Browsing by Author "Yilmaz, YF"

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Division of the stapedial tendon results in noise-induced damage to the inner ear
    Ocalan, R; Akin, FC; Yilmaz, YF; Ozlugedik, S; Gurgen, SG
    Background: The effect of division of the stapedial tendon on susceptibility to noise-induced inner ear damage has not been previously studied. This study aimed to evaluate the effects of noise exposure following division of the stapedial tendon in guinea pigs. Material/Methods: Ten adult albino guinea pigs were used. The stapedial tendon of each right ear was cut. The stapedial tendon in each left ear was left intact and these ears served as a control group. DPOAEs and ABR tests were performed before and 10 days after noise exposure. The animals were exposed to a 110-dB noise stimulus for 6 h in a silent room a week after surgery. Cochleas of the animals were removed, and inner and outer hair cells were examined under a light microscope. Results: We found that noise exposure adversely affected DPOAE measurements at all frequencies except 2 KHz in experimental ears. Noise exposure also produced significantly elevated ABR thresholds in experimental ears at 2, 4, 8, and 16 KHz. On histopathological examination, we found a significantly greater prevalence of apoptotic cells in the experimental ears. Conclusions: Based on these findings, we can conclude that after division of the stapedial tendon, noise exposure may cause damage to the inner ear. This is the first study in the English literature that demonstrates the potential protective effect of the stapedial tendon against acoustic damage.
  • No Thumbnail Available
    Item
    Effects of Parenteral Papaverine and Piracetam Administration on Cochlea Following Acoustic Trauma
    Kum, NY; Yilmaz, YF; Gurgen, SG; Kum, RO; Ozcan, M; Unal, A
    Introduction: Noise exposure, the main cause of hearing loss in countries with lot of industries, may result both in temporary or permanent hearing loss. The goal of this study was to investigate the effects of parenteral papaverine and piracetam administration following an acoustic trauma on hearing function with histopathologic correlation. Materials and Methods: Eighteen Wistar albino rats exposed to noise for 8 h in a free environment were included. We divided the study population into three groups, and performed daily intraperitoneal injections of papaverine, piracetam, and saline, respectively, throughout the study. We investigated the histopathologic effects of cellular apoptosis on inner hair cells (IHCs) and outer hair cells (OHCs) and compared the distortion product otoacoustic emissions (DPOAEs) thresholds among the groups. Results and Discussion: On the 3rd and 7th days, DPOAE thresholds at 8 kHz were significantly higher both in papaverine and piracetam groups compared with the control group (P = 0.004 for 3rd day, P = 0.016 and P = 0.028 for 7th day, respectively). On the 14th day, piracetam group had significantly higher mean thresholds at 8 kHz (P = 0.029); however, papaverine group had similar mean thresholds compared to the control group (P = 0.200). On the 3rd and 7th days following acoustic trauma, both IHC and OHC loss were significantly lower in both papaverine and piracetam groups. On the 7th day, the mean amount of apoptotic IHCs and OHCs identified using Caspase-3 method were significantly lower in both groups, but the mean amount identified using terminal deoxynucleotidyl transferase dUTP nick end labeling method were similar in both groups compared to the control group. Conclusion: We demonstrated the effects of papaverine and piracetam on the recovery of cochlear damage due to acoustic trauma on experimental animals using histopathologic and electrophysiologic examinations.