Insertion Trauma Rate Lower in Lateral Wall Arrays Than Perimodiolar Arrays Following Cochlear Implantation

by Linda Kossoff •

How do lateral wall (LW) and perimodiolar (PM) electrode arrays compare with respect to potentially trauma-inducing scalar translocation (STL) in cochlear implants (CI)?

BOTTOM LINE

LW arrays are preferable to PM arrays for minimizing clinically relevant intracochlear trauma in cochlear implantation.

BACKGROUND: The two distinguishable types of electrode arrays used in cochlear implantation are LW and PM. Postoperatively, STL of the electrode array may occur, causing intracochlear trauma and negatively affecting patient’s hearing performance. Therefore, it is relevant to compare the performances of LW and PM arrays in terms of STL.

STUDY DESIGN: Systematic review.

SETTING: Department of Otorhinolaryngology–Head & Neck Surgery, University Medical Center Utrecht, Utrecht University, The Netherlands.

SYNOPSIS: Researchers conducted a systematic search for postoperative CT data on the occurrence of large insertion trauma of the electrode array following CI between May 1, 2009, and June 1, 2020. Of the 2,128 unique articles retrieved, 33 were included for analysis. The baseline characteristics of the analyzed studies were extracted. The investigators also identified and conducted a meta-analysis of an STL cohort of five comparative studies to specifically compare STL rate of LW and PM arrays. The meta-analysis showed that the STL rate is significantly lower for the LW than the PM arrays (7% vs. 43%). STL occurred predominantly at 180 degrees intracochlearly. Overall, postoperative speech perception and preservation of residual hearing were found to be poorer for the cochlear implantation patients with STL compared to those without an STL. Based on this study’s findings, researchers concluded that LW arrays would be the preferred option for cochlear implantation for the current medical practice. Study limitations included a lack of randomization or standardization of surgical insertion approaches and the focus on only large insertion trauma.

Citation: Jwair S, Prins A, Wegner I, et al. Scalar translocation comparison between lateral wall and perimodiolar cochlear implant array—a meta-analysis. Laryngoscope. 2021;131:1358-1368.