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Published on: February 27, 2018
Treatment with dexamethasone arrests the development of myringosclerosis after myringotomy
C Mattsson1, P Stierna, S Hellström
1Department of Otorhinolaryngology, Umeå University Hospital, Sweden.
Hypothesis:
To attempt to inhibit the development of myringosclerosis by intraperitoneal injection of dexamethasone.
Background:
The authors' earlier report showed that the development of myringosclerosis after myringotomy was associated with an inflammatory reaction. The present study was performed to secure evidence for this hypothesis.
Methods:
Three groups of bilaterally myringotomized rats were treated at 12-hour intervals with intraperitoneal injection of dexamethasone, RU486 (a glucocorticoid receptor antagonist), and saline, respectively. At 6, 12, 24, and 48 hours after the myringotomy, 2 animals were anesthetized on each occasion and examined otomicroscopically. The animals were then killed, and the tympanic membranes were excised and prepared for light microscopic studies.
Results:
Dexamethasone treatment retarded and diminished the development of sclerotic lesions markedly. Moreover, no inflammatory signs were seen in the flaccida specimens. When the RU486-treated animals were compared with the animals in the control group, there were no evident differences concerning the development of myringosclerosis or the extent of the inflammatory reaction.
Conclusion:
These findings confirm the earlier hypothesis that an inflammatory reaction in collagen tissue is involved in the mechanism that causes the development of myringosclerosis.
