Donor Endothelial Specular Image Quality in Optisol GS and Life4˚C

PURPOSE: Identify warming time needed to obtain analyzable specular endothelial images in Optisol GSand Life4 ̊C-stored corneas and identify other factors that contribute to endothelial image quality. METHODS: Twenty-five transplant quality human corneal donor pairs were obtained. One cornea was placed in Optisol GS, the other in Life4 ̊C, in their respective viewing chambers, and both were stored at 2°C to 8°C for 48 hours. Specular microscopic images of the central endothelium were then obtained immediately following placement at room temperature, and additional images were taken every 30 minutes for a total of 3 hours. Image quality was graded by a single masked reader using a 6-point scale; an analyzable image was defined as grade >3. RESULTS: Internal chamber temperature reached room temperature at 1.5 hours for both groups. The Optisol GS group had a higher average image grade than the Life4°C group at all time points; however, this difference was only significant at 1.5 hours and 2 hours: 2.8 ± 1.6 (SD) for Optisol GS versus 2.1± 1.1 for Life4°C at 1.5 hours (P=0.007), and 3.5 ± 1.5 versus 2.8 ±1.1 at 2 hours (P=0.007). Average image grade became analyzable at 2 hours for Optisol GS (3.5 ± 1.5) and at 2.5 hours for Life4°C (3.2 ± 1.1). Donor age and death–to-preservation time were not found to affect image quality. CONCLUSIONS: Optisol GS-stored corneas should be warmed at room temperature for at least 2 hours, while Life4°C at least 2.5 hours, to achieve a good-to-excellent quality specular image of the donor endothelium.