'Flawed' corneas safe for DSAEK, broadening donor pool

CHICAGO — Donor corneas with scarring, previous refractive surgery and other flaws provide safe and effective transplants for Descemet's stripping automated endothelial keratoplasty, a surgeon said here.

"We feel that the use of donor tissue with corneal scars and previous refractive surgery does not increase intraoperative or postoperative complications," Paul M. Phillips, MD, said. "Results at 6 months using flawed tissues are equivalent to the use of standard tissue, and therefore, we feel the use of this tissue in endothelial keratoplasty has expanded the donor pool."

At the annual meeting of the American Society of Cataract and Refractive Surgery, Dr. Phillips presented a retrospective review of DSAEK procedures and compared them to the Lions Eye Bank database to find procedures that used flawed donor corneas.

The researchers found 41 eyes that had reached at least 1 week of follow-up and 19 eyes that had reached 6 months of follow-up, he said. They then compared this group to a time-matched control group of 354 eyes that received standard donor corneal tissue during that same time period.

In the flawed group, there were 29 eyes with superficial anterior stromal scars, two with pterygium and 10 with previous corneal refractive surgery, but there were no significant preoperative differences between that group and the standard group, Dr. Phillips said.

At 1 week postop, neither group showed any intraocular complications, he said. Postoperatively, there were no immediate complications in the study group, but the control group had 10 dislocations.

Dr. Phillips then showed data looking at visual acuity, topography, astigmatism and pachymetry in eyes that had reached 6 months of follow-up.

"There is no statistically significant difference in any of these measurements at the 6-month time point," he said. "There was an improvement in overall best corrected visual acuity, as might be expected."

In the subset of tissue that previously underwent refractive surgery — five LASIK corneas and one cornea that received both LASIK and radial keratotomy — there were no significant differences, Dr. Phillips said.

"This is going to become more and more important, for as you know, over a million laser procedures are performed yearly in the United States," he explained.

In the discussion after his presentation, Dr. Phillips said intraoperative monitoring is important.

"We believe it is very important to check pachymetry if you're intraoperatively cutting and have the ability to manipulate the depth of your cut," he said.

Edward J. Holland, MD, who moderated the session, said, "I think it's great that we're using these corneas and we're not getting rid of them. I think we need a better term than flawed corneas because they're very good corneas."