Cochlear implantation in children under 4 years old Hearing loss Risk factors , Surgical considerations and Complications

Abstract

Background & Objective:. Cochlear implantation (CI) is consider as a final management for loss severe to profound and profound HL when there was no benefit from using hearing aid  and rehabilitation for 3-6  months, where It restores the patient's auditory abilities by direct stimulation of the auditory nerve fibers. CI is a common procedure that carry  some difficulties and complications. This study aims to describe surgical data in CI patients ,operation and post operation complications, results of electrophysiological implant tests  , report the HL risk factors in a group of children who underwent younger than 4  years as part of the cochlear implantation program of the Syrian Organization for Persons with Disabilities – AAMAL in Syria..

Materials and Methods : Ninety one patients were implanted during the period from 1/10/2018 till 12/31/2019 with 6 months follow - up after surgery. We Analyze HL risk factors  and report aspects of the surgical difficulties , operation and post operation complications (Early complication  within 3 weeks and delayed complications up to 6 months after surgery), Documentation of the results of the post-insertion implant (Telemetry - Auditory Nerve Response Telemetry (ART) or Neural response telemetry( NRT), and hearing thresholds  at Sound field audiometry 2-3 months after first fitting of the external processor.

Results: 91  patient : 49 male (53.84%), 42 female (46.16%) .Mean age at implantation was 31.8  months. 44 cases were implanted with Cochlear device (Cochlear company),  47 cases were implanted with MED-EL  device (MED-EL company). Within risk factors, the most common of which was consanguineous marriage. Surgical difficulties were encountered in 15 cases (16.5%) without preventing the completion of the surgery, complications during surgery were occurred in 7 cases ( 7.69%), early complications in 2 cases (2.2%), and delayed complications in 3 cases (3.3%). There were no serious complications in all cases. Reimplantation was performed to one case due to device failure after head trauma. By testing auditory responses (ART or NRT) after end of the implant insertion, only one case without getting any responses. while were recorded responses to all electrodes in  53 cases (62.35%),and no response for some electrode in the rest of cases despite the good telemetry for the electrodes . All cases reached auditory thresholds on the sound field audiometry  in the range of 30-35 dB HL within 2-3 months of the first fitting of external processor.

Conclusions: CIs are not without some difficulties and complications, but it is generally considered safe. Most of the difficulties and complications can be overcome if the implantation is carried out by an expert surgeon, with good preparation and appropriate follow-up after surgery. It is not necessary totake responses for whole electrodes and sometimes not take any response despite theabsence ofany deformation in theinner ear (Thisis common in cases ofinner ear malformations).