Introduction Similarities between the peripheral auditory and vestibular systems suggest that children with sensorineural hearing loss (SNHL) may demonstrate associated vestibular impairments. The current study examines vestibular function in a previously reported cohort (n = 40) augmented by 113 children with profound SNHL. Methods The current study is prospective and cross-sectional with repeated measures. Horizontal canal function was assessed in response to caloric and rotational stimuli. Saccular function was examined using vestibular evoked myogenic potentials (VEMP). One hundred fifty-three children were tested; 119 had unilateral cochlear implants (CIs) at time of testing, and 34 were evaluated before CI. Results Horizontal semicircular canal function was abnormal in response to caloric stimuli in 50% (69/139), with a proportion (18/69, 26%) reflecting mild to moderate unilateral abnormalities. Severe hypofunction or areflexia occurred in 37% (51/139). Horizontal semicircular canal function in response to rotation was abnormal in 47% (64/139). Bilateral reduction in VOR gain was seen across frequencies in 29% (40/139) and 13% (18/139) demonstrated isolated high-frequency (≥2 Hz) loss. Saccular function was absent bilaterally in 21% (32/135) and unilaterally in 30% (40/135). All children with meningitis (n = 11) and 46% with radiologic cochleovestibular anomalies (n = 31) had horizontal canal dysfunction, whereas 45% and 46%, respectively, displayed saccular dysfunction. Unilateral dysfunction of the horizontal canal or the saccule was equally distributed between the implanted and nonimplanted ear (14:9 and 22:18, respectively), and the differences in proportions were not statistically significant. Conclusion Vestibular end organ dysfunction occurred in half of all children with profound SNHL. Approximately one-third of the subjects displayed severe abnormalities(bilateral and/or severe loss). The likelihood of vestibular end-organ dysfunction is highly dependent on etiology, with meningitis and cochleovestibular anomalies having the highest rates of severe dysfunction.

Research from JAMA Otolaryngology–Head & Neck Surgery — A Test of Static and Dynamic Balance Function in Children With Cochlear Implants — The Vestibular Olympics

Objective: To investigate and compare the usefulness of preoperative magnetic resonance (MR) imaging and high-resolution temporal bone computed tomography (HRCT) in pediatric cochlear implant candidates. Study Design: Prospective. Setting: Tertiary referral center. Patients: A cohort of 92 pediatric patients with profound hearing. Inclusion criteria were MR, computed tomography, and cochlear implantation. Intervention. Diagnostic: All patients had preoperative imaging of the petrous temporal bone (HRCT, T2-weighted fast spin echo, axial 3D Fast Imaging Employing Steady-state Acquisition [FIESTA] MR) and brain (Fast Fluid-attenuated Inversion-recovery [FLAIR] MR). Main Outcome Measure(s): Overall prevalence of inner ear dysplasias in this population and comparison of detection rates between HRCT, T2 Fast Spin Echo (FSE), and FIESTA MR sequences. Results: Radiological abnormalities were observed in 32 and 59% of MR and HRCT temporal bone, respectively. Synchronous intracranial findings were noted in 40% on brain MR. Common vestibulocochlear nerve was observed in 3% ears and directed side of implantation. Consistent discrepancies noted on HRCT were inability to diagnose early obliterative labyrinthitis and presence of the cochlear nerve in the internal auditory canal. With respect to MR, enlarged vestibular aqueducts and narrow cochlear nerve canals were consistently under identified. Conclusion: Dual-modality imaging with HRCT and MR of petrous bone and MR brain in the precochlear implant pediatric population detects abnormalities related to deafness, which would not otherwise be found using either modality alone. There is overlap between the imaging modalities in the type of abnormalities detected, and we present a case for selective use of HRCT within a diagnostic algorithm, using the patient risk factors we have identified.