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Objectives: This study investigated the effects of ascorbic acid and N-acetyl cysteine (NAC) antioxidants on the development of myringosclerosis (MS) in an experimental model., Methods: Myringotomies were performed in the ears of 15 guinea pigs, and Spongostan pieces were placed on the perforated regions of the tympanic membrane. The subjects were divided randomly into three groups and treated with three different solutions on the Spongostan-group 1: (control, 0.9% saline), group 2 (ascorbic acid), and group 3 (NAC). On day 15 after treatment, specimens from the tympanic membranes were obtained and examined via light microscopy. Sclerosis and inflammation scores and the tympanic membrane thicknesses were evaluated. Immunohistochemical methods were used to evaluate the expression of VEGF, TGF-β, iNOS, and IL1-β in all groups., Results: Lower sclerosis and inflammation scores and reduced tympanic membrane thicknesses were observed in groups treated with NAC or ascorbic acid compared with the control group. Immunohistochemical studies revealed significantly less expression of VEGF, TGF-β, and iNOS in groups 2 and 3 compared with group 1. Additionally, IL1-β expression was significantly less in group 3 than in group 1. Compared with group 1, group 2 animals exhibited reduced inflammation in the lamina propria, fewer active fibroblasts, less leukocyte infiltration, and decreased thickness of the vessels; group 3 animals exhibited decreased numbers of active fibroblasts and collagen fibers in the lamina propria., Conclusions: Inflammation scores, cellular infiltration, and expression of VEGF, TGF-β, and iNOS were reduced by ascorbic acid and/or NAC treatments, thereby decreasing MS development. Decreased expression of IL1-β was observed only in animals treated with NAC., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Tympanosclerosis is a sequel of chronic otitis media characterized by the deposition of calcareous plaques following hyaline degeneration in the fibrous layer of the tympanic membrane and inside middle ear mucosa. It usually results from prior middle ear infections. In this study, results of treatment and clinical findings of the patients with tympanosclerosis are presented. Our objective is to determine the changes in middle ear caused by tympanosclerosis and intervene in the more problematic zone and find out the more useful treatment protocol for patients. Preoperative features, middle ear findings detected during surgery and postoperative hearing levels of the patients who were operated in our clinic between January 1996 and June 2006 due to tympanosclerosis were evaluated. Surgical treatment was performed on a total of 37 patients including 25 females and 12 males between ages of 11 and 71. Preoperative tympanic membranes perforations were presented at a rate of 91% and average airway bone gap was 37.8 dB. Bilateral involvement was present in 59%. Conductive-type hearing loss was present at a rate of 81%, whereas mixed-type hearing existed at a rate of 19%. Sclerotic plaques were most commonly localized in the attic with a rate of 72%. Post-op outcome was found to be 27% in the patients with air bone gap between 0-20 dB. The best hearing result belonged to type 1 patients. Cases in which stapes footplate was fixated had the worst result in terms of hearing. Teflon piston was only applied in one patient. Our tympanoplasty success was found to be 67%. The most common treatment method of tympanosclerosis is surgery. Stapedectomy is recommended in surgery instead of mobilization techniques. However, there is often recurrence and there is no curative treatment. Therefore rehabilitation with hearing device can be preferred as an adjunct. In the recent experimental studies, good results with topical or systemic agents have also been promising.

Abstract: Objective: To investigate the ototoxic effect of boric acid solution prepared with different degree of alcohol. Methods: This study was performed on 28 young albino guinea pigs. After the animals divided four groups prior to the application of the solution an auditory brainstem response (ABR) test was applied to the each animal under general anesthesia. Their tympanic membranes perforated and test solutions were administrated to the middle ear through the perforation. On 15th day, ABR measurements were carried out and comparison was made with preadministration values. Results: The degrees of hearing loss occurring as a result of the administration of 4% boric alcohol solutions prepared with 60° and 40° alcohol differed significantly (p <0.001). Conclusion: It was established that 4% boric acid solution prepared with 60 alcohol affected hearing in guinea pigs more negatively and an increase in degree of alcohol also increased the ototoxicity of the boric acid solution. [Copyright &y& Elsevier]