AIM: To evaluate the efficacy of riboflavin administration and ultraviolet A(UVA)cross-linking on advanced symptomatic bullous keratopathy.

METHODS: Fifteen patients with symptomatic pseudophakic bullous keratopathy(PBK)were included. Slit-lamp examination, visual acuity, foreign body sensation(FBS)questionnaire, corneal clarity grading, ocular pain intensity scale and corneal thickness measures with Pentacam and ultrasound pachymetry(UP), were performed before corneal cross-linking and 1 and 6mo thereafter. After using sodium chloride solution, for one week, the central 8mm(diameter)of the corneal epithelium was removed, and cross-linking, with riboflavin instillation every 3min for 30min, and UVA irradiation for 30min was performed.

RESULTS: Five males and 10 females with mean age of 66±13y were included. Mean follow up time was 6.2mo. Corneal transparency in all eyes was statistically significantly better 1 month after treatment than preoperatively(P<0.05). At 6mo, however, corneal transparency was better in 8 eyes, the same in 5 eyes, and worse in 2 eyes compared with preoperative levels(P= 0.218). Foreign body sensation subsided in 70% of patients. The average CCT decreased within 1mo after the procedure(P<0.05). At 6mo, all but 3 eyes had progressive swelling, and the CCT increased; however, the CCT was still statistically significantly thinner than preoperatively(P=0.006). The improvement in mean CDVA from preoperatively to 1mo postoperatively was statistically significant(P=0.010). At 6mo, no significant differences were observed(P=0.130). The pain scores at 1mo were statistically significantly better than preoperatively(P=0.007). At 6mo, however the mean pain score was higher than at 1mo and not statistically significantly different from the preoperative score(P=0.070).

CONCLUSION: Corneal CXL significantly improved corneal transparency, corneal thickness, and ocular pain 1 month postoperatively. However, it did not seem to have a long-lasting effect in decreasing pain and maintaining corneal transparency in patients with PBK. This procedure extends the time interval for corneal transplantation and increases visualization at DSAEK procedure.