Comparison of Surgically Induced Astigmatism between a No-Stitch Frown Incision and a No-Stitch Straight Incision

ABSTRACT

PURPOSE: This investigation was performed to evaluate the surgically induced astigmatism of no-stitch frown incision with 4.0 mm chord length, which was compared with no-stitch 3.2 mm straight incision. METHODS: Sixty eyes, which could be observed for 3 months, were divided into two groups. Both groups were composed of 30 eyes. Group 1 - a semicircular frown incision with 4.0 mm chord length was made 1 mm posterior and most convex to limbus. Group 2 - a 3.2 mm straight incision was made 2 mm posterior to limbus. No-stitch was done in both groups. The corneal astigmatism was evaluated at postoperative 1st day, 1st week, 2nd week, 1st month, 2nd month and 3rd month with Bausch & Lomb keratometry, calculated by values derived from Cravy's vector method and statistically analyzed by Student t-test. RESULTS: The change of surgically induced astigmatism in group 1 was 0.52 D, 0.45 D, 0.43 D, 0.38 D, 0.40 D, and 0.39 D at 1st day, 1st week, 2nd week, 1st month, 2nd month, and 3rd month, respectively. In group 2, it was 0.83 D, 0.72 D, 0.65 D, 0.52 D, 0.50 D, and 0.49 D at the same intervals. These differences of astigmatic change were not statistically significant(p>0.05). CONCLUSION: The astigmatic change in a no-stitch frown incision with 4.0 mm chord length was not enough to comparable with that of a no-stitch 3.2 mm straight incision. We could safely use PMMA intraocular lens by no-stitch frown incision. So, this method has some advantages over small incision with foldable intraocular lens.