Implantability of endaurally insertable active vibratory middle-ear implants - an anatomical study.

Hearing loss is often treated with an acoustic hearing aid. However, distortion and insufficient gain may cause problems. Active non-acoustic vibratory middle-ear implants (AMEI) may contribute to solve this problem. We recently developed an AMEI which is to be implanted completely through the patient's external auditory canal. The device uses a light-emitting diode (LED) in the external auditory canal that stimulates a photovoltaic sensor, placed in the middle ear, through the intact tympanic membrane. This results in activation of a vibratory miniaturized piezoelectric displacement transducer (MDT) (actuator) coupled to the auditory organ. The aim of this study was to evaluate the anatomical implantability of the novel AMEI using an exclusively endaural approach. The internal components of our AMEI were implanted into 39 human temporal bones. The surgical procedure and the optimal size and anatomical fitting were systematically evaluated. We can show here that implantation of all components of this novel AMEI into anatomical specimens proves to be a quick and easy procedure, performed using an endaural approach. The anatomical data of this study establish the basis for further technical development of our AMEI and other future implantable hearing systems.