Early Clinical Results of the Eestem System, a Totally Implantable Middle Ear Device, for Sensorineural Hearing Loss

In the past decade there has been a tremendous evolution in middle ear implants for patients with sensorineural hearing loss. This report presents our experience with the fully implantable Eestem device (Envoy Medical). The Eestem implant is a piezoelectric device that amplifies sound by vibrating when electric current is passed through its ceramic disc. The tympanic membrane serves as the microphone.

Study Design: In an international multicenter study, 6 patients were operated at our institution. All patients had complete audiological workups before implantation with and without conventional hearing aids. After activation of the device the audiological results were compared to the preoperative results. In addition, questionnaires were used to assess subjective results of the patients.

Results: All patients except one showed marked improvement of their hearing ability in quiet and in high background noise levels and would repeat the implantation.

Conclusion: Although a complicated and delicate surgery is required, it could be shown that the Eestem is a functional fully implantable hearing device that can improve the results of conventional hearing aids—avoiding all their disadvantages.