VESTIBULAR RESPONSE DURING SLEEP AND ITS APPLICATION TO THE VESTIBULAR TEST FOR YOUNG CHILDREN

Abstract

For the purpose of developing a new vestibular test for young children, a basic study of caloric eye deviation during sleep was performed in normal adults, infants and young children.The same test was applied for infants and young children with hearing impairment.The following results were obtained;1) The caloric response during sleep was manifested as eye deviation to the stimulated side with water of 30-C and as deviation to the contra-lateral direction with water of 44-C.The sleep condition of the stage 3 of Dement-Kleitman was estimated to be most suitable for the caloric test during sleep.2) The means with standard deviations of the duration of eye deviation during sleep were 108. 5-18.7 sec with water of 30-C and 99. 6-12. 7 sec with water of 44-C in normal adult subjects; 70.5-26.4 sec with 30-C and 77.0-33, 4 sec with 44-C in infants of 4 to 18 months; 77. 1 -h 18. 8 see with 30-C and 70.6-32.8 sec with 44-C in children of 19 months to 3 year; 76. 6-20.6 sec with 30-C and 74.2-24.8 sec with 44-C in 4 to 7 year old children.3) There was a positive correlation between the duration of eye deviation following caloric stimulation during sleep and that in wakeful state in the adult group (r=0.74 in the test using water of 30-C and 0.67 in the test using water of 44-C).4) The rate of success of the test in infants and young children was in the range from 62. 5 % to 91.0%. The latency of the caloric response during sleep was longer and the duration of the response was shorter in children than in adults.5) For those children with hearing impairment, all the subjects except one proved the test results to be within the normal range