Alteration of Vestibular Function in Pediatric Cochlear Implant Recipients

Abstract

Background: Vestibular dysfunction is a complication of cochlear implantation (CI). Reports on the evaluation of vestibular function before and after CI are limited, especially in children. We investigated the effect of CI on vestibular function in pediatric patients.Patients and Methods: We routinely evaluated vestibular function before but not immediately after CI. Therefore, patients who underwent sequential bilateral CI were enrolled in this study. Seventy-three children who underwent sequential CI from 2003 to 2020 at our hospital were included. Since the vestibular function of the first implanted ear was evaluated before the second surgery for the contralateral ear, post-CI evaluation timing differed among the cases. The evaluation included a caloric test, a cervical vestibular-evoked myogenic potential (cVEMP) test, and a damped rotation test. The objective variables included the results of these tests, and the explanatory variables included the age at surgery, cause of hearing loss, electrode type, and surgical approach used. The associations of these tests were analyzed.Results: cVEMP was the most affected after CI (36.1%), followed by the caloric test (23.6%), and damped rotation test (7.8%). Cochleostomy was significantly more harmful than a round window (RW) approach or an extended RW approach based on the results of the caloric test (p = 0.035) and damped rotation test (p = 0.029). Perimodiolar electrodes affected the caloric test results greater than straight electrodes (p = 0.041). There were no significant associations among these tests' results.Conclusions: Minimally invasive surgery in children using a round window approach or an extended round window approach with straight electrodes is desirable to preserve vestibular function after CI.

Outcome of canalith repositioning manoeuvre in benign paroxysmal positional vertigo in children and adolescents: A systematic review

“…A combined multi‐disciplinary clinic such as a post‐concussion clinic may contribute to a higher number of BPPV cases in children 14 . Although not found in any patients in this review, BPPV secondary to cochlear implant was reported by several authors, 6,26,27 which is postulated to occur due to (1) introduction of the bone dust into the labyrinth, 26 (2) otoconia that dislodged from the vibration caused by the drilling during the surgery or trauma, 6 (3) labyrinthitis 28 or (4) hydropic changes from the electrode placement in the cochlea which disturbs the endolymph flow 29 …”

Vestibular dysfunction in pediatric patients with cochlear implantation: A systematic review and meta-analysis

“…After reviewing the research references, five additional studies were identified. Thus, 20 studies were finally selected for the meta-analysis ( 7 , 15 , 26 – 43 ) ( Figure 1 ).…”

“…In our study, we calculated the RR to directly compare the differences in vestibular function damage between the two surgical methods. Compared with cochleostomy, Koyama et al ( 7 ) and Cozma et al ( 33 ) reported that the risk of vestibular loss was reduced by 47 and 16%, respectively, when performing RW. Nevertheless, no significant difference was observed.…”

“…Although CIM is a safe and conventional surgical procedure, the possible consequences and risks posed by CIM should be evaluated (3). As the importance of vestibular preservation has been widely acknowledged, an increasing number of studies have found that CIM can increase the risk of vestibular dysfunction (4)(5)(6)(7)(8)(9)(10)(11)(12). Congenital or acquired vestibular dysfunction in infants and children normally leads to impaired postural control, gait disturbances, and delayed locomotion development (13)(14)(15).…”

Cochlear Implantation in Children with Enlarged Vestibular Aqueduct: A Systematic Review of Surgical Implications and Outcomes

“…Vestibular function in children is sparsely reported. Koyama et al (2021) showed that minimally invasive surgery in children using the RW approach or an extended RW approach with straight electrodes is desirable to preserve vestibular function after CI. West et al (2021) describe that the vestibular function in individuals with Pendred appears to be normal (as estimated by video head impulse test), but the saccular function is abnormally sensitive, as documented by low cervical vestibular evoked myogenic potential thresholds and high amplitudes, which agrees with a "third window" effect secondary to the large vestibular aqueduct.…”