Effect of topical 5-fluorouracil on closure time of myringotomies created by a radiofrequency surgical unit in guinea pigs.
OBJECTIVE
To delay the closure time of myringotomy without inserting a ventilation tube by creating a myringotomies in guinea pigs by a radiofrequency surgical unit and using topical 5-fluorouracil (5-FU).


BACKGROUND
Topical 5-FU was used successfully in glaucoma surgery to depress the proliferation of fibroblasts, but the effects of 5-FU in the myringotomy site in delaying closure are not known. The availability of the use of a radiofrequency surgical unit in performing myringotomy and the effects of a radiofrequency surgical unit myringotomy in the patency period of the myringotomy opening are not known.


METHODS
A myringotomy in the tympanic membranes of 30 guinea pigs was created by using a radiofrequency surgical unit. Right ears of these guinea pigs were identified as the study group and sponges with 50 mg/ml 5-FU were applied topically. Saline-soaked sponges were applied to the left myringotomy site, which served as the control side for 15 minutes. Guinea pigs were separated into 2 groups. In Group 2, an additional 20 mg/ml 5-FU and saline solution were dropped into the right and left external ear on the fourth and on the 11th day, respectively.


RESULTS
In all guinea pigs, it was found that all the left-ear myringotomy sites were closed at the end of the first week. In the right ears, the myringotomy sites were closed in 75% of Group 1 and in 80% of Group 2 at the end of the second week. In the histopathologic examination of tympanic membranes, there was no apparent difference between study and control sides, but a slight increase in inflammatory findings were encountered in the study sides.


CONCLUSIONS
The closure time of the myringotomy site was delayed twice as much as in the control group in the site where topical 5-FU was applied, and the drop form of 5-FU did not create any additional delay in the closure time.
Cakir
Burak Omür
BO
Department of Otorhinolaryngology and Head and Neck Surgery and the Department of Pathology, Sişli Etfal Education and Research Hospital, Istanbul, Turkey.
Dadaş
Burhan
B
Başak
Tülay
T
Cinar
Uğur
U
Ozdoğan
Haydar Cemal
HC
Uslu
Berna
B
Turgut
Suat
S
D000818:Animals; D017115:Catheter Ablation / Q000379:methods*; D005472:Fluorouracil / Q000008:administration & dosage / Q000494:pharmacology*; D006168:Guinea Pigs; D007166:Immunosuppressive Agents / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D008876:Middle Ear Ventilation; D014432:Tympanic Membrane / Q000473:pathology; D014945:Wound Healing / Q000187:drug effects*
D007166:Immunosuppressive Agents; D005472:Fluorouracil