人工聴覚機器の現状

Abstract

Remarkable advances have been made in the field of cochlear implantation, especially the new trends of hearing and structure preservation. Electric acoustic stimulation (EAS) is becoming a standard procedure worldwide and has improved the quality of life of patients with a ski-slope type audiogram, while Vibrant Soundbridge (VSB) and Bone Conductive Implant are also becoming available as hearing implants for the hearing-impaired population. We present the current information about hearing implants in Japan. Advances in the development of new atraumatic concepts of electrode design as well as in surgical techniques have enabled structure preservation after cochlear implantation, and EAS is a new trend for patients with residual hearing at lower frequencies, that became eligible for coverage by the national health insurance in Japan in 2014. The VSB is an active middle ear implant that was developed for the treatment of sensorineural hearing loss. Stimulation of the cochlea by coupling the small electromagnetic element called the floating mass transducer (FMT) to the round window membrane was a promising second alternative for the treatment of conductive or mixed hearing loss. A multicenter clinical study for VSB with a round window approach was conducted in Japan in 2014. Bone conductive implants allow direct transmission to the bone of the skull, and Baha is a semi-implantable percutaneous BC hearing device. A multicenter clinical study with 9 participant institutions was conducted in Japan between 2006 and 2009 to compare the efficacy of Baha with that of conventional hearing aids. Baha became eligible for coverage by the national health insurance in 2013. Several types of bone conductive implants have been developed and may be used in Japan in the near future.