Acta Oto-Laryngologica. 2015; Early Online, 1–5 ORIGINAL ARTICLE Hearing preservation using topical dexamethasone alone and associated with hyaluronic acid in cochlear implantation BERNARDO FARIA RAMOS, ROBINSON KOJI TSUJI, RICARDO FERREIRA BENTO, MARIA VALERIA SCHMIDT GOFFI-GOMEZ, HENRIQUE FARIA RAMOS, PAOLA ANGELICA SAMUEL & RUBENS BRITO Department of Otolaryngology, University of São Paulo School of Medicine, São Paulo, Brazil Abstract Conclusion: Topical dexamethasone associated with hyaluronic acid in cochlear implant surgery demonstrated a statistically significant difference in the preservation of low-frequency thresholds when compared with topical dexamethasone alone and a control group. Topical dexamethasone alone was not superior in hearing preservation when compared to the control group. Objective: To compare the effects of topical dexamethasone alone and associated with hyaluronic acid intraoperatively in hearing preservation in cochlear implantation. Methods: Eighteen severely to profoundly hearing-impaired adult patients with measurable hearing were divided into three groups preoperatively: cochlear implantation as a control group (group 1), cochlear implantation using topical dexamethasone intraoperatively (group 2), and cochlear implantation using topical dexamethasone associated with hyaluronic acid intraoperatively (group 3). Preimplant and postimplant low-frequency pure-tone averages (PTAs) were calculated from unaided audiograms at 125, 250, and 500 Hz. Results: The mean changes in the low-frequency PTA comparing postoperative against preoperative thresholds were 28.03 ± 6.77 dB in group 1, 30 ± 14.53 dB in group 2, and 7.23 ± 6.12 dB in group 3. There was statistical difference when comparing group 3 with groups 1 and 2 using one-way ANOVA (p = 0.002) followed by Scheffé post hoc test. Keywords: Hearing loss, cochlear implant, pharmacotherapy Introduction Hearing preservation was not an issue with the early cochlear implant models, as the available electrode designs resulted in extensive intracochlear injury, causing an irreversible loss of residual acoustic hear- ing [1]. In-depth knowledge of the anatomy and function of the inner ear as well as the inflammatory repercussions caused by the insertion trauma led to the development of soft surgery principles, new electrode designs, and pharmacotherapy. Glucocorticosteroids are used in various applica- tion forms to reduce the acute insertion trauma as well as the foreign body reaction of the implanted electrode [2]. A previous study has shown that topical use of steroids provides higher drug concentration in the perilymph with minimal side effects [3]. In recent years, hyaluronic acid has been used in cochlear implantation as a lubricant to facilitate nontraumatic electrode insertion [4] and as an inner ear sealant, avoiding perilymph contamination [5,6]. Previous studies evaluating hearing preservation with different types of electrodes associated or not with pharmacotherapy have focused on the incidence of postoperative preserved thresholds. Most of them are retrospective studies with no control group. There- fore, the role of topical dexamethasone and hyaluronic acid for hearing preservation in cochlear implantation remains unclear. The purpose of this study was to compare the effects of topical dexamethasone alone and associated with hyaluronic acid intraoperatively in hearing preservation in cochlear implantation. Correspondence: Bernardo Faria Ramos, MD PhD, Department of Otolaryngology, University of São Paulo School of Medicine, Av. Dr. Enéas Carvalho de Aguiar 255, 6th floor, Room 6167, São Paulo 05403-000, SP, Brazil. E-mail: bernardofr@hotmail.com (Received 4 October 2014; accepted 1 December 2014) ISSN 0001-6489 print/ISSN 1651-2251 online Ó 2015 Informa Healthcare DOI: 10.3109/00016489.2014.995831 Acta Otolaryngol Downloaded from informahealthcare.com by Faculdade De Ciencias Farmaceuticas De Ribreirao Preto on 03/30/15 For personal use only.