AIM: To evaluate the changes in intraocular pressure(IOP)after laser suture lysis after trabeculectomy associated with 5-Fluoroaracil and the correlate the effect in relation to the time of laser suture lysis.

METHODS: Prospective interventional study of sixty eyes of sixty patients. Trabeculectomy associated with 5-Fluoroaracil was performed for 60 patients with glaucoma. Laser suture lysis was carried out according to the IOP of post trabeculectomy. 21mmHg was used as the cut off for the achievement of target IOP. According to the timing of laser suture lysis, patients post trabeculectomy were divided into three groups: <2wk, 2^nd-4^thwk and >4wk.

RESULTS: The differences of IOP prelaser suture lysis showed no statistical significance among three groups(P=0.999). The difference of IOP following 12wk post laser suture lysis showed significant statistical significance(P<0.05)among three groups. When laser suture lysis was performed during 2^nd-4^th week post trabeculectomy, 28 patients(74%)achieved the target IOP. Target IOP achieved is negatively correlated to higher week of lysis(P_trend=0.069).

CONCLUSION: Laser suture lysis during 2^nd-4^th week post trabeculectomy associated with 5-Fluoroaracil is an effective and safe technique for reducing IOP.