Integrity of the Auditory Pathway in Young Children with Congenital and Postmeningitic Deafness

Abstract
This study compares the functional integrity of the auditory pathways of congenitally deaf and postmeningitically deaf children. We used the electrical auditory brain stem response evoked by promontory stimulation to assess 49 profoundly deaf children before cochlear implantation. The age at implantation ranged from 21 months to 15 years (mean 4.5 years). The onset of deafness was either congenital or up to the age of 2 years (mean 5 months). The cause of deafness was meningitis in 19 children (39%) and congenital in 30 (61%). The number of children with identifiable waveform components (eV, eIII, and eII) was significantly greater in the congenitally deaf group. We also analyzed the amplitudes, the latencies, and 4 parameters of the amplitude input-output functions. All the statistically significant differences were in favor of better responses in the congenitally deaf children. These results suggest that the functional status of the peripheral neurons of the auditory pathways may be more intact in congenitally deaf children than in postmeningitic children.