Evidence of Vestibular and Balance Dysfunction in Children With Profound Sensorineural Hearing Loss Using Cochlear Implants

Abstract

Similarities between the peripheral auditory and vestibular systems suggest that children with sensorineural hearing loss (SNHL) may demonstrate vestibular and balance impairments. This hypothesis was studied in 40 children with severe to profound SNHL and unilateral cochlear implants. Prospective cross-sectional study with repeated measures. Vestibular function was assessed with caloric, rotational, and vestibular evoked myogenic potential testing; balance was assessed using the balance subset of the Bruininks-Oseretsky Test of Motor Proficiency-II, a standardized test of static and dynamic balance. Horizontal semicircular canal function was abnormal in response to a caloric stimulus in 50% (16/32), with a large proportion of those [6/16 (38%)] reflecting mild to moderate unilateral abnormalities. In comparison, horizontal semicircular canal function in response to rotation was abnormal in 38% (14/37). Saccular function was absent bilaterally in 5/26 (19%) and unilaterally in 5/26 (19%) with vestibular evoked myogenic potential. Age standardized balance abilities were significantly poorer in the study population [micro = 12.9 +/- 5(SD)] compared with normal hearing controls [micro = 17 +/- 5(SD); P = .0006] and correlated best with horizontal canal function in response to a rotational stimulus (P = .004; R = 0.24). SNHL from meningitis was associated with worse balance function than other etiologies. Vestibular and balance dysfunction occurred in >1/3 of children with SNHL and cochlear implants, and is highly dependent on etiology. Although compliance with all tests was high, rotational chair testing, which assesses higher frequency motion (0.25-5 Hz) and thus more "real world" vestibular function, correlated best with dynamic balance. For this reason, rotational chair testing may represent the test of choice in this population, particularly given that it is amenable to testing children of all ages.