FIRST EXPERIENCE WITH THE COMBI 40 COCHLE AR IMPLANT - SURGICAL ASPECTS

The rehabilitation of profoundly deaf patients by means of cochlear im plants has become a well established form of therapy. Recently,large s cale studies have pointed out a variety of surgical complications. A m ultiplicity of new implant types are each placing more specific demand s on the surgeons. Based on the experience with about 160 cochlear imp lantations in total,the most suitable surgical technique for the impla ntation of the Combi 40 cochlear implant which has been used in 41 cas es is presented. An extended retroauricular incision is made and a cau dally based flap is fashioned. The implant bed is drilled 0.5-1 cm beh ind and above the mastoid cavity. Between the implant bed and the mast oid cavity a groove for the electrodes is drilled cranial of the impla nt site in the right ear and caudal in the left ear. Access to the sca la tympani is gained by a promontory cochleostomy via a posterior tymp anotomy of 2x3 mm. Videocontrolled microendoscopes are used to inspect the scala tympani prior to electrode insertion. Electrode insertions depths of up to 30 mm are usually achieved. The electrode and the impl ant are secured with ionomer-based cement. The described technique has up to now been successfully performed in 30 adults and 11 children.