Graft Thickness at 6 Months Postoperatively Predicts Long-Term Visual Acuity Outcomes of Descemet Stripping Automated Endothelial Keratoplasty for Fuchs Dystrophy and Moderate Phakic Bullous Keratopathy: A Cohort Study

Abstract

Purpose: It remains unclear whether preoperative central graft thickness (CGT) contributes to visual outcomes of Descemet stripping automated endothelial keratoplasty (DSAEK). This retrospective cohort study examined the ability of preoperative and postoperative CGT to predict 12-month best spectacle-corrected visual acuity (BSCVA) after DSAEK for Fuchs endothelial corneal dystrophy/moderate pseudophakic bullous keratopathy/second graft.Methods: All consecutive patients who underwent DSAEK in 2015 to 2018 were included. The primary end point was 12-month BSCVA. DSAEK-CGT was measured preoperatively and 6 times between postoperative day 8 and month 12. Eyes were divided according to preoperative CGT 130 mm (ultrathin-DSAEK threshold) or 6-month postoperative CGT 100 mm (mean 6-month postoperative DSAEK-CGT). The t test assessed CGT evolution of the 4 groups over time. Multivariate analyses examined whether preoperative CGT or 6-month CGT categories predicted 12-month BSCVA. Multivariate analysis assessed the preoperative/ perioperative factors that predicted 6-month CGT.Results: A total of 108 eyes (68 patients) underwent DSAEK.Preoperative CGT was .130 and #130 mm in 87 and 21 eyes, respectively. Postoperative CGT was .100 and #100 mm in 50 and 58 eyes, respectively. Thin 6-month postoperative grafts thinned significantly more relative to preoperative thickness than thick grafts (P , 0.001). Preoperative CGT subgroups did not show this difference. Six-month postoperative CGT (P = 0.01), but not preoperative CGT, predicted 12-month BSCVA. Preoperative CGT strongly predicted 6-month CGT (P = 0.0003). Conclusions:Postoperative, but not preoperative, DSAEK-CGT predicted 6-month BSCVA. The correlation between preoperative and postoperative CGT and interstudy variation in preoperative CGT measurement accuracy may explain literature disparities regarding the importance of preoperative CGT in DSAEK outcomes.

Identification of the preoperative and perioperative factors that predict postoperative endothelial cell density after Descemet membrane endothelial keratoplasty: A retrospective cohort study

“…This may reflect, at least in part, differences between the study populations in terms of surgical practice, variable measurement, postoperative timepoint, and study/statistical design. It is also possible that significantly-associated pre/perioperative variables relate only indirectly to the fundamental endothelial cell variable(s) that ultimately shape(s) the postoperative density and function of these cells [ 55 , 56 ].…”

Postoperative, but not preoperative, central corneal thickness correlates with the postoperative visual outcomes of Descemet membrane endothelial keratoplasty

“…Therefore, we suggested that the variable CGT-BSCVA relationships reported in the literature may reflect inaccuracies or variation in the preoperative CGT measurements due to various factors (e.g. graft culture duration) that blur the relationship between CGT and visual acuity; these factors disappear after surgery, allowing the intrinsic relationship between CGT and BSCVA to emerge [30]. Our explorations in the present study suggested that a similar phenomenon may be operating in the relationship between CCT and BSCVA in DMEK: we found that unlike preoperative CCT, postoperative CCT did correlate significantly with final BSCVA.…”

“…Another possibility is suggested by our earlier study on the relationship between central graft thickness (CGT) and final BSCVA after DSAEK [30]. Whether thinning DSAEK grafts actually improves visual outcomes has been a vexed question in the literature, with some studies [31][32][33][34][35][36] but not others [37][38][39][40][41][42][43][44] finding an effect.…”