Corneal epithelial changes during midterm storage

The increased use of donor epithelium in keratoplasty for severe corneal disease has prompted an investigation of epithelial viability during midterm storage. Glycogen, ATP, and ADP have been used as indicators of the metabolic state of epithelial cells. These substances have been measured after conventional moist-chamber storage at 4 degrees C. for 1, 2, and 12 days and after immersion at 4 degrees C. in McCarey-Kaufman medium for 1, 2, and 12 days. In addition, recovery of glycogen and ATP stores has been evaluated after warming of the tissue in the storage solution to 37 degrees C. The evidence indicates that the corneal epithelium may recover these biologically important substances, despite depletion secondary to delayed cooling of donor eyes.