Volumetric Analysis of Hearing-Related Structures of Brain in Children with GJB2-Related Congenital Deafness

Abstract

Background: Children with non-syndromic hereditary sensorineural hearing loss (SNHL) provide an opportunity to explore the impact of hearing on brain development. Objective: This study investigates volumetric differences of key hearing-related structures in children with gap junction protein beta 2 GJB2-related SNHL compared to controls. Materials and methods: Ninety-four children with SNHL (n = 15) or normal hearing (n = 79) were studied using automated volumetric segmentation. Heschl’s gyrus (HG), anterior HG (aHG), planum temporale (PT), medial geniculate nucleus (MGN), and nucleus accumbens (NA) were analyzed relative to total brain volume (TBV) at two different age groups: (1) 7−12 months and (2) 13 months−18 years. Two-sided t-tests were used to evaluate differences between groups. Differences were considered significant if p < 0.007. Results: Significantly smaller aHG-to-TBV ratios were found in 13-month-to-18-year-old patients (p < 0.0055). HG-, PT-, MGN-, and NA-to-TBV ratios were smaller in the same age group, without reaching a significant level. Conversely, HG- and NA-to-TBV were larger in the younger age group. No significant differences were found between the groups for age and TBV. Conclusions: In this exploratory volumetric analysis of key hearing-related structures, we observed age-related changes in volume in children with GJB2-related SNHL.

Keywords: FreeSurfer; GJB2; Heschl’s gyrus; children; hearing loss.

Figure 1

Anatomical structures used in the FreeSurfer analysis overlaid on a coronal reformat of the T1-weighted sequence. Axial and two coronal reformat of the T1-weighted sequence show the color-coded hearing-related brain structures we studied: Heschl’s gyrus (HG, purple, anterior HG (aHG, blue), planum temporale (PT, dark green), medial geniculate nucleus (MGN, light green), and nucleus accumbens (NA, orange).