Ginkgo biloba, a free oxygen radical scavenger, affects inflammatory mediators to diminish the occurrence of experimental myringosclerosis

The impact of topical and systemic enoxaparin sodium use on traumatic tympanic membrane perforation and myringosclerosis

The objective of this study is to investigate the effect of topical and systemic enoxaparin sodium on the healing pattern of experimentally induced tympanic membrane perforation and formation of myringosclerosis. A total of 24 Wistar-Albino strain rats were included in the study. Standard myringotomies were performed on each rat. In the first group, isotonic serum physiologic was dropped on external ear canal (control group). Topical enoxaparin was dropped on external ear canal and daily topical doses of enoxaparin were dropped on external ear canal of the rats for 14 days (topical treatment group). Third group received subcutaneous injections of enoxaparin for 14 days (systemic treatment group). Five micrometer thick sections of the bullae of the rats were stained with H&E. Inflammation, edema and sclerotic lesions and neovascularization observed in the lamina propria layer of the tympanic membrane, and total thickness of the tympanic membrane were evaluated. In intergroup comparisons, significant difference in the distribution pattern of severity of inflammation in all three groups was not observed (p = 0.784, p > 0.05). Total TM thickness differed among all three groups (p = 0.028, p < 0.05). A statistically significant difference was observed between the systemic enoxaparin and the control groups (p = 0.022, p < 0.05). A statistically significant difference was observed between the topical enoxaparin and the control groups (p = 0.037, p < 0.05). However, comparison between the topical and systemic treatment groups could not reveal any statistically significant intergroup difference (p = 0.682, p > 0.05). A significant difference was not observed among three groups as for the distribution of myringosclerotic plaques, severity of edema and neovascularization in the lamina propria (p = 0.539, p > 0.05), (p = 0.063, p > 0.05), (p = 0.152, p > 0.05). Topical and systemic enoxaparin treatment did not prevent formation of sclerotic plaques; however, it decreased TM thickness significantly in comparison with the control group.

The effect of lycopene on experimental myringosclerosis

OBJECTIVES

The aim of this study was to investigate the effect of lycopene on myringosclerosis development using histopathological and immunohistochemical analyses.

METHODS

Fifty-six intact tympanic membranes of 28 guinea pigs were included in the study. Subjects were randomly divided into four groups (n=7/group). Group I (control group) did not receive any treatment after myringotomy. Group II (lycopene treatment after myringotomy) received oral lycopene (once daily at the same time, 10mg/kg, dissolved in water, administered with a catheter). The treatment lasted seven days. Group III (lycopene treatment before and after myringotomy), received lycopene treatment (same dose and route of administration) for seven days. Myringotomy was performed on day 8, and lycopene treatment was initiated immediately, and continued for seven days (same dose and route of administration). Group IV (lycopene treatment before myringotomy) received lycopene treatment one week before myringotomy using the same method and dose for seven days. Myringotomy was performed on day 8. Lycopene was not administered after myringotomy. Fourteen days after myringotomy, myringosclerosis was evaluated automicroscopically and scored. Following decapitation, bulla were removed and immersed in a 10% formaldehyde solution. Sections were cut for histopathological and immunohistochemical examination, and thickness, sclerosis, inflammation, and collagen-IV accumulation were scored semi-quantitatively.

RESULTS

In the present study, the level of myringosclerosis was significantly lower in lycopene-treated groups compared to the control group (p<0.05). In addition, thickness, inflammation, sclerosis, and collagen-IV accumulation were significantly lower in the lycopene-treated groups compared to the control group (p<0.05). The timing of lycopene administration - i.e. before and/or after surgery - did not cause any difference with respect to myringosclerosis development.

CONCLUSION

Lycopene, a strong antioxidant, may represent a good alternative treatment to prevent the development of myringosclerosis.

Does systemic clarithromycin therapy have an inhibitory effect on tympanosclerosis? An experimental animal study

Objective:

To demonstrate the inhibitory effects of clarithromycin on in vitro tympanosclerosis.

Method:

Twenty-eight rats were divided into three groups: a clarithromycin group, a non-clarithromycin group and a negative control group. Those in the first two groups were injected with Streptococcus pneumoniae following a myringotomy, and tympanosclerosis was experimentally induced. Oral clarithromycin therapy was administered in the clarithromycin group. The other groups received no medical treatment.

Results:

All eardrums in the clarithromycin and non-clarithromycin groups developed myringosclerosis, but there was only one eardrum, in the clarithromycin group, with very severe myringosclerosis. In the clarithromycin group, 11 ears showed no inflammation and there were no ears with severe inflammation. In the non-clarithromycin group, there were 11 ears with severe inflammation. The mean eardrum thickness in the clarithromycin group was 20.93 µm and in the non-clarithromycin group it was 42.71 µm.

Conclusion:

Acute otitis media and myringotomies induced tympanosclerosis, but clarithromycin reduced the severity of tympanosclerosis.