■ OBJECTIVES: Evolution of the surgical techniques for the cochlear implantation finds the reflection in the elaboration of a number of accesses to the cochlea, which are used in the process of operation by specialists. Now together with the classical mastoidotympanotomy the suprameatal, pericanal, transcranial (via the middle fossa), transcanal, parameatal accesses are applied. At the same time the presence of various suggested surgical accesses presupposes their imperfection. Beginning from 2005 on the base of Military-Medical Academy and the Institute of Ear, Throat, Nose and Speech we elaborated and experimentally proved quite a new approach to cochlea, which was introduced into clinical practice for cochlear implantation for children and adults.

■ METHODS: There were preliminary elaborated the surgical techniques of the method on 10 isolated temporal bones of adults. Later there was carried out the mentioned method of cochlear implantation on 7 patients (6 children at the age of 2-8 years and 2 adults). The access was carried out through the small (5-6 cm) incision behind the ear with moving aside the mild tissues and periosteum and creating the back pouch for the implant in the parieto-occipital region. After endoaural tympanotomiy the cochleostoma in a typical point of the basal cochlear cure was made. The antrum was opened transmastoidally, the aditus was dilated and the lateral wall was thinned. Its anterior-inferior wall was extracted up to turning of the horizontal part of facial nerve to vertical part. The incus-stapedial joint was dissected by “Twiner Erbium YAG”-laser and the incus was removed. After positioning and fastening of the implant the active electrode was inserted along the bottom of aditus (under the double control from the latter and cavum tympani) into the cochleostoma.

■ RESULTS: The transaditoantral method did not excess 1,5-2 hours. There were well visible the horizontal semicircular canal, the aditus bottom, the horizontal and beginning of vertical parts of bone canal of the facial nerve, the incus, the stapes and the cochleostoma during the operation. Technical difficulty during introduction of the electrode was noted in a child of 4 years old with the rotation of cochlea backwards (right ear). There were no complications in the postoperative period. According to x-ray images of temporal bones by Stenvers (5 patients) and KT (3 patients) the active electrode was placed in cochlea. The hearing and speech rehabilitation of all implanted patients was successful.

■ CONCLUSIONS: The proposed transaditoantral surgical access for cochlear implantation is technically simple and safe method, which permit to visualize and avoid collisions with the most delicate zones of middle ear. The incus extraction excludes the appearance of possible distortion of hearing perception, which might be due to function of the liquid substances and mild tissues of inner ear, and prevents the forming of the occlusion between aditus and cavum tympani, which might be as a result of introduction of the alien body (electrode) into a middle ear. When we have the retrovert cochlea it is expedient to form the cochleostoma somewhere ahead of the classical position with the maximal deepening (careful) the bottom of aditus. This access practically does not hurt the chorda tympani and the facial nerve.