Purpose
to assess the occurrence of hearing loss in infants with corpus callosum agenesis comparing them to children without such malformation.
Methods
a cohort study in two parts: a retrospective from 2008 to 2011, and prospective from 2011 to 2012. The study group consisted of 12 infants diagnosed with agenesis of the corpus callosum and the control group of 12 infants, matched for sex and post conceptional age. All patients underwent otoacoustic emissions transient stimulus, Auditory Evoked Potential (analysis of the average latencies of waves I, III and V and interpeak I-III, III-V and IV 80dBnNA) and behavioral auditory tests.
Results
the analysis of the occurrence of hearing impairment evaluationotoacoustic emissions transient stimulusand Auditory Evoked Potential showed differences in both groups, withhighest percentage of normal results in the control group. There was significant difference between the ears, the latencies of wave III and I-III interpeak interval, and lower right in the control group. In behavioral assessment, there was significant difference between the groups in relation to normal and abnormal results, with higher prevalence of central alteration in the study group. Also in this group, the second assessment showed a statistically significant higher rate of abnormal results when compared to the first assessment.
Conclusion
hearing disorders in infants with corpus callosum agenesis were not identified at birth, but within the first six months of life. Most of the changes occurred in the central auditory pathway in the brainstem.
Corpus Callosum; Hearing; Evoked Potentials; Auditory; Infant
