speech scores were measured. Results: No significant differences were observed between preoperative and postoperative air-conduction and bone-conduction pure-tone averages. The average free field functional gain obtained with the implant ranged from 22 to 42 dB at each individual frequency, with a mean of 29 ± 5 dB across all audiometric frequencies. Word recognition scores demonstrated significant differences between unaided and implant-aided conditions. Complications included 2 cases of postoperative infection (including 1 anacusis) that required explantation, and 1 case reduced initial benefit, followed by a nonfunctioning device. In 10 patients, postoperative hearing was unchanged. The 8 other patients are using their implant daily. Conclusion: These results show that this option is valid for patients with a fixed footplate and unsuccessful previous surgeries or patients who cannot benefit from a stapedotomy for anatomic reasons. In some cases, access to the round window membrane could represent a limitation. However, these promising initial results establish the need for further works with regard to 3 issues: 1) clinical data studies are needed, including a greater number of patients to confirm these preliminary results; 2) a long-term follow-up must be performed to detect any possible cochlear adverse effects, in particular, on the basilar membrane; 3) the effect of fascia interposition and tip size has to be evaluated in experimental studies.

Prospective study of positional nystagmus in 100 consecutive patients.

Objectives: The purpose of this study was to investigate the various diagnoses of patients who present with positional nystagmus. Methods: Positional maneuvers were systematically performed in the plane of the posterior canal (PC; Dix-Hallpike maneuver) and the horizontal canal (HC; patients were rolled to either side in a supine position) on 490 consecutive patients essentially referred for vertigo and/or gait unsteadiness. Results: One hundred patients (20%) presented positional nystagmus. This nystagmus had a peripheral origin in 83 patients, including 80 patients with benign paroxysmal positional vertigo (BPPV). In BPPV, the PC was involved in 61 patients, the HC in 18 patients (geotropic horizontal nystagmus in 11 and ageotropic in 7; changing from geotropic to ageotropic or the reverse in 4 patients), and both the PC and HC in 1 patient. There was evidence of central positional nystagmus in 12 patients, including positional downbeat nystagmus during the Dix-Hallpike maneuver in 7 patients with various neurologic disorders, and ageotropic horizontal nystagmus during the HC maneuver in 2 patients with, respectively, cerebellar ischemia and definite migrainous vertigo. The peripheral or central origin of the positional nystagmus could not be ascertained in 5 patients, including 1 patient with probable migrainous vertigo and another with possible anterior canal BPPV. Conclusions: A rotatory-upbeat nystagmus in the context of PC BPPV, a horizontal nystagmus, whether geotropic or ageotropic, due to HC BPPV, and a positional downbeat nystagmus related to various central disorders are the 3 most common types of positional nystagmus. Geotropic horizontal positional nystagmus and, most certainly, horizontal positional nystagmus changing from geotropic to ageotropic or the reverse point to HC BPPV. In contrast, an ageotropic horizontal positional nystagmus that is not changing (from ageotropic to geotropic) may indicate a central lesion.

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.

Round Window Membrane Implantation with an Active Middle Ear Implant: A Study of the Effects on the Performance of Round Window Exposure and Transducer Tip Diameter in Human Cadaveric Temporal Bones

Objectives: To assess the importance of 2 variables, transducer tip diameter and resection of the round window (RW) niche, affecting the optimization of the mechanical stimulation of the RW membrane with an active middle ear implant (AMEI). Materials and Methods: Ten temporal bones were prepared with combined atticotomy and facial recess approach to expose the RW. An AMEI stimulated the RW with 2 ball tip diameters (0.5 and 1.0 mm) before and after the resection of the bony rim of the RW niche. The RW drive performance, assessed by stapes velocities using laser Doppler velocimetry, was analyzed in 3 frequency ranges: low (0.25–1 kHz), medium (1–3 kHz) and high (3–8 kHz). Results: Driving the RW produced mean peak stapes velocities (HEV) of 0.305 and 0.255 mm/s/V at 3.03 kHz, respectively, for the 1- and 0.5-mm tips, with the RW niche intact. Niche drilling increased the HEV to 0.73 and 0.832 mm/s/V for the 1- and 0.5-mm tips, respectively. The tip diameter produced no difference in output at low and medium frequencies; however, the 0.5-mm tip was 5 and 6 dB better than the 1-mm tip at high frequencies before and after niche drilling, respectively. Drilling the niche significantly improved the output by 4 dB at high frequencies for the 1-mm tip, and by 6 and 10 dB in the medium- and high-frequency ranges for the 0.5-mm tip. Conclusion: The AMEI was able to successfully drive the RW membrane in cadaveric temporal bones using a classical facial recess approach. Stimulation of the RW membrane with an AMEI without drilling the niche is sufficient for successful hearing outputs. However, the resection of the bony rim of the RW niche significantly improved the RW stimulation at medium and higher frequencies. Drilling the niche enhances the exposure of the RW membrane and facilitates positioning the implant tip.

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.

Combined horizontal and posterior canal benign paroxysmal positional vertigo in three patients with head trauma.

