Cochlear implantation initiates an inflammatory cascade in which both acute insertion trauma and chronic foreign body reaction lead to intracochlear fibrosis and loss of residual hearing. Several strategies have been proposed to attenuate the local reactive process after implantation, including intracochlear drug delivery. The present study gives an overview of what is being investigated in the field of inner ear therapeutics and cochlear implant surgery. The aim is to evaluate its potential benefit in clinical practice. A systematic search was conducted in PubMed, Embase, and Cochrane Library databases identifying comparative prospective studies examining the effect of direct inner ear drug application on mechanical cochlear trauma. Both animal and human studies were considered and all studies were assessed for quality according to the validated risk of bias tools. Intracochlear administration of drugs is a feasible method to reduce the local inflammatory reaction following cochlear implantation. In animal studies, corticosteroid use had a significant effect on outcome measures including auditory brainstem response, impedance, and histological changes. This effect was, however, only durable with prolonged drug delivery. Significant differences in outcome were predominantly seen in studies where the cochlear damage was extensive. Six additional reports assessing non-steroidal agents were found. Overall, evidence of anti-inflammatory effects in humans is still scarce.

Purpose: Vestibular implant electrode positioning close to the afferent nerve fibers is considered to be key for effective and selective electrical stimulation. However, accurate positioning of vestibular implant electrodes inside the semicircular canal ampullae is challenging due to the inability to visualize the target during the surgical procedure. This study investigates the accuracy of a new surgical protocol with real-time fluoroscopy and intraoperative CT imaging, which facilitates electrode positioning during vestibular implant surgery. Methods: Single-center case-controlled cohort study with a historic control group at a tertiary referral center. Patients were implanted with a vestibulocochlear implant, using a combination of intraoperative fluoroscopy and cone beam CT imaging. The control group consisted of five patients who were previously implanted with the former implant prototype, without the use of intraoperative imaging. Electrode positioning was analyzed postoperatively with a high-resolution CT scan using 3D slicer software. The result was defined as accurate if the electrode position was within 1.5 mm of the center of the ampulla. Results: With the new imaging protocol, all electrodes could be positioned within a 1.5 mm range of the center of the ampulla. The accuracy was significantly higher in the study group with intraoperative imaging (21/21 electrodes) compared to the control group without intraoperative imaging (10/15 electrodes), (p = 0.008). Conclusion: The combined use of intraoperative fluoroscopy and CT imaging during vestibular implantation can improve the accuracy of electrode positioning. This might lead to better vestibular implant performance.

Vestibular hypofunction in children can lead to frequent falls and delayed motor development. Especially children with bilateral vestibular hypofunction (BVH) are most at risk for developing symptoms. These children might benefit from future therapies, like vestibular implants, to restore their vestibular system. This study aimed to describe the prevalence, etiology, motor development, and hearing status of pediatric patients with BVH. A multicenter retrospective chart review of 492 children with sensorineural hearing loss was performed. Children with at least one bilaterally abnormal vestibular test were defined as having a BVH. BVH was found in 23 % of the screened children. Especially children with syndromic hearing loss like Usher, CHARGE, or Waardenburg syndrome and infectious etiologies like congenital CMV and meningitis, were prone to have BVH on all performed tests. Children with BVH had a high percentage of motor developmental delay (81 %), especially if all tests were abnormal on both sides (97 %). It is recommended to perform vestibular screening in children with sensorineural hearing loss, as BVH is prevalent. BVH has a very high risk of causing a delay in motor development. Especially in children with BVH on all vestibular tests, motor development is impaired. Those children might benefit from vestibular implants in the future.