Relaxing Hinges
DMEK Graft Processing
Tissue can now be prepared with “relaxing hinges,” a pair of small incisions added to a Descemet’s Membrane Endothelial Keratoplasty (DMEK) graft.
To improve the handling of DMEK grafts, we partnered with local surgical innovator, Dr. Mark Hansen, to add precision cuts to the graft edge. This alteration to the normally tightly-scrolled graft encourages the formation of a “Tri-Fold” (Fig 1) that is wider and easier to open and place in the eye. Lions Gift of Sight researchers investigated the effect of this graft alteration and found it shortens the learning curve for DMEK surgeons and makes this difficult surgery easier for all to perform.
Fig 1. A comparison of tissue scrolling for various endothelial grafts in balanced salt solution. (A) DSAEK [147µm], (B) NT-DSAEK [29 µm], (C) pre-Descemet endothelial keratoplasty (PDEK) graft [37µm], and (D) DMEK [15 µm]. Note that with NT-DSAEK (B), the tissue keeps its anatomical shape like a standard DSAEK, despite being closer in thickness to PDEK (C) and DMEK (D). This makes it easier to adhere to a receipt’s eye during the transplant.
Lions Gift of Sight's Research & Development Department validated that these incisions are safe to add and find that they help reduce surgical times, especially for new DMEK surgeons. Lions Gift of Sight was the first eye bank to provide "pre-hinged" tissue.
Article in Healio: Ocular Surgery News May 10, 2019 Authors Hardten and Hansen
Small relaxing incisions may allow easier DMEK surgery
Article in CORNEA 2021 Jan;40(1):99-106
Ex Vivo Safety and Efficacy of Paired Peripheral Incisions in Descemet's Membrane Endothelial Keratoplasty Grafts to Facilitate Unscrolling
U.S. Patent No. 12,257,365 B2