Hearing in children with cleft palate

Abstract

Objective: The overall aim of this thesis was to collect longitudinal information about hearing thresholds and complications due to otitis media with effusion (OME) in children with cleft palate. Since OME is highly prevalent in children with cleft palate, many authors have hypothesized that the hearing loss associated to OME contributes to the delayed development of early speech and language often seen in these children. There is a lack of knowledge whether the OME-associated hearing loss is more severe in children with cleft palate compared to children with OME but without cleft.

Methods: Audiological and otological data were reviewed retrospectively in a group of children with unilateral cleft lip and palate (UCLP) from 4-10 years of age. Results of hearing tests and the number of ventilation tube (VT) treatments were analyzed (study I). In the prospective longitudinal group comparison study audiological and otological data were collected in one group of children with cleft palate, and another group of children with OME but without cleft palate. The children were followed from the neonatal auditory brainstem response assessment (ABR) at 1-4 months of age to 36 months of age. At seven different test occasions, age-appropriate hearing tests were performed (study II).

Results: In the group of children with UCLP, the proportion of children with hearing loss in the speech frequencies decreased with age. However, when examining the higher frequencies, this improvement was not found. There were no significant cor- relations between the number of VT treatments and hearing thresholds at 7-10 years of age. Four children (12%) presented with complications; perforation of the ear drum, requiring surgery (two children) and acquired cholesteatoma (two children). In the prospective longitudinal study, the comparison of the median four frequency average at 500, 1000, 2000 and 4000 Hz (4FA), and the median thresholds at 500 and 4000 Hz, at 12 months of age, demonstrated significantly better levels in the group of children with cleft palate, which might be explained by the early VT treatment at the time of the palate repair, often at 6 months of age (p < 0.001). There were no significant group-wise differences in the median 4FA or in any discrete frequencies at 24 and 36 months of age. Both groups improved over time from the neonatal ABR-test to the test at 36 months of age, p < 0.05 in CP±L-group; p < 0.001 in group without CP±L. When analyzing the thresholds from 12 months to 36 months of age, there was a significant improvement in the group without CP±L (p < 0.001), but not in the group with CP±L. At 36 months of age the median 4FA was normal in both groups.

Conclusion: Children with cleft palate have a high prevalence of OME, with a subsequent risk for long-term hearing loss. The early VT treatment in children with cleft palate appears to be favourable for the short-term hearing; however, this should be weighed against the risk for complications. Therefore, this group of children requires close monitoring with otological examinations and audiological assessments to ensure that the common OME-associated conductive hearing impairment is managed appropriately.