Striving to improve outcomes is important because of the negative effect of astigmatism on patients’ vision postoperatively.
Spanish researchers who compared 2 techniques to address moderate astigmatism found that implantation of a toric intraocular lens (IOL) corrected a greater degree of astigmatism than femtosecond laser-assisted arcuate keratotomy.
However, the laser procedure is safe and should be considered to correct corneal astigmatism, according to Ruben Hernandez, MSc, and colleagues from the Department of Ophthalmology, Miguel Servet University Hospital, and the Miguel Servet Ophthalmology Research Group, Aragon Health Research Institute, Zaragoza, Spain.
Striving to improve outcomes is important because of the negative effect of astigmatism on patients’ vision postoperatively. The investigators pointed out that 1 diopter (D) of uncorrected astigmatism can decrease vision by 1.5 lines and they estimated that 35% of patients with cataracts have corneal astigmatism exceeding 1 D and 20% have more than 1.5 D of corneal astigmatism.
With that in mind, they performed a prospective randomized study1 that included 75 eyes of 67 patients who had age-related cataracts and moderate corneal astigmatism ranging from 1.25 to 3 diopters. The patients were randomized to undergo either implantation of a toric IOL or femtosecond laser-assisted arcuate keratotomy to correct the astigmatism and followed at 1 and 3 months postoperatively.
Comparison of the procedures
The results showed that 3 months postoperatively, the toric IOL group had significantly (p = 0.37) lower mean residual refractive astigmatism (-0.63 ± 0.55 D) compared with the laser group (-0.90 ± 0.53 D). The residual astigmatism was 1 D or lower in 84% of eyes in the toric IOL group and in 64% of the eyes in the laser group.
No significant differences were seen between the 2 groups in difference vector, angle error, magnitude error, or correction index in the 3-month evaluation. The index of success (IS) was 0.32 ± 0.33 D in the toric IOL group and 0.48 ± 0.29 D in the laser group (p = 0.029).
The investigators concluded that implantation of a toric IOL continues to be the procedure of choice to correct moderate astigmatism after cataract surgery. However, the laser procedure is safe and also should be considered for these patients despite the fact that it is not as predictable as the toric IOL procedure.