We report 3 patients who complained of positional vertigo shortly after head trauma. Positional maneuvers performed in the plane of the posterior canal (PC; Dix-Hallpike maneuver) and the horizontal canal (HC; patients were rolled to either side in a supine position with the head raised 30°) revealed a complex positional nystagmus that could only be interpreted as the result of combined PC and HC benign paroxysmal positional vertigo (BPPV). Two patients had a right PC BPPV and an ageotropic HC BPPV, and 1 patient had a bilateral PC BPPV and a left geotropic HC BPPV. All 3 patients were rapidly free of vertigo after the PC BPPV was cured by the Epley maneuver and the geotropic HC BPPV was cured by the Vannucchi method. The ageotropic HC BPPV resolved spontaneously. Neuroimaging (brain computed tomography and/or magnetic resonance imaging scans) findings were normal in all 3 patients. From a physiopathological viewpoint, it is easy to conceive that head trauma could throw otoconial debris into different canals of each labyrinth and be responsible for these combined forms of BPPV. Consequently, in trauma patients with vertigo, it is mandatory to perform the Dix-Hallpike maneuver, as well as supine lateral head turns, in order to diagnose PC BPPV, HC BPPV, or the association of both. Early diagnosis and treatment of BPPV may help to reduce the postconcussion syndrome.

A pilot study of the safety and performance of the Otologics fully implantable hearing device: transducing sounds via the round window membrane to the inner ear.

Objectives: The safety and performance of the Otologics fully implantable hearing device were assessed in adult patients with mixed conductive and sensorineural hearing loss. Methods: The subcutaneous microphone of this fully implantable device picks up ambient sounds, converts them into an electrical signal, amplifies the signal according to the user’s needs, and sends it to an electromechanical transducer. The transducer tip is customized with a prosthesis in order to be in contact with the round window membrane and is protected by fascia; this translates the electrical signal into a mechanical motion that directly stimulates the round window membrane and enables the user to perceive sound. The implanted battery is recharged daily via an external charger and the user can turn the implant on and off as well as adjust the volume with a hand-held remote control. In this pilot study, 6 patients with mixed conductive and sensorineural hearing loss were implanted with the Otologics fully implantable hearing device. Pre- and postoperative air conduction, bone conduction, as well as aided and unaided thresholds and speech scores were measured. Results: No significant differences between preoperative and postoperative pure-tone averages were noted. Average improvement ranged from 19.16 to 35.8 dB of functional gain across audiometric frequencies with a mean of 26.17 ± 5.15 dB. Long-term average functional gain at 12 months was 20.83 ± 6.22 dB. Word recognition scores demonstrated significant differences between unaided and implant-aided conditions. Conclusions: Preliminary results of this trial of the Otologics fully implantable hearing device provide evidence that this fully implantable device is capable of efficiently transferring the sound to the inner ear via the round window membrane in patients with mixed hearing loss.

Strategies of active middle ear implants for hearing rehabilitation in congenital aural atresia.

Objective: To describe our surgical and audiometric experience using different active middle ear implant strategies facing various anatomic situations in aural atresia. Study Design: Retrospective case review. Setting: Tertiary academic referral center. Patients: Five patients with congenital aural atresia, (3 unilateral and 2 bilateral), with mean age of 22.4 years (range, 12-44 yr), referred for hearing rehabilitation. Intervention: Active middle ear implant on stapes capitulum. Main Outcome Measures: Description of surgical implantation with different active middle ear implants. Preoperative and postoperative air conduction, bone conduction, and aided and unaided thresholds and speech scores were measured, at mid to long term. Subjective benefit analysis was determined through the Abbreviated Profile of Hearing Aid Benefit questionnaire. Results: After activation and fitting of the devices, a mean functional gain of 32.5 dB hearing level was measured. Speech tests in quiet showed a mean functional gain of 20.2 dB. Patients had a mean follow-up period of 12 months. No intraoperative or postoperative complications were noted. Furthermore, we reflected on new coupling possibilities, especially in a difficult case with stapes-footplate fixation where no approach of the round window was feasible because of aberrant facial nerve course. Conclusion: Facing anatomic variations in congenital aural atresia, active middle ear implants can provide substantial hearing improvement in safe conditions and open new strategies for hearing rehabilitation.

Active middle ear implant application in case of stapes fixation: a temporal bone study.

Hypothesis: Driving the oval window directly with an active middle ear implant (AMEI) can produce high levels of input to the inner ear. Background: Treatment of otosclerosis bypasses the stapes with a piston that penetrates the vestibule. Although this treats the conductive component of hearing loss, it does not treat the sensorineural part, which can be improved using an additional conventional hearing aid. Active middle ear implants have been proposed to be an alternative in treating otosclerosis in cases of mixed hearing losses. Methods: Seven temporal bones were prepared to expose the stapes and round window (RW). Stapes and RW velocities were measured while driving with an AMEI the stapes head with a bell-shaped tip. The stapes footplate was then fixed with acrylic cement; fixation was confirmed through attenuated RW velocities. A cylinder tip (0.5 mm) was then used to drive the inner ear through a stapedotomy with and without interposition of fascia. Results: Driving the stapes with an AMEI produced mean maximum equivalent ear canal sound pressure levels (SPL) of 138 dB (0.25-8 kHz at 1 V [RMS]). Stapes fixation caused a ∼25-dB attenuation. Driving with a cylinder tip through the stapedotomy produced 114 dB SPL (24 dB less than normal) and 110 dB SPL (28 dB less than normal) performance with and without fascia, respectively. Performance with fascia was greater than without. Conclusion: Driving the oval window with an AMEI in a scenario of stapes fixation was demonstrated to be feasible, with performance comparable to traditional AMEI coupling to the incus or stapes. These possibilities offer new perspectives to treat mixed hearing loss in case of fixed footplate.