Fewer tears for SCUBA than Muraine in DMEK graft prep

The submerged cornea using backgrounds away (SCUBA) peeling technique may be more effective than the newer Muraine technique for preparing endothelial donor grafts for Descemet membrane endothelial keratoplasty (DMEK), according to a study published in Cornea.

Researchers from the Department of Ophthalmology, Queen's University, Kingston, ON, Canada, and the University of Ottawa Eye Institute, Ottawa, ON, Canada conducted a prospective ex vivo investigation in a wet-lab setting. The Muraine technique was used to prepare 20 donor corneas for DMEK - 10 of the donor grafts were prepared by a corneal fellow and 10 were prepared by a corneal surgeon. Likewise, 20 donor corneas were prepared for DMEK using the SCUBA technique; again, 10 were prepared by a corneal fellow and 10 were prepared by a corneal surgeon. As the Muraine technique is newer and therefore likely less familiar to the fellow and surgeon, they both performed 10 “practice” procedures using the Muraine technique before starting the study.

The researchers examined the time needed to prepare endothelial grafts and the number of graft tears.

For both the surgeon (301 ± 85 seconds) and the fellow (523 ± 58 seconds), the SCUBA technique had a shorter median time to prepare the grafts than the Muraine technique (359 ± 83 seconds for the surgeon; 543 ± 44 seconds for the fellow). The findings, however, were not statistically significant. 

There was a statistically significant difference in the number of graft tears. There were 5 graft tears (2 by the surgeon, 3 by the fellow), when using the Muraine technique, compared to 0 graft tears when using the SCUBA technique.

“Given the incidence of graft tears in the Muraine group and the need for specialized equipment (the Muraine punch), we conclude that the SCUBA technique may be superior for the preparation of endothelial donor grafts for DMEK,” the researchers wrote. “However, with further refinement, this new technique has the potential to be a reliable alternative method.”