Normalization of Bone Conduction Auditory Brainstem Evoked Responses in Normal Hearing Individuals.

OBJECTIVES: Auditory brainstem responses (ABR) are used to evaluate the peripheral and central functions of the auditory tract. Air and bone-conduction auditory stimuli are used to evaluate the type and degree of hearing loss. The wave latencies and interpeak latencies (IPLs) are the important diagnostic data in ABR tests. Gender and age of the patients are some of the factors affecting these latencies. This study investigated the effects of age and gender on the wave and IPLs of bone-conduction ABR. MATERIALS AND METHODS: One hundred healthy individuals (50 women and 50 men) aged between 10 and 60 years were enrolled into this study, and both ears of all subjects (200 ears total) were included in the assessments. Based on their age, the subjects were equally divided into five groups, and each group consisted of 10 men and 10 women. RESULTS: The findings showed a significant difference in wave latencies and IPLs between the two genders (p<0.05). Depending on stimulus intensity, wave latencies also showed statistically significant differences between the age groups (p<0.05). However, no significant difference was noted between the age groups regarding IPLs. CONCLUSION: Normative values that covered wave latencies and IPLs evoked at stimulus intensities of 50, 30, and 10 dB nHL were established for the clinical use and use as a reference for the bone-conduction ABR testing procedure.

[Efficacy of topical ciprofloxacin and tobramycin in combination with dexamethasone in the treatment of chronic suppurative otitis media]. / Kronik süpüratif otitis media tedavisinde topikal siprofloksasin ve tobramisinin deksametazon ile kullanimi.

OBJECTIVES: To evaluate the efficacy of topical ciprofloxacin and tobramycin with and without topical dexamethasone in the treatment of chronic suppurative otitis media without cholesteatoma. PATIENTS AND METHODS: The study included 103 ears of 80 patients (49 males, 31 females; mean age 31 years; range 18 to 60 years) with chronic suppurative otitis media without cholesteatoma. The patients were randomly divided into four groups to receive topical applications of either ciprofloxacin and tobramycin alone, or in combination with dexamethasone. Cultures were obtained from the ears preoperatively and 24 hours after treatment. RESULTS: Aerobic bacteria were isolated in 94.1% of patients before the treatment, the most common being Pseudomonas aeruginosa (38.9%). With dexamethasone, the clinical response for ciprofloxacin and tobramycin increased from 80% to 90% and from 70% to 75%, respectively, but this improvement was not significant (p > 0.03). Addition of dexamethasone to ciprofloxacin decreased the recovery period from 14 days to seven days, whereas no change (7 days) was observed with tobramycin. CONCLUSION: The efficacy of ciprofloxacin and tobramycin were similar in the treatment of chronic suppurative otitis media. Addition of dexamethasone to ciprofloxacin decreased the treatment period.

The role of free oxygen radicals in noise induced hearing loss: effects of melatonin and methylprednisolone.

The aim of this study was to investigate the role of cochlear damage caused by free oxygen radicals occurring as a result of exposure to noise and to determine the prophylactic effects of melatonin and methylprednisolone. Fifty male albino guinea pigs were randomly divided into five groups. All groups were exposed to 60 h of continuous wide band noise at 100+/-2 dB, except group I. Group I was not exposed to noise or treated with drugs. Group II was exposed to noise and not treated with drugs. Group III was exposed to noise and treated with melatonin. Group IV was exposed to noise and treated with methylprednisolone. Group V was exposed to noise and treated with melatonin and methylprednisolone. A high dose of 40 mg/kg methylprednisolone and/or 20 mg/kg melatonin were administered intramuscularly 24 h before exposure to noise, immediately before noise exposure and once a day until noise exposure was completed. Just after the noise ended, guinea pigs were decapitated. Venous blood was obtained into tubes with EDTA and it was used to measure activity levels of plasma malondialdehyde, erythrocyte glutathione peroxidase and the cochlear tissue malondialdehyde. After the noise ended, in comparison group II with I; it was found that the malondialdehyde activity of the plasma and tissue had increased, the erythrocyte glutathione peroxidase activity levels had decreased and consequently, hearing thresholds had increased (P<0.01). A significant difference was found in the malondialdehyde and erythrocyte glutathione peroxidase activity levels between groups II and III (P<0.01) and the hearing thresholds exhibited a parallel trend (P<0.05). The hearing threshold and malondialdehyde activity levels obtained from groups IV and V were found to be similar to those of group II (P>0.05). As a conclusion, we suggest that the use of methlyprednisolone in order to prevent the cochlear damage caused by noise does not provide sufficient prophylaxy, however the use of melatonin provides a more effective prophylaxy, thus being a promising alternative.