ASCRS 2023: Wills Eye Hospital research on corneal swelling and dynamics during corneal collagen crosslinking

Zeba Syed, MD, from Wills Eye Hospital discussed their research on corneal swelling and dynamics during corneal collagen crosslinking at the 2023 ASCRS annual meeting in San Diego.

Video transcript

Editor’s note: Transcript lightly edited for clarity.

Zeba Syed, MD:

Hi, everyone. My name is Zeba Syed. I'm on the cornea service at Wills Eye Hospital, and I'm really excited to be here presenting at ASCRS some of our research on corneal swelling and dynamics during corneal collagen crosslinking. So this is a study the background of which came about when I was thinking about which patients are candidates and not candidates for crosslinking.

So crosslinking is a procedure we do for progressive keratoconus and it stabilizes the cornea so patients don't continue to get worse. It's a great option for patients with keratoconus, because it prevents them from going on and needing corneal transplants. But the limitation is that patients whose corneas are too thin—so basically more advanced cases of keratoconus—may not be candidates for crosslinking.

The goal of this study was basically twofold. We recruited a group of patients with thinner corneas at baseline, all of whom required intraoperative swelling during the procedure. We wanted to understand first, could we get all of them to over 400 microns, which is kind of the threshold to proceed with the UV light treatment. So one, we get them all above the 400 micron threshold and two, what factors were associated with the rate of swelling. So those were the two questions we sought to answer.

So regarding the first question, we found that we were able to swell all of our corneas. We had over 30 patients in the study. We were able to swell all the corneas to over 400 microns. We did find that the thinner corneas, the ones that were, the half that were on the thinner side, took a little longer to swell to over 400. So that took about 8 minutes compared to 6 minutes for the other (the thicker), but still all of them were able to get swolllen to above 400 microns.

Regarding the second question, the factors associated with the rate of swelling... Overall, the rate of growth was about 10 microns per 30 seconds for all the corneas in our study. We did find that patients with thicker corneas at baseline swelled quicker, probably due to the kind of the more sponginess or less to see of the cornea. This data can kind of help surgeons plan the timing of their procedure and kind of get a sense of how long it will take to do the crosslinking. So those are the findings of our study. We hope you listen to our presentation and read the results of manuscripts.