Protecting against electrode insertion trauma using dexamethasone
| Autor: | Robert Cowan, Carrie Newbold, Scott W. Chambers, Frank Risi, Karina Needham, Christopher Miller, Dimitra Stathopoulos, Godofredo Timbol, Ya Lang Enke |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
medicine.medical_treatment
Guinea Pigs Dexamethasone 03 medical and health sciences Speech and Hearing Postoperative Complications 0302 clinical medicine Hearing Cochlear implant otorhinolaryngologic diseases Electrode array Animals Medicine Hearing Loss 030223 otorhinolaryngology Glucocorticoids Spiral ganglion Cochlea Bone growth business.industry Cochlear Implantation Cochlear Implants medicine.anatomical_structure Auditory brainstem response Otorhinolaryngology Organ of Corti Anesthesia sense organs Spiral Ganglion business 030217 neurology & neurosurgery medicine.drug |
| Zdroj: | Cochlear Implants International. 20:1-11 |
| ISSN: | 1754-7628 1467-0100 |
| DOI: | 10.1080/14670100.2018.1509531 |
| Popis: | OBJECTIVE: To compare the benefits of a dexamethasone-eluting array for hearing preservation and cochlear histopathology in low trauma (soft-surgery) and high trauma models of cochlear implant surgery. METHODS: Adult guinea pigs were implanted with an intra-cochlear array using two different surgical procedures: either a soft-surgery approach or following generation of electrode insertion trauma (high trauma). Two methods of dexamethasone delivery were evaluated: elution from an electrode array alone, and elution from a cochlear implant electrode array in combination with a pre-operative systemic injection. All electrode arrays were implanted for a period of 4 weeks. Outcome measures at 4 weeks post-implantation included auditory brainstem response (ABR) thresholds, histological analysis of spiral ganglion neuron density, fibrotic tissue, new bone growth, and cochlear damage. RESULTS: Animals exposed to high surgical trauma showed greater hearing loss than those in the low trauma model, irrespective of the presence of dexamethasone. Whilst the area of intra-cochlear fibrotic tissue growth post-implantation was also independent of dexamethasone administration, new bone growth was significantly reduced in its presence. Our high trauma model effectively obliterated the organ of Corti and significantly reduced spiral ganglion neuron densities in the lower basal turn. This trauma-induced reduction in spiral ganglion neuron survival decreased with the inclusion of a dexamethasone-eluting array. A pre-operative systemic injection of dexamethasone did not significantly improve any outcome measures beyond those provided with a dexamethasone-eluting array alone. CONCLUSION: Dexamethasone-eluting intra-cochlear arrays may inhibit osteoneogenesis, and reduce spiral ganglion neuron loss following traumatic cochlear implantation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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