Abstract
Purpose: :
To compare whole eye high-order aberrations (HOAs) between pseudophakic eyes after Descemet-stripping with endothelial keratoplasty (DSEK) and pseudophakic eyes with otherwise normal corneas.
Methods: :
Whole-eye wavefront errors were measured by using a Hartmann-Shack aberrometer (VISX Wavescan) in 16 eyes at 6 months, 17 eyes at 12 months, and 11 eyes at 24 months after DSEK. In all cases, DSEK was performed for Fuchs’ dystrophy through a 5-6 mm scleral incision, and the graft was prepared with a microkeratome. All DSEK eyes were pseudophakic, and were compared to 27 pseudophakic eyes (with otherwise normal corneas) implanted with the same type of intraocular lens. High-order aberrations were calculated over a 3-mm pupil and decomposed into Zernicke polynomials to the 6th order. Low-contrast visual acuity (LCVA) was measured by using a 10% ETDRS chart under photopic conditions (screen brightness, 139 cd/m2). HOAs were compared between DSEK and pseudophakic eyes by using generalized estimating equation models to account for possible correlation between fellow eyes of the same subject.
Results: :
The aberrometer could not acquire data in 5 eyes at 6 months, 4 eyes at 12 months, and 1 eye at 24 months after DSEK. Total HOAs in the remaining DSEK eyes at 6 months (0.14 ± 0.05 µm; n=11; root-mean-square wavefront error), 12 months (0.13 ± 0.05 µm; n=13), and 24 months (0.13 ± 0.06 µm; n=10) were higher than in healthy pseudophakic eyes (0.07 ± 0.04 µm, n=27; p≤0.003). Total HOAs at 6 months after DSEK did not differ from those at 24 months (p=0.62). Trefoil was higher in eyes after DSEK at 6 months (0.09 ± 0.04 µm), 12 months (0.08 ± 0.04 µm), and 24 months (0.09 ± 0.06 µm; n=10), than in pseudophakic eyes (0.04 ± 0.02 µm; p≤0.004). HOAs did not correlate with LCVA within the DSEK group, but when DSEK and healthy pseudophakic eyes were combined, total HOAs correlated with LCVA at 6 months (r=0.58, p<0.001, n=38), 12 months (r=0.35, p=0.01, n=40), and 24 months (r=0.34, p=0.03, n=37).
Conclusions: :
Total HOAs and trefoil are higher in pseudophakic eyes after DSEK than in pseudophakic eyes with otherwise normal corneas. The differences in high-order aberrations can be attributed to the optical properties of the cornea after DSEK, possibly the posterior graft surface. Increased HOAs after DSEK might contribute to decreased vision.
Keywords: cornea: clinical science • transplantation • aberrations