[The effect of topical mitomycin-C application before or after incisional myringotomy on patency times of guinea pig tympanic membrane perforations].

OBJECTIVES

The aim of this study was to investigate the effect of topical mitomycin-C application before or after incisional myringotomy on patency times and to asess its use as an alternative to ventilation tube insertion.

MATERIALS AND METHODS

Nineteen guinea pigs were divided into two groups. In the study group (n=11), mitomycin-C was applied in a concentration of 0.4 mg/ml over the perforation for five minutes before (n=6) or after (n=5) incisional myringotomies in both ears. Control animals (n=8) received 0.1 ml 0.09% NaCl for the same duration. Evaluations were made on days 1, 3, 5, 7, 10, 14, and 21. The patency times, otorrhea, and other complications were recorded.

RESULTS

Compared to controls (7.0+/-1.5 days), the mean patency times of perforations were significantly longer in mitomycin-C treated groups before (11.6+/-5.2 days) and after (14.2+/-4.7 days) incisional myringotomies (p<0.05). Patency times did not differ significantly between the two mitomycin-C groups. None of the ears exhibited permanent perforation.

CONCLUSION

The length of patency provided by mitomycin-C is not sufficient for optimal ventilation in otitis media with effusion. However, in cases requiring shorter patency times, mitomycin-C application before or after myringotomy may be an alternative to ventilation tube insertion.