Recurrence rate and corneal astigmatism after ‘sliding flap’ technique with intraoperative application of 0.05% mitomycin C or 20% ethanol for pterygium surgery

Objectives:
The aim of the study was to evaluate changes in corneal astigmatism and recurrence rates of two variants of ‘sliding flap’ techniques – with intraoperative use of 0.05% mitomycin C or 20% ethyl alcohol which could be an option for other pterygium surgeries.

Material and methods
Fifty eyes from 45 patients with primary pterygia were included. All patients underwent the ‘sliding flap’ surgery performed by a single surgeon with adjunctive intraoperative 0.05% mitomycin C (group MMC–27 eyes) or 20% ethyl alcohol (group ALC–23 eyes) therapy. Follow-up visits were at months 1, 3, 6 and 12. Patients were examined in the slit lamp for pterygium recurrence defined as any fibrovascular growth of conjunctival tissue extending across the limbus. Moreover, before and 12 months after surgery keratometry was performed in order to estimate corneal astigmatism (only in eyes without pterygium recurrence).

Results
During 12 moths of follow-up, only two recurrences (7.4%) were observed in the MMC group and 3 (13.0%) in the ALC group. In both groups, there was a visible but statistically insignificant reduction in corneal astigmatism compared to the preoperative measurement (before the surgery > MMC group: 1.2 ± 0.8 Dcyl, ALC group 1.3 ± 1.3 Dycl, 12 months postoperatively > MMC group: 0.9 ± 0.7 Dcyl, 0.8 ± 0.6 Dcyl, respectively).

Conclusions
The ‘sliding flap’ techniques combined with intraoperative 0.05% MMC or 20% ethanol application are equally effective surgical alternatives for preventing recurrence of primary pterygium. The procedures are simple with a satisfactory cosmetic effect and lack of major complications.