Comparison of refractive stability after non-toric versus toric intraocular lens implantation during cataract surgery

To compare refractive state changes in eyes implanted with toric intraocular lenses (IOLs) vs non-toric IOLs, after cataract extraction.

Retrospective, comparative.

In a single institution, 121 eyes underwent phacoemulsification and implantation with either non-toric IOLs or toric IOLs. The spherical value, cylindrical value, spherical equivalent (SE) of refractive error, and visual acuity were measured preoperatively and 1, 3, and 6 months after surgery. Main outcome measures were the pattern of changes of spherical, cylindrical, and SE values based on postoperative time, between different IOL types.

The groups, which included patients who underwent surgery with SN60WF (Group I), SA6AT3 (Group II-3), SA6AT4 (Group II-4), and SA6AT5 lenses (Group II-5), contained 37, 29, 23, and 32 eyes, respectively. The cylindrical value was significantly decreased in all groups (P < .05). Before surgery, the SE of refractive errors was estimated as -0.21, -0.10, -0.20, and -0.22 in the respective groups. The actual remaining SE values were -0.19, -0.24, -0.42, and -0.56 at 1 month; -0.17, -0.26, -0.57, and -0.64 at 3 months; and -0.17, -0.26, -0.70, and -0.74 at 6 months postoperatively, respectively. The follow-up SE values in groups I and II-3 were similar (P > .05 in both groups); however, significant myopic changes were observed in Groups II-4 and II-5 after surgery, vs Group I (P < .05).

Selection of toric IOLs for cataract surgery requires a refined formula to precisely determine necessary IOL power, especially in cases with high levels of astigmatism, to reliably and accurately prevent myopic outcomes.