Spectrum of middle and inner ear abnormalities in infants with congenital heart defect

Abstract

Objectives: Congenital heart defects (CHD) occur in thousands of newborns and approximately 1,000,000 Americans with CHD are alive. A high incidence of hearing loss was documented in children with CHD; however, the histopathologic basis of hearing impairment in infants with CHD has not been systematically studied. The aim of this study was to evaluate temporal bone histopathology in infants with CHD. Methods: Forty temporal bones obtained from 20 infants with CHD were evaluated. Microdissection and serial sectioning methods were used to examine temporal bones. Subjects were divided into nonsyndromic CHD and syndromic CHD groups. The presence of temporal bone abnormalities and the incidence of abnormalities that may result in hearing impairment were determined. Results: Sixteen infants had nonsyndromic CHD and 4 had syndromic CHD. All nonsyndromic CHD cases had abnormalities such as mesenchymal remnant, malformed stapes, stapedial artery remnant, facial canal dehiscence, short cochlea, missing organ of Corti, strial basophilic deposits, widened and shortened spiral ligament, bulging Reissner’s membrane, and hypoplastic lateral semicircular canal. All syndromic CHD cases had abnormalities including large pinnae, external ear canal stenosis or atresia, narrow round window niche, facial canal dehiscence, strial deposits and cysts, and outer hair cell loss. Congenital middle and inner ear abnormalities that may impair hearing were observed in 4 subjects with nonsyndromic CHD and in 1 subject with syndromic CHD. Conclusions: A wide variety of temporal bone abnormalities were documented in infants with CHD. Congenital middle and inner ear abnormalities should be anticipated in the hearing assessment of infants with CHD.