Effects of wound architecture and suture technique on postoperative astigmatism

BACKGROUND AND OBJECTIVE: A prospective randomized investigation was performed to evaluate the effects of wound architecture and suture techniques on postoperative astigmatism after phacoemulsification and intraocular lens implantation. PATIENTS AND METHODS: Two hundred eyes with preexisting with- the-rule astigmatism were randomized into four groups: (1) sutureless scleral tunnel frown incision, (2) scleral tunnel frown incision with a horizontal suture, (3) scleral tunnel frown incision with both a horizontal and a running suture, and (4) posterior limbal acute beveled cataract incision with a running suture. All the incisions were placed in the vertical steep meridian. RESULTS: Data were analyzed from 128 cases with 1-year follow-up. The results revealed that at the 2-month postoperative visit, preexisting astigmatism was significantly reduced in group 1 (P = .029) and significantly increased in groups 3 (P = .020) and 4 (P = .005). There was no significant change in group 2 (P = .06). By the 1-year postoperative visit, there was no significant difference in astigmatism from preoperative levels for all four groups. Vector analysis revealed no significant difference in the mean surgically induced cylinder at 1 year in all four groups. The number of eyes with induced against-the-rule astigmatism, however, was significantly higher than the number of eyes with induced with-the-rule astigmatism in all four groups (P < .01). CONCLUSION: The authors found that sutured wounds placed in the vertical steep meridian may initially increase with-the-rule astigmatism, whereas non-sutured wounds placed in the vertical steep meridian may initially reduce with-the-rule astigmatism. By 1 year, however, a mean flattening of the vertical steep meridian was observed in the three groups with sutures as well as in the group without sutures.