Influence of conjunctival suture removal on the outcome of trabeculectomy

To evaluate the influence of early conjunctival suture removal following trabeculectomy on postoperative outcome.

In a prospective randomized clinical trial 73 eyes of 69 consecutive patients eligible for primary trabeculectomy were included in the study. Eyes were randomly assigned to a control or intervention group. Trabeculectomy was performed with a fornix-based conjunctival flap and a conjunctival running mattress-suture. In the intervention group, the conjunctival suture was removed 4 weeks postoperatively, in the control group the suture remained in place. Both groups were followed for up to 12 months and best corrected visual acuity (BCVA), refraction, corneal topography, intraocular pressure (IOP), anterior segment and fundus were assessed preoperatively and within a week, 1, 3, 6 and 12 months after surgery. Statistical analysis was performed using SPSS for Windows (t test for independent samples).

Trabeculectomy induced similar astigmatism in both groups. Compared to the control group, suture removal seemed to improve BCVA at 6 and 12 months. This was associated with a significantly lower IOP at 6 and 12 months and a significantly higher complete success rate at 12 months (94 vs. 65%, p < 0.001). Astigmatism was not significantly altered by suture removal.

Conjunctival suture material appears to hamper trabeculectomy success and postoperative visual acuity. This is independent of postoperative astigmatism. Early removal of conjunctival sutures is advisable.