Toric phakic implantable collamer lens for correction of astigmatism: 1-year outcomes

Erik L Mertens
Medipolis Eye Centre, Antwerp, Belgium

Purpose: The purpose of this study was to assess predictability, efficacy, safety and stability in patients who received a toric implantable collamer lens to correct moderate to high myopic astigmatism.
Methods: Forty-three eyes of 23 patients underwent implantation of a toric implantable collamer lens (STAAR Surgical Inc) for astigmatism correction. Mean spherical refraction was —4.98 ± 3.49 diopters (D) (range: 0 to —13 D), and mean cylinder was —2.62 ± 0.97 D (range: —1.00 to —5.00 D). Main outcomes measures evaluated during a 12-month follow-up included uncorrected visual acuity (UCVA), refraction, best-corrected visual acuity (BCVA), vault, and adverse events.
Results: At 12 months the mean Snellen decimal UCVA was 0.87 ± 0.27 and mean BCVA was 0.94 ± 0.21, with an efficacy index of 1.05. More than 60% of the eyes gained ≥1 line of BCVA (17 eyes, safety index of 1.14). The treatment was highly predictable for spherical equivalent (r² = 0.99) and astigmatic components: J₀ (r² = 0.99) and J₄₅ (r² = 0.90). The mean spherical equivalent dropped from —7.29 ± 3.4 D to —0.17 ± 0.40 D at 12 months. Of the attempted spherical equivalent, 76.7% of the eyes were within ±0.50 D and 97.7% eyes were within ±1.00 D, respectively. For J₀ and J₄₅, 97.7% and 83.7% were within ±0.50 D, respectively.
Conclusion: The results of the present study support the safety, efficacy, and predictability of toric implantable collamer lens implantation to treat moderate to high myopic astigmatism.

Keywords: phakic intraocular lens, toric implantable collamer lens, astigmatism