Development of an Individualized Round Window Niche Implant for Inner Ear Drug-Delivery

Verena Scheper; Chunjiang Wei; Ziwen Gao; Farnaz Matin-Mann; Thomas Lenarz

doi:10.1055/s-0042-1746865

Laryngo-Rhino-Otologie, Table of Contents

CC BY-NC-ND 4.0 · Laryngorhinootologie 2022; 101(S 02): S243-S244
DOI: 10.1055/s-0042-1746865

Abstracts | DGHNOKHC

Otology / Neurootology / Audiology: Inner ear

Development of an Individualized Round Window Niche Implant for Inner Ear Drug-Delivery

Authors

Verena Scheper

¹Department of Otolaryngology, Hannover Medical School, Pharmacology of the Inner Ear Hannover
Chunjiang Wei

¹Department of Otolaryngology, Hannover Medical School, Pharmacology of the Inner Ear Hannover
Ziwen Gao

¹Department of Otolaryngology, Hannover Medical School, Pharmacology of the Inner Ear Hannover
Farnaz Matin-Mann

¹Department of Otolaryngology, Hannover Medical School, Pharmacology of the Inner Ear Hannover
Thomas Lenarz

²Department of Otolaryngology, Hannover Medical School Hannover

Abstract

Full Text

Introduction The use of drugs inside the cochlea is consistently gaining importance. The local and therefore more targeted application of medication has the potential to protect the health of the cochlea and lead to improved hearing results after trauma. Individualized, drug-eluting, round window niche implants (RNIs) may be an optimal method for applying the active ingredient locally to the cochlea as non-invasively as possible. A RNI was designed and validated for biocompatibility, bioefficacy and implantability.

Methods Digital images of the round window niche were transformed into DICOM (digital imaging and communications in medicine) files and the round window area was segmented (3D Slicer<sup>TM</sup > version 4.11 (http://www.slicer.org). The segmented model was exported as STL (standard tessellation language) file and 3D printed (3D-Bioplotter<sup></sup > Manufacturers Series EnvisionTEC, GmbH, Gladbeck, Germany) using UV-silicone containing dexamethasone. Printed samples were microscopically evaluated for printing accuracy, the biocompatibility was tested via 3- (4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT)-assay and bioactivity by a TNFα reduction assay. Using guinea pigs as established animal model for inner ear pharmacotherapy the implantability was determined.

Conclusion Using additive manufacturing, we developed an individualized drug delivering RNI. It was biocompatible and bio-effective in vitro. In the respective animal model it was safely inserted into the space between the round window membrane and the middle ear ossicles as well as the facial ridge without damaging one of the structures. An in vivo study to investigate the biological effect of the RNI is ongoing.

This study is funded by the Federal Ministry of Education and Research of Germany (BMBF), ‘RESPONSE – Partnership for Innovation in Implant Technology’ in the program ‘Zwanzig20 – Partnership for Innovation’.