Congenital sensorineural hearing loss in consanguineous marriages – Does the cochlear length vary

Abstract

Objective: There is an increased prevalence of congenital sensorineural hearing loss (SNHL) among children born out of consanguineous wedlocks, and congenital deafness is associated with increased prevalence of structural inner-ear malformations. This study is done to evaluate whether consanguinity affects the cochlear length, which in turn will influence the type of cochlear implant and depth of electrode insertion during surgery in these patients. Methods: Children presenting with congenital SNHL and born out of consanguineous marriages (Group A) were compared with children presenting with SNHL and born out of nonconsanguineous marriages (Group B). Patients in both groups were evaluated with magnetic resonance imaging as a routine pretreatment workup. A high-resolution three-dimensional T2-weighted sampling perfection with application-optimized contrasts using different flip-angle evolution imaging of the inner ears was performed. Curved multiplanar reconstruction module was used to deconvolute the membranous cochlea and measure its length. The cochlear lengths among both the groups were compared using analysis of variance test. Results: A total of seven patients were included in both Groups A and B each. The mean length of membranous cochlea in Group A was 22.6 mm and Group B was 22.5 mm. There was no statistically significant variation in the cochlear lengths of both the groups. Conclusion: Consanguinity is unlikely to produce any significant variation in the length of the cochlea.