PURPOSE: This study was conducted to compare post-operative astigmatic outcomes of two groups, with-the-rule (WTR) and against-the-rule (ATR) astigmatism patients, according to the haptic axis of intraocular lenses (IOLs) inserted in cataract surgery. METHODS: Seventy-two eyes with WTR astigmatism and 79 eyes with ATR astigmatism had cataract surgery through a clear corneal temporal incision. These two groups of eyes were then each divided into 2 groups based on whether the haptic axis of the inserted IOL was at 180degrees or 90degrees. For ATR patients, the outcomes were analyzed according to the three types of IOLs. RESULTS: There was no difference in corneal astigmatism, but WTR patients with a 180degrees haptic axis of the inserted IOL and ATR patients with a 90degrees hepatic axis of the inserted IOL had a significant decrease in postoperative refractive astigmatism (p < 0.05). The changes in ATR astigmatism according to the IOL type were more effective in single-piece acrylic IOLs than in the three-piece polymethylmethacrylate haptic IOL group. CONCLUSIONS: Insertion of the IOL at the 180degrees haptic axis in WTR patients and at 90degrees in ATR patients during cataract surgery may have an effect in reducing pre-existing astigmatism. This observed effect was not consistent among the different types of IOLs.
Astigmatism/classification/*etiology/*physiopathology ; Cataract Extraction/*adverse effects ; Equipment Design ; Humans ; Lens Implantation, Intraocular/*methods ; *Lenses, Intraocular ; *Postoperative Complications ; Treatment Outcome