Abstract
Purpose: :
To measure changes in total corneal, host, and graft thicknesses after Descemet-stripping with endothelial keratoplasty (DSEK), and to assess relationships between these thicknesses, vision, and forward light scatter.
Methods: :
Forty-one eyes of 36 patients with Fuchs’ endothelial dystrophy were examined before and at 1, 3, 6, and 12 months after DSEK in a prospective, observational study. All eyes were pseudophakic postoperatively. At each visit, corneas were examined by confocal microscopy (ConfoScan 4 with z-ring adapter, Nidek Technologies) and central total corneal, host, and graft thicknesses were measured from the confocal intensity profile. High contrast visual acuity (HCVA) was measured by using the electronic-ETDRS protocol, and forward light scatter was measured by using a straylight meter as the logarithm of the straylight parameter (log s). Changes in thicknesses, HCVA, and scatter were assessed by using generalized estimating equation models to account for possible correlation between fellow eyes of the same subject; p-values were adjusted for multiple comparisons.
Results: :
Total corneal thickness was 610 ± 50 µm (mean ± SD) before DSEK, increased to 682 ± 74 µm by 1 month (p<0.001), and stabilized at 658 ± 69 µm by 3 months (p=0.05 vs. 1 month). Host corneal thickness was 571 ± 49 µm before DSEK, decreased to 511 ± 42 by 1 month (p<0.001) and remained stable through 12 months (501 ± 36 µm; p=0.36 vs. 1 month). Graft thickness was 171 ± 57 µm at 1 month, decreased to 155 ± 49 µm by 3 months (p=0.01), and then remained stable through 12 months (154 ± 54 µm; p=0.99 vs. 3 months.) Graft thickness ranged from 82 µm to 340 µm at 3 months. HCVA was 0.44 ± 0.21 logMAR before DSEK, improved to 0.26 ± 0.20 logMAR by 3 months (p<0.001), and improved to 0.18 ± 0.16 logMAR at 12 months (p<0.001 vs. 3 months). HCVA did not correlate with corneal, host or graft thickness after DSEK. Forward scatter improved from 1.41 ± 0.17 log s at 1 month to 1.36 ± 0.22 log s at 3 months (p=0.03) and then remained stable through 12 months (1.36 ± 0.21 log s, p=0.99).
Conclusions: :
Total corneal thickness stabilizes by 3 months after DSEK. Thinner grafts are not associated with better HCVA after DSEK. The continued improvement in HCVA beyond 3 months is not associated with changes in thickness or forward scatter.
Keywords: cornea: clinical science • transplantation • clinical (human) or epidemiologic studies: outcomes/complications