A Clinical Analysis of Hearing Acuity in Newborn Infants

Early detection of deafness is of paramount important for the success of rehabilitation of the deaf child. In asmuch as complete deafness in usually not detected until the second year of life, it seems to be reasonable that the test for hearing should be made as a part of the physical examination in the newborn nursery. It is possible that such routine test in nursery could give an accurate statistical data regarding to the incidence of true congenital deafness at an early age. The purpose of this investigation is to detect the deafness as early as possible in order to treat properly. This paper represents the findings of a study investigated auditory responses of 100 neonates by Beltone Audiometer Model 15 CX, who are delivered normally at Ewha Womans University Hospital. The results are as follows: 1. The response according to the sound stimulation was 79 cases among 100 cases(79%). 2. The degree of intensity in response revealed strong response(41%), weak but clear response(29%), obscured response(13%), paroxysmal response(9%), and non-response(8%). 3. The relation between infant state and response rate revealed 90.0% neonates in light sleep, 78.7% in awake and 46.2% in deep sleep. 4. Response rate according to the age showed 71.4% of 1 day, 86.1% of 2 days, 83.3% of 3 days, 80.0% of 4 days and 100.0% of 5 days. 5. Simple response was 69.6% and combined response was 30.4% and auditory response of neonates was in 20 cases of cochleopalpebral reflex(18.3%), 19 cases of open eyelid or eyeball shift(17.3%), 13 cases of grimace(11.9%), 9 cases of Moro reflex(8.3%), 8 cases of movement(74%), 8 cases of sucking(7.4%), 7 cases of ceasing activity(6.4%) and 7 cases of deep respiration(6.4%). 6. Response rate was 79% when 3000Hz, 90dB was applied but it was 67% in 500Hz, 90dB. 7. When recheck was done 3 weeks later in obscured and non-response group, all showed positive auditory responses. In conclusion, the auditory response in neonatal period is greatly important, not only its incidence but early detection for the proper treatment. Therefore auther recommend the mass screening of hearing acuity among newborn infants in all nurseries as part of the routine neonatal evaluation.