Comparison of grafted and non-grafted patients with corneal astigmatism undergoing cataract extraction with a toric intraocular lens implant.

Background: Toric intraocular lenses (IOLs) are advocated as an effective treatment for both regular corneal-based astigmatism and cataract in both non-penetrating keratoplasty and penetrating keratoplasty (PK) patients. The aim of this analysis is to compare postoperative outcomes for both PK and non-PK patients to determine whether or not the past PK is relevant when calculating the appropriate IOL and predicting the postoperative results.

Methods: A retrospective analysis was performed on 14 non-PK and eight PK patients who underwent cataract surgery and astigmatism correction with a Rayner toric IOL. Preoperatively, best spectacle-corrected visual acuity, biometry and refractive data were recorded. Postoperative analysis at 1 month looked at best-uncorrected visual acuity (BUVA), refractive data and IOL axis. Statistical analysis was undertaken to test for differences in outcomes between the PK and non-PK groups.

Results: Preoperatively, a significant difference was seen between cylinder and astigmatism and not between sphere, axial length or anterior chamber depth. Analysis of preoperative best spectacle-corrected visual acuity, IOL error predictability, IOL rotational stability and refractive outcomes revealed no difference between PK and non-PK groups, but a significant difference was seen postoperatively with PK patients having worse BUVA.

Conclusion: Toric IOLs are an effective means for treating both regular corneal-based astigmatism and cataract in both PK and non-PK patient groups. Analysis of results revealed similar trends for both groups in all areas except postoperative BUVA. Further studies are planned to better understand why PK patient's BUVA did not fit the trend of the other results.