Postoperative astigmatism following phacoemulsification with sutured vs. unsutured wounds

A total of 293 cases of phacoemulsification cataract surgery with a 5.0- or 6.0-mm frown incision were analysed retrospectively to compare postoperative astigmatism between cases with sutured wounds and those with unsutured wounds. Astigmatic analysis was done with a simplified method (keratometric readings with steep meridians between 46 degrees and 134 degrees were considered "with-the-rule" [WTR], and those with steep meridians less than 46 degrees and greater than 134 degrees, "against-the-rule" [ATR]). Among patients with WTR astigmatism preoperatively, the mean keratometric cylinder in the sutureless group (n = 53) was significantly lower at 1 day and at 4 to 6 months postoperatively than before surgery (p < or = 0.001); in the suture group (n = 120) the mean cylinder was significantly higher at 1 day and significantly lower at 4 to 6 months than before surgery (p < 0.05). Among patients with ATR astigmatism preoperatively, the mean keratometric cylinder in the sutureless group (n = 22) was significantly higher at 1 day than before surgery (p < 0.01); in the suture group (n = 98) the mean cylinder was significantly lower at 1 day than before surgery (p < 0.001), and the difference at 4 to 6 months almost reached statistical significance (p = 0.052). Vector analysis showed that surgically induced cylinders in the suture and sutureless groups were similar. Our findings suggest that in the short term patients with preoperative WTR astigmatism may benefit from unsutured wounds, and those with preoperative ATR astigmatism may benefit from sutured wounds if the incision is placed in the vertical meridian.