Standard Practice for Describing System Output of Implantable Middle Ear Hearing Devices

Importancia y uso:

5.1 IMEHDs are alternatives to air conduction hearing aids. They are similar to air conduction hearing aids in that they process incoming sound by applying frequency shaping and compression to create an analog, vibratory audio frequency output. IMEHDs differ from hearing aids in that they do not create an airborne acoustical output signal with an electroacoustical output transducer in the external ear canal, but rather a mechanical stimulation that results in the vibration of the cochlear fluid. Therefore, the IMEHD output signal is not readily accessible after implantation in the way hearing aid output is accessible with real-ear probe microphone measurements. Different devices will use different methods of coupling to the ossicular chain or cochlea. This makes it difficult to design a uniform model of the middle ear in the way the 2-cm³ coupler is used as a model of the external ear canal with conventional hearing aids.

5.2 This practice provides uniformity of data collection practices, thus allowing IMEHD in vitro performances to be evaluated and readily compared. Once clinical data are available, the performance specifications can be augmented with corresponding transfer functions or results from measurements in patients.

5.3 The temporal bone is a well-accepted model that relates closely to the biomechanics of the living middle ear, which is readily relatable to hearing level. Laser Doppler vibrometry provides accurate velocity measurements in the ranges required for human hearing.

Subcomité:

F04.31

Volúmen:

13.02

Número ICS:

11.180.15 (Aids for deaf and hearing impaired people)

Palabras clave:

electromechanical hearing; hearing implant; IHD; IMEHD; implantable hearing aid; implantable middle ear hearing device; laser interferometry; middle ear; middle ear implant; system output; system performance; temporal bone; transfer function; vibrational transducer; vibratory implant;