Trypan Blue Vital Dye Staining to Assess Endothelial Cell Viability in Donor Corneas

Objectives: To evaluate a simple intraoperative technique using trypan blue vital dye to assess endothelial cell viability in donor corneas and its role as an adjunct to conventional eye bank evaluation. Materials and Methods: Fifty consecutive donor corneas deemed suitable for transplantation based on eye bank-reported endothelial cell density (ECD) of > 2500 cells/mm 2 were evaluated. A 0.06% trypan blue solution was applied to the endothelial surface for 10 s, followed by rinsing with balanced salt solution. Areas of staining were interpreted as nonviable endothelium and graded based on the extent of involvement. Results: Despite acceptable ECD values, variability in endothelial viability was observed. Staining patterns were graded as minimal (<5%) in 14/50 (28%), mild (5% to <25%) in 22/50 (44%), moderate (25% to <50%) in 12/50 (24%), and severe (>50%) in 2/50 (4%) donor corneas. Staining predominantly involved the peripheral cornea, with relative central sparing in most cases. Donor tissues demonstrating severe staining were deemed unsuitable and returned to the eye bank. Conclusion: Trypan blue staining is a simple, rapid, and clinically useful adjunct for assessing endothelial viability in donor corneas. It may enhance tissue selection and help avoid the use of grafts with significant endothelial compromise.