Objectives: to assess function of the vestibular system through evaluation of vestibulo-ocular, the vestibulocollic and the vestibulospinal reflexes in children with sensory neural hearing loss.
Method: 40 normal hearing children (control subjects) and 80 hearing impaired children classified as mild, moderate, severe, and profound according to their hearing threshold. Ice caloric test, vestibular evoked myogenic potential (VEMP), and sensory organization test of computerized dynamic posturography (SOT-CDP) were done to test for the 3 vestibular reflexes respectively.
Results: among the 80 hearing impaired children, 36 hearing impaired children (45% ) were normal in the 3 tests, 20 patients ( 25%) had abnormal results in one test only, 16 (20%) were abnormal in 2 tests, and only 8 patients (10%) showed abnormality in all 3 tests. 16 patients 20% were abnormal in ice caloric test, 26 patients (32.5%) had abnormal VEMP result, and 30 patients (37.5%) had abnormal result in SOT- CDP. Significant moderate correlation was present between severity of hearing impairment and vestibular dysfunction (r= 0.491 for the vestibulocular reflex pathway, r= 0.458 for the vestibulocollic pathway, and r= 0.546 for the vestibulospinal reflex pathway at P value <0.05). There was also significant moderate correlation between the 3 vestibular test results; ice caloric test versus VEMP (r= 0.320), ice caloric test versus CDP (r= 0.516), and CDP versus VEMP (r = 0.455) at P value < 0.05.
Conclusion: the 3 vestibular reflex pathways can be affected in the hearing impaired children either separately or together.