Corneal preparation of eye bank eyes for experimental surgery

Purpose. To evaluate the efficacy of dextran in balanced salt solution (BSS ) as a preparation of eye bank corneas for experimental surgeries. Methods. We used 12 eye bank eyes that were unsuitable for transplant. The corneas were removed from the globe and affixed to a Hanna artificial anterior cham ber. Four concentrations of dextran-BSS (10%, 15%, 20%, and 30% [ 0.56%]) w ere used to dehydrate the corneas, and corneal thickness was assessed with an ultrasonic pachymeter (+/-5 mum) at varying time-intervals over 3 hours. Results. The corneas were thinned to an average thickness of 477 +/- 54 mu m, 430 +/- 54 mum, 406 +/- 61 mum, and 391 +/- 52 mum at average times of 7 5 +/- 0 minutes, 85 +/- 23 minutes, 60 +/- 12 minutes, and 45 +/- 0 minutes for the 10%, 15%, 20%, and 30% concentrations, respectively. Corneal thick ness was stabilized in both a 15% and a 20% solution. The data was fit to e xponential curves until a minimum value was reached, after which linear reg ression analysis was used to determine the slopes of the data. The slopes f or the 15% and 20% concentrations were not significantly different from 0 ( p = 0.5 and p = 0.4, respectively). The slopes for each set of data from th e 10% and 30% concentrations were significantly different from each other ( p = 0.010 and p = 0.001, respectively). Conclusions. A