Abstract
Purpose :
DMEK is the preferred surgical treatment for endothelial diseases such as Fuchs’ dystrophy and bullous keratopathy. However, intraocular unscrolling of DMEK grafts can be challenging, particularly with younger donor tissue (age <50). Paired radial incisions, placed 4 clock hours apart, have been used to ease unscrolling in young donor tissue by encouraging grafts to adopt an open triple scroll conformation rather than a natural double or single scroll. However, for tissue from donors <65 years old, only 75% of grafts with incisions form a stable triple scroll. No study has examined why all grafts do not form a triple scroll. Recent studies found that DMEK grafts preferentially scroll around the superior-inferior axis, suggesting that graft scrolling behavior can be predicted by orientation. The purpose of this study was to evaluate whether placement of paired incisions relative to the preferential graft scrolling axis affects the ability of the graft to form a triple scroll.
Methods :
The effect of paired incision orientation relative to the scrolling axis on triple scroll formation was examined in young donor tissue through in vitro testing and DMEK surgery observations. For in vitro testing, paired radial incisions were placed on either the S-I axis (at 10 & 2 or 4 & 8 o’clock) or N-T axis (at 2 & 4 or 8 & 10 o’clock) in mated pairs of grafts with donor age ≤65. Triple scroll formation was compared between groups after grafts were submerged in saline and encouraged to triple scroll. Surgical videos from DMEK cases with young donor grafts (age ≤50) were also reviewed. Triple scroll formation and unscrolling times were compared for grafts with S-I incisions vs. N-T incisions.
Results :
In total 12 DMEK grafts (6 mated pairs) were used for in vitro testing. A preference for triple scroll formation was demonstrated in grafts with N-T vs. S-I incisions (83% vs. 50%). Surgical video review of 6 DMEK cases (3 N-T grafts, 3 S-I grafts) similarly demonstrated a preference for triple scroll formation in N-T vs. S-I incisions (100% vs. 67%). There was no statistically significant difference in mean unscrolling times between the groups (5:10min vs 4:26min, p=0.714).
Conclusions :
Adding paired incisions to the N-T axis of DMEK grafts may improve the likelihood of obtaining a triple scroll and help reduce difficulty of DMEK surgery with young donor tissue.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.