Hearing Rehabilitation in Congenital Middle Ear Malformation

Microtia and atresia cause significant conductive hearing loss of up to 60 dB HL. The bilateral cases suffer from severely restricted communication abilities and require immediate acoustic stimulation. There is also growing evidence that unilateral cases benefit from an early and selective stimulation of the affected side. Hearing restoration can be performed in selected cases of minor malformation by classic middle ear reconstruction. However, the majority of patients presumably benefit better from a hearing aid. There are 3 main types: active middle ear implants, active bone conduction implants and passive bone conduction implants. All implants improve speech perception, speech recognition, the signal-to-noise ratio and directional hearing. The extent varies among implants and requires further studies. Decision making on the implant type depends on the extent of malformation and hence the preoperative imaging. New scoring systems provide reliable risk stratification. Second it depends on the age of the patient. The active middle ear implants provide a selective stimulation of the affected side and are beneficial if implanted in the first years of life during the maturation period of the auditory system. In conclusion, hearing rehabilitation of congenital atresia should be performed as early as possible. This includes not only the bilateral but also the unilateral affected patients.