Abstract
Purpose :
To identify factors associated with changes in long term refractive outcomes after toric intraocular lens implantation.
Methods :
We conducted a retrospective chart review of cataract surgeries at a single US Veterans Hospital. Study inclusion required uncomplicated posterior chamber Alcon SN6ATT toric intraocular lens (IOL) placement from 2010 –2017 and refractions 1 month and 5 years after surgery. Exclusion criteria were sulcus IOL placement, subsequent intraocular or refractive surgery in the operative eye, and 5-year Snellen visual acuity of 20/60 or worse. Outcomes of interest were change in spherical equivalent (ΔSEQ) and change in magnitude of the astigmatism vector (Δρ) from the 1-month to 5-year refractive measurement. In patients with both eyes meeting study criteria, only the eye with the larger ΔSEQ or larger Δρ was included. Factors analyzed as predictors included age, sex, race, pseudoexfoliation (PXF) syndrome, axial length (AL), pre-operative difference between horizontal and vertical keratometry measurements (ΔK), IOL power, neodymium:yttrium-aluminum-garnet (Nd:YAG) capsulotomy, and intravitreal injections. Significant predictors in the univariable outcome analyses (P<0.1) were further analyzed with multiple linear regression.
Results :
Of the 256 patients (320 eyes) meeting study criteria, the mean ± standard deviation age at the time of surgery was 70.9 ± 8.5 years. Multiple linear regression analysis identified AL (p=0.018) and ΔK (p=0.002) as significant predictors of Δρ, with more change in astigmatism seen in shorter eyes and eyes with larger ΔK. We identified IOL power (p=0.048) and PXF syndrome (p=0.045) as predictors of ΔSEQ. Lower IOL power was associated with myopic shift. Higher IOL power and PXF syndrome were associated with hyperopic shift.
Conclusions :
Shorter AL, larger ΔK, and PXF syndrome are independent predictors for long term refractive change after toric IOL implantation.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.