Michael Wall

Effects of ototopic steroid and NSAIDS in clearing middle ear effusion in an animal model

OBJECTIVE: A model of otitis media with effusion (OME) has been developed in the Sprague-Dawley (SD) rat. This model was used to study the effects of an ototopic steroid and nonsteroidal anti-inflammatory drug (NSAID) on lipopolysaccharide (LPS)-induced OME. STUDY DESIGN: Twenty-six rats were randomized into 4 groups: saline solution, LPS, NSAID + LPS, and steroids + LPS. Test substance was injected into the middle ear at 0, 2, and 4 hours. The effusion was collected at 2, 4, and 6 hours. Statistical analysis of effusion volume and albumin concentration was performed. RESULTS: The LPS group demonstrated statistically significant increase in both effusion volume and albumin concentration compared with saline solution. Intergroup comparison revealed significantly less effusion volume in the steroid group and less albumin concentration in the NSAID group when compared with the LPS group. CONCLUSIONS: Transtympanic steroid reduced LPS induced middle ear effusion while NSAID reduced albumin concentration in the rat model. SIGNIFICANCE: Our results lend support to the current use of anti-inflammatory ototopicals in the treatment of inflammatory middle ear disease.

Glucocorticoids reduce nitric oxide concentration in middle ear effusion from lipopolysaccharide induced otitis media

OBJECTIVE Otitis media with effusion (OME) is a common childhood disease that is characterized by an accumulation of fluid in the middle ear. Chronic OME can also lead to sensorineural hearing loss (SNHL). Nitric oxide (NO), an inflammatory mediator (IM) of OME, is a free radical known to regulate cell proliferation, cell death, and angiogenesis. Previous studies have shown that nitric oxide may cause SNHL through outer hair cell (OHC) cytotoxicity. This experiment was designed to determine whether glucocorticoids, dexamethasone, fluticasone propionate, or rimexolone, can reduce the concentration of NO in middle ear effusion (MEE). METHODS Fifty-three chinchillas were divided into 7 groups, vehicle vs. each glucocorticoid at 0.1% and 1.0% concentrations. Due to anesthesia complications, N ranged from 6 to 9 per group. Two hundred microlitres of each test article was injected into the bullae of each animal. Two hours later, lipopolysaccharide (LPS) (0.3mg in solution) was added. Test articles were re-administered at 24 and 48h post-LPS induction. After 96h, animals were euthanized and the MEE was collected. RESULTS All three glucocorticoids numerically reduced NO concentration in the middle ear when administered at 0.1%, but only FP showed a significant reduction. At 1.0% concentrations, all 3 steroids significantly reduced NO concentration. CONCLUSION This study suggests that glucocorticoid treatment reduces NO concentration in the MEE and may protect the ear from the SNHL caused by NO.

Effect of Ciprodex vs. CiproHC on LPS-induced otitis media

OBJECTIVES: The purpose of this investigation is to use distortion product otoacoustic emission (DPOAE) testing to address the issue of possible ototoxicity from use of Cortisporin otic suspension following tympanostomy tube placement. Numerous studies indicate that DPOAE testing reveals ototoxic changes before cochlear damage is detectable by conventional audiometry. Although DPOAE testing is a powerful and proven tool for detecting ototoxicity, DPOAE results have not been applied to the debate about Cortisporin. METHODS: Clinical records were retrospectively reviewed in reverse chronological order from 2007 through 2005 to find children who underwent unilateral or bilateral placement of transtympanic ventilation tubes, were treated with Cortisporin eardrops, and were evaluated postoperatively with DPOAE testing. Thirty-six children (52 ears) were included in the study group treated with Cortisporin drops following ventilation tube placement. A control group of 36 children (52 ears) who had not received drops and had no tube placement were also evaluated with DPOAE. Distortion-Product-grams (DP-grams) were generated by simultaneously presenting two pure tones to the ear recorded from the 2, 3, 4, 5, 6, 7, 8, 9, and 10 Hz. regions. Statistical analyses to compare DPOAE data for the two groups were performed using T-tests. RESULTS: No significant differences in DPOAE amplitudes were noted between the study and control groups (P .05). CONCLUSIONS: There was no significant difference in DPOAE amplitudes in children who received Cortisporin drops postoperatively after tubes compared to a control group of similar children. Results from this study indicate that Cortisporin use for five days post tube insertion is safe.

R044: Chinchilla Round Window Membrane with Otitis and Steroids

antibodies are related to the pathogenesis and grade of Meniere’s disease. METHODS: The team created Lymphoblastoid Cell Line from lymphocyte of the patient who was diagnosed with Meniere’s disease. H2O2 was used as an oxidative stressor and ATP as an activator of molecular chaperone. Autoimmune assessment was examined by auto antibodies (anti-HSP70 antibody, ANA and RF). The expression of HSP70 and BAG1 at protein was analyzed with Western blot. RESULTS: Control cells from healthy donors were resistant to H2O2, and Meniere’s disease cells were sensitive cells to H2O2. Me1, 3, 4, 7, and 10 cells were sensitive for ATP treatment. The autoantibodies were positive in the serum of patients of ATP-resistant cells. ATP treatment induced dynamic remodeling between molecular chaperones in Me1 cells. CONCLUSION: The data suggested that redox regulation and the dynamic remodeling of molecular chaperones by ATP treatment protected cells from oxidative stress in Meniere’s disease. Additionally, results showed autoantibodies might be an indicator of the grade of Meniere’s disease. SIGNIFICANCE: This system may be able to form the basis of tailor-made therapy for Meniere’s disease.