Graft preparation for hemi-Descemet membrane endothelial keratoplasty (hemi-DMEK)

Abstract

Preparation of two hemi-DMEK grafts from one single human donor cornea is technically feasible, and the grafts can be stored after preparation in organ-culture similar to standard circular DMEK grafts. Hemi-DMEK may have the potential to double the availability of donor endothelial tissue for DMEK.

Impact of donor tissue diameter on postoperative central endothelial cell density in Descemet Membrane Endothelial Keratoplasty

“…The fact that 8‐mm grafts yielded similar ECD results as 10‐mm grafts suggests that more efficient use of tissues as suggested by the Melles group (Lie et al. ) could be a feasible approach in the future. However, the endothelial cell loss of smaller than 8‐mm grafts needs further evaluation.…”

“…In conclusion, our data suggest thatwithin limits yet to be definedlarger and smaller graft diameters can be used with similar results according to the surgeon's preference. The fact that 8-mm grafts yielded similar ECD results as 10-mm grafts suggests that more efficient use of tissues as suggested by the Melles group (Lie et al 2016) could be a feasible approach in the future. However, the endothelial cell loss of smaller than 8-mm grafts needs further evaluation.…”

A review of the evidence for in vivo corneal endothelial regeneration

“…The surface area of each piece is approximately equal to the conventional 9-mm DMEK graft, implying that the number of viable cells per graft is also approximately equal. 79 However, the semicircular hemi-DMEK will not match a 9-mm circular descemetorhexis. The widest points of the hemi-DMEK reach recipient endothelium peripherally; however, uncovered areas of bare stroma still remain.…”

Component corneal surgery: An update

“…Hemi-Descemet's membrane endothelial keratoplasty: The concept of using two endothelial grafts from one donor cornea was evaluated by lie et al . [ 82 ] This technique takes into consideration the substantial shortage of donor tissues for endothelial keratoplasty worldwide and evaluated the concept of using two endothelial grafts from one donor cornea, which may potentially increase the pool of suitable donor tissues for DMEK. [ 82 ] In an experimental study including 10 human corneas, the authors could successfully obtain two DMEK grafts with a different (semi-circular) shape (hemi-DMEK), but similar surface area as a “conventional” 8–9 mm circular transplant from a single donor cornea.…”

“…[ 82 ] This technique takes into consideration the substantial shortage of donor tissues for endothelial keratoplasty worldwide and evaluated the concept of using two endothelial grafts from one donor cornea, which may potentially increase the pool of suitable donor tissues for DMEK. [ 82 ] In an experimental study including 10 human corneas, the authors could successfully obtain two DMEK grafts with a different (semi-circular) shape (hemi-DMEK), but similar surface area as a “conventional” 8–9 mm circular transplant from a single donor cornea. They concluded that preparation of two hemi-DMEK grafts from one single human donor cornea is technically feasible, and the grafts can be stored in organ-culture medium similar to the standard circular DMEK grafts.…”