Clinical Analysis of Techniques and Complications in 414 Consecutive Cochlear Implantations

Abstract

Aim: To report the frequency of surgical complications following 414 consecutive cochlear implant surgeries (402 children; 12 adults), of whom 323 underwent standard incision and 91 minimal access incision and to analyze the feasibility of using the minimal access approach in all CI candidates. A careful assessment was performed to analyze whether the latter approach is more advantageous than the former in different quality parameters.
Methods: Retrospective analysis of patients who underwent cochlear implant surgery from February 2012 to February 2019 by the same surgeon at a single center.
Patients: 414 consecutively implanted patients (male: 51.33% female: 49.33%, Right: 68.66% Left: 26.66%, Bilateral: 4.66%).323 underwent a standard incision (Lazy S) and 91 underwent a minimal access incision. The average age of the standard incision group was 4.3years (range 9months-73years); that of the minimal access group 8.6 years (Range 9months-64years). The average incision size in the standard incision group was 7.61 cm and that of the minimum access group was 4.53cm.
Results: Of the 414 patients who underwent surgery there were 30 surgery related complications (12 major, 18 minor), 11 device related complications. Major complications (5.3%) included wound infection (3); device extrusion (1); electrode displacement (2); temporary CSF leak (5) (in patients with cochleovestibular dysplasia’s); magnet displacement (1). The minor complications included transient facial paresis (3); vertigo (2); seroma (9); hematoma (1); tinnitus (3). There were 11 device failures, one secondary to trauma the overall complication rate (9.6%) was low in our center when compared against available literature
The mean operative time was 76 minutes for standard incision and 79.5minutes for the minimal access approach. A counter sink well for the receiver stimulator array was created and tie down of the device was done in all patients irrespective of the incision, except when a thin implant was used.
Clinical Significance: Cochlear implantation is a low-risk procedure when performed by an experienced surgeon following standard protocol. Detailed preoperative workup, study of access and tailoring of the approach to suit each patient is a necessity to prevent complications. The minimal access incision causes less morbidity, is cosmetically more acceptable to patients and offers sufficient access to perform a cochlear implantation without compromising on vital steps.