Effect of intraoperative 5-fluorouracil and low molecular weight heparin on the outcome of high-risk proliferative vitreoretinopathy

Purpose: To evaluate the efficacy of a combination of 5-fluorouracil (5-FU) and low molecular weight heparin (LMWH) during vitrectomy, as adjuvants in preventing proliferative vitreoretinopathy (PVR). Design: Double-blind, prospective, randomized placebo-controlled trial. Methods: Forty consecutive patients diagnosed with rhegmatogenous retinal detachment with high-risk PVR, were randomized to study and control groups (n = 20 each). Study group (group 1) patients underwent vitrectomy with the use of both intraoperative 5- FU (0.2 mg/ml) and LMWH (5 IU/ml). In the control group (group 2), a similar surgery was performed without the use of adjuvants. Patients were evaluated at 1 month, 3 months and 6 months after surgery. Postoperative retinal reattachment, recurrence of PVR, best-corrected visual acuity and complications at the end of 6 months were compared between the two groups. A Chi-square statistical analysis was used on all of the outcome measures. Results: At 6 months post-surgery, 62.5% of patients had reattached retina. There was no significant difference (Chi-square test showed x^2 = 0.106, P = 0.7447, P 0.05) in retinal reattachment in both of the groups. The rate of postoperative PVR in the control group was 55%; in the study group, the rate was 45% (the Chi-square test showed x^2 = 0.4, P = 0.5271, P 0.05), which proves statistically insignificant. In addition, there was no statistically significant difference in visual outcomes between the two groups (Chi-square test showed x^2 = 0.1002, P 0.05), no significant difference in the complication rate and drug toxicity was noted between two groups. Conclusions: This study fails to prove the efficacy of the intraoperative use of 5-FU and LMWH in combination as an antiproliferative regiment for the prevention of postoperative PVR or improvement in final visual acuity. At the same time, no significant complications could be attributed to the treatment.