Abstract
Purpose :
Descemet membrane endothelial keratoplasty (DMEK) rapidly deturgesces a cornea that is edematous due to endothelial dysfunction. In some cases, the central cornea deturgescense reveals localized posterior corneal steepening similar to that of keratoconus. Our aim was to describe changes in corneal thickness and identify the incidence of posterior corneal changes characteristic of keratoconus after DMEK surgery.
Methods :
A retrospective chart review was conducted for 50 eyes that received cataract surgery and 50 eyes that received DMEK for Fuchs’ Dystrophy. 6 month and 1 year follow-up images were reviewed for the DMEK group using an Oculus Pentacam. The central corneal thickness (CCT) of the preoperative cataract surgery eyes served as normal controls and was compared to the CCT of the postoperative DMEK eyes at 6 months and 1 year. Pentacam images in the DMEK group were also reviewed for characteristics resembling keratoconus. Statistical significance comparing CCT was determined using the Student’s T-test.
Results :
The normal CCT from 50 eyes at our center was 543µm±35µm. The 6 month postoperative CCT in the DMEK group was 534µm±35µm (P=0.23) and the 1 year CCT was 536µm±35µm (P=0.33). 19 out of 50 DMEK eyes (38%) had posterior steepening resembling keratoconus at the 6 month visit. A subgroup analysis of the preoperative CCT from those 19 eyes vs 31 eyes without keratoconus-like changes was not statistically different (611µm±51µm vs 615µm±56µm, P=0.80). All 19 of those eyes had the same posterior corneal changes at the 1 year visit.
Conclusions :
CCT after DMEK was not statistically different compared to normal corneas at 6 months and 1 year postoperative. The posterior corneal steepening seen in 38% of DMEK corneas may be a consequence of stromal keratocyte apoptosis due to chronic edema. The localized steepening persists out to 1 year postoperative, suggesting that there may be structural loss in the stroma.
This is a 2021 ARVO Annual Meeting abstract.