Introduction: 
Electrode insertion during cochlear implantation may result in cochlear injury, inflammation, and cellular apoptosis, impacting residual hearing. We have undertaken an experimental animal study on how dexamethasone-containing Pluronic-coated gold nanoparticles (Plu-AuNPs) affect the rats’ residual hearing following cochlear implantation.
Methods:
Seven rats were included in a prospective study. The Plu-AuNPs containing dexamethasone were administered in one ear. The contralateral ear served as control. The nanoparticles were inserted into the round window niche after the intracochlear dummy electrode had been inserted through the round window. We administered free dexamethasone (Dex) in the control group after the same surgical procedure. The auditory brainstem response thresholds to pure tones at 8 kHz, 16 kHz, 24 kHz, and 32 kHz were assessed prior to the surgery and one week after. The variables were tested using a two-tailed T-test. The cutoff for statistical significance was p <0.05.
Results:
The auditory threshold shift was smaller in the Plu-AuNP with dexamethasone group than it was in the free dexamethasone group, but there was no statistically significant difference between the groups. When compared separately, the 8 kHz frequency demonstrated statistically significant improvements in favor of the Plu-AuNP group one week after surgery. The Dex-Plu-AuNPs had a substantially lower mean postoperative 8 kHz threshold than the control group (p = 0.048, t-test). The statistical analysis revealed no discernible changes in the mean threshold shifts of the two cohorts for the other frequencies.
Conclusions:
Following cochlear implantation, the local administration of Plu-AuNPs with dexamethasone may provide greater protection of residual hearing than dexamethasone alone, although a larger sample size is required to detect any potential statistical significance. Plu-AuNPs with dexamethasone does not appear to present toxicity for the inner ear and could potentially act as a carrier for other therapeutical agents. Plu-AuNPs with dexamethasone have the prospects of preserving lower frequencies in individuals with partial deafness who are suitable for electric acoustic stimulation (EAS). If we consider this propensity, Plu-AuNPs with dexamethasone might be advantageous for patients with Ménière's disease.


Prospects for functionalized gold nanoparticles in minimizing local inflammation after cochlear implantation-Experimental Study

It is with great pleasure and enthusiasm, that on behalf of the Cochlear Implant centers of the Radboud UMC in Nijmegen and Erasmus MC Sophia Children’s Hospital in Rotterdam to invite you to attend the 16th European Symposium on Pediatric Cochlear Implantation to Rotterdam, the Netherlands in 2023.

Yours sincerely, on behalf of the CI Centers at Radboud UMC and Erasmus MC,