2011 Volume 32 Issue 3 Pages 59-66
Purpose: To compare postoperative uncorrected visual acuity (UCVA) between against-the-rule (ATR) and with-the-rule (WTR) astigmatism.
Methods: UCVA in far vision was measured in two groups of postoperative astigmatics at −1diopter (D) who had undergone keratorefractive surgery in 2008. One group had WTR axis at 0±15 degrees (171 eyes), the other had ATR axis at 90±15 degrees (124 eyes). The best UCVA (logMAR) was compared between the two groups.
Results: The spherical equivalent yielding the best UCVA of the groups was (−0.25±0.5D) for WTR and (+0.25±0.5D) for ATR. The mean and 95% confidence interval of the best logMAR of the groups were, respectively (−0.152 and −0.170 to −0.133) in WTR and (−0.168 and −0.190 to −0.146) in ATR. The difference was not statistically significant (p=0.294) and was clinically negligible.
Conclusions: The best UCVAs in postoperative astigmatism of WTR and ATR are the same, whereas the spherical equivalents yielding the best UCVA differ between the groups.
