Otopathologic Abnormalities in CHARGE Syndrome

Abstract

Objective: To perform an otopathologic analysis of temporal bones (TBs) with CHARGE syndrome.

Study design: Otopathologic study of human TB specimens.

Setting: Otopathology laboratories.

Methods: From the otopathology laboratories at the University of Minnesota and Massachusetts Eye and Ear Infirmary, we selected TBs from donors with CHARGE syndrome. These TBs were serially sectioned at a thickness of 20 µm, and every 10th section was stained with hematoxylin and eosin. We performed otopathologic analyses of the external ear, middle ear (middle ear cleft, mucosal lining, ossicles, mastoid, and facial nerve), and inner ear (cochlea, vestibule, internal auditory canal, and cochlear and vestibular nerves). The gathered data were statistically analyzed.

Results: Our study included 12 TBs from 6 donors. We found a high prevalence of abnormalities affecting the ears. The most frequent findings were stapes malformation (100%), aberrant course of the facial nerve (100%) with narrow facial recess (50%), sclerotic and hypodeveloped mastoids (50%), cochlear (100%) and vestibular (83.3%) hypoplasia with aplasia of the semicircular canals, hypoplasia and aplasia of the cochlear (66.6%) and vestibular (91.6%) nerves, and narrowing of the bony canal of the cochlear nerve (66.6%). The number of spiral ganglion and Scarpa's ganglion neurons were decreased in all specimens (versus normative data).

Conclusions: In our study, CHARGE syndrome was associated with multiple TB abnormalities that may severely affect audiovestibular function and rehabilitation.

Keywords: CHARGE syndrome; cochlear implantation; congenital abnormalities; deafness; hearing loss; inner ear; middle ear; otopathology; temporal bone pathology; vestibular diseases.