Fully implantable Otologics MET Carina^™device for the treatment of sensorineural and mixed hearing loss: Audio-otological results

Abstract

We did not record any surgical relevant complication in any of the patients, nor any significant postoperative variation in hearing thresholds, for air conduction or bone conduction, indicating the absence of surgical damage to the cochlea. All the patients demonstrated improvements in speech perception abilities with the device functioning and reported subjective benefits. With regard to the postoperative adverse effects, we had problems with feedback noise, which resolved with minor fitting adjustments in seven cases, while it required a second surgery to change the microphone position in the other patient. In one case a minimal extrusion of the microphone cable occurred requiring a revision surgery, a device failure occurred in one case, requiring substitution, and one patient decided on explantation of the device owing to psychological problems.

Implantable Hearing Devices

“…Otologics later updated the MET to a fully implanted hearing device named Carina for use in adults with moderate to severe sensorineural hearing loss, which later received a CE Mark in Europe for use in conductive and mixed hearing losses [22,23]. Because of the flexibility of the internal components, Carina candidacy can encompass patients that have certain middle-ear anomalies, which would have excluded them from the Envoy Esteem implantable hearing aid [22].…”

“…The microphone placement can be in the temporalis region, the retroauricular region, or on the mastoid tip, avoiding areas that are prone to tissue thickness changes and contraction effects of the temporalis and sternocleidomastoid muscles [26,27]. Just as there are many available transducer tips, there are also many configurations for transducer placement.…”

“…Just as there are many available transducer tips, there are also many configurations for transducer placement. Reports of transducer placement have included mounting directly onto the incus, into a hole drilled into the body of the incus, at other ossicular sites including the footplate of the stapes, and at the round window membrane [21,23,[26][27][28]. Efficient coupling is important at the transducer site to prevent unnecessary battery drain, achieve appropriate gain, and avoid additional hearing loss [27,28].…”

“…There are multiple transducer types with the selection of a transducer type dependent on where the transducer is to be placed, determined by the patient's middle ear anatomy [26,27]. The receiver coil allows for transcutaneous programming of the device and recharging of the battery.…”

Wireless charing pillow for a fully implantable hearing aid: Design of a circular array coil based on finite element analysis for reducing magnetic weak zones

“…Recent research trends have focused on a full implant with a microphone and battery [3]. Most fully implantable hearing aids are completely implanted beneath the skin of the temporal bone except for the output transducer [4,5]. Thus, wireless power transmission is required for periodic battery charging.…”