Veria operation updated. I. The trans-canal wall cochlear implantation.

The Veria operation is a non-mastoidectomy technique for cochlear implantation. It uses the transcanal approach to the middle ear and the cochlea. The steps of the procedure are: (1) endaural approach, that offers a wide accessibility to the middle ear structures; (2) inspection of the middle ear anatomy; (3) straightening of the postero-superior bony canal wall, which is usually concave; (4) performing the cochleostomy through the outer ear canal; (5) drilling of the suprameatal hollow, which is used for the accommodation of the electrode excess; (6) drilling of the trans-wall direct tunnel, which is the pathway for the active electrode; (7) alignment of the direct tunnel to the cochleostomy; (8) extension of the incision and preparing of the flaps; (9) creating of the bed and fixing the device; (10) insertion of the electrodes; (11) manipulating the excess of the active electrode, and (12) closing. For this technique, two special instruments have been developed: a special perforator used for the drilling of the direct tunnel for the active electrode, making it completely safe, and a safety electrode forceps used to manipulate the active electrode during insertion. The direct tunnel can be enlarged superiorly permitting insertion of two electrodes, in cases where a double electrode array implant has to be used. The method is an efficient tool for handling all cochlear implant cases, including difficult ones such as revision cases, malformations, cochlear ossifications and poor mastoid development. It is safe without complications in over a hundred cases and easy to learn.