Article

Radiofrequency myringotomy with the topical use of mitomycin C: An experimental study

Department of Otolaryngology, University of Crete, School of Medicine, Heraklion, Crete, Greece.
Ontology & Neurotology (Impact Factor: 1.6). 02/2006; 27(1):4-7. DOI: 10.1097/01.mao.0000172411.80154.99
Source: PubMed

ABSTRACT To assess the use of radiofrequency myringotomy in combination with mitomycin C as an alternative myringotomy technique on rabbits.
Experimental animal research protocol.
University of Crete, School of Medicine, Medical Experimental Education and Research Center.
Radiofrequency myringotomies were performed under general anesthesia on both ears of 20 rabbits. Mitomycin C (0.3 mg/ml) pledgets were applied in the right ears (study group) and saline pledgets in the left ears (control group). Animals were monitored using otomicroscopy weekly until myringotomy closure. Kaplan-Meier survival techniques were used to compare myringotomy patency time between the two sides.
Radiofrequency myringotomy under general anesthesia on both ears of 20 rabbits.
Myringotomy patency time.
The mean patency time of the study group was 5.45 weeks (95% confidence interval, 5.185-5.715 weeks). The mean patency rate for the control side was 1.60 weeks (95% confidence interval, 1.38-1.82 weeks). The Breslow (generalized Wilcoxon) test showed the study group to have significantly longer patency of radiofrequency myringotomy than the control group (p<0.0001).
The patency period of radiofrequency myringotomy was not long enough to be proposed as an alternative to the insertion of ventilation tubes, although mitomycin C had a significant adjunct effect in prolonging the patency rate of radiofrequency myringotomy on rabbits.

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