Medical ozone therapy for the inner ear acoustic trauma Alper Yenigun a, *, Fadlullah Aksoy b , Remzi Dogan b , Fahrettin Yilmaz c , Bayram Veyseller b , Orhan Ozturan b , Burak Ozturk d a Karaman State Hospital, Otorhinolaryngology Clinic, Karaman, Turkey b Bezmialem Vakif University, Department of Otorhinolaryngology, Istanbul, Turkey c Medipol University, Department of Otorhinolaryngology, Istanbul, Turkey d Bezmialem Vakıf University, Medical School of Health Sciences of Audiology, Istanbul, Turkey 1. Introduction The most frequent reasons for hearing loss are age, genetic factors, medicine ototoxicity and acoustic trauma. The cellular mechanism of hearing loss due to loud noise is not clearly understood. Constant exposure to high intensity acoustic trauma results in death of the outer hair cells of the organ of Corti through apoptosis [1]. The causes of cell death due to acoustic trauma are blood flow reduction in the inner ear [2], free radicals produced due to increased metabolic activity [3,4], and cellular necrosis in the outer hair cells directly induced by mechanical trauma [5]. In loss of hearing due to acoustic trauma, the reactive oxygen radicals play the role of a primer by creating an apoptotic signal in the outer hairy cells. It has been observed that hydroxyl radicals increase up to 10 times in the cochlea of rats that are constantly exposed to acoustic trauma [3]. Other studies have also shown that the number of reactive oxygen radicals in animals exposed to acoustic trauma increase up to four times compared to animals not exposed to trauma [6,7]. Medical ozone therapy is used for the treatment of inflamma- tion, infected wounds, chronic skin disease and advanced ischemic illnesses, including burns, due to its antioxidant, antiflammatory and antimicrobial effects. Pure ozone is not used in ozone therapy owing to ozone toxicity; it is applied in the form of an ozone/ oxygen mixture [8,9]. Ozone gas (O 3 ) is produced from the sun using the effects of ultraviolet rays, or it is produced artificially using an ozone generator [10]. Medical ozone treatment is a method in which a gas combination containing ozone and oxygen is applied to body liquids and cavities. It has been observed that ozone treatment significantly decreases oxidative stress in experimental rat models [11,12]. It has been observed that oxidative stress is reduced with reinfusion of blood mixed with ozone since it increases nitric oxide (NO) levels and results in a reduction in hypoxia due to vasodilatation in ischemic areas, superoxide dismutase (SOD) activation and a reduction in glutathione levels [13,14]. During infusion of ozonized blood to the recipient, the majority of the endothelial cells are activated with lipid oxidation products (LOPs), and this results in increased NO, plasma S-nitrosothiol and S- nitrosohemoglobin production. Although the half-life of NO is less International Journal of Pediatric Otorhinolaryngology xxx (2013) xxx–xxx A R T I C L E I N F O Article history: Received 21 January 2013 Received in revised form 21 June 2013 Accepted 22 June 2013 Available online xxx Keywords: Acoustic trauma Ozone therapy Inner ear Otoacoustic emission Auditory brainstem response A B S T R A C T Objectives: The goal of the study was to look at the potential protective effect of ozone therapy by studying its antioxidant and vasodilatation effects against hearing loss caused by acoustic trauma. Methods: Thirty-two male Wistar Albino rats were divided into four groups of eight. The 1st group was exposed to acoustic trauma, the 2nd group was treated with ozone initially, and was exposed to acoustic trauma 24 h later, the 3rd group received ozone without trauma, while the 4th group was the control group. The 1st and 2nd groups were exposed to acoustic trauma with 105 dB SPL white band noise for 4 h. DPOAE and ABR tests were conducted in all groups on the 1st, 5th, and 10th days after trauma. Results: In the 1st group, the effects of acoustic trauma continued on days 1, 5 and 10. The 2nd group’s DPOAE and ABR results on days 5 and 10 showed significant improvement at all frequencies compared to deterioration on day 1, and the readings were comparable to baseline measurements. Conclusion: Acoustic trauma is a pathology that is experienced frequently and leads to many problems in terms of health and cost. Ozone was demonstrated to be a reparative substance against acoustic trauma and, in addition, it can be supplied and applied easily. ß 2013 Elsevier Ireland Ltd. All rights reserved. * Corresponding author at: Karaman State Hospital, Otorhinolaryngology Clinic, Turgut O ¨ zal Street No. 1, Karaman, Turkey. Tel.: +90 505 504 0696; fax: +90 338 226 33 09. E-mail address: alperyenigun@gmail.com (A. Yenigun). G Model PEDOT-6700; No. of Pages 6 Please cite this article in press as: A. Yenigun, et al., Medical ozone therapy for the inner ear acoustic trauma, Int. J. Pediatr. Otorhinolaryngol. (2013), http://dx.doi.org/10.1016/j.ijporl.2013.06.020 Contents lists available at SciVerse ScienceDirect International Journal of Pediatric Otorhinolaryngology jo ur n al ho m ep ag e: ww w.els evier .c om /lo cat e/ijp o r l 0165-5876/$ – see front matter ß 2013 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ijporl.2013.06.020