Manual adjustment of specular images: Correcting what the computer can't see after DMEK

Abstract

Purpose : To analyze a single clinical site's method for capturing endothelial cell density (ECD) and endothelial cell loss (ECL) by an automated method with manual correction (AMMC) of specular microscopy images in postop DMEK patients against the Konan center method.

Methods : A consecutive series of fifty nine patients who underwent DMEK surgery, and who had central donor graft as well as central 6 and 12 months post-surgery specular microscopic images available were retrospectively identified. Specular microscopic images of the central endothelium were first evaluated in the clinic using the AMMC by a technician. Images were then masked and provided to the Cornea Image Analysis Reading Center (CIARC) for analysis using the Konan center method by certified readers using a dual grading and adjudication process.

Results : At 6 Months postop the AMMC method was strongly correlated with the Konan center method (r=0.92, p<0.001). We found a mean ECD of 1939 ± 407 cells/mm² and 1949 ± 437 cells/mm² for the AMMC method and the Konan center method respectively (p=0.67). At 12 Months postop the AMMC method was strongly correlated with the Konan center method (r=0.92, p<0.001). We found a mean ECD of 1843 ± 435 cells/mm² and 1833 ± 470 cells/mm² for the AMMC method and the Konan center method respectively (p=0.63). Between 6 and 12 months, we observed an average of 4 and 6 percent endothelial cell loss for this group when evaluated using the AMMC and Konan center methods respectively. No statistically significant difference was observed between the 2 methods for percent endothelial cell loss (p=0.36).

Conclusions : We found high levels of correlation between endothelial cell densities when comparing an automated method with manual correction to the standard Konan center method. Additionally, each method provided equivalent amounts of percent endothelial cell loss between 6 and 12 months. Our results suggest that as long as a consistent method for evaluating endothelial cell density is used, surgeons can accurately evaluate their percent endothelial cell loss post DMEK transplant.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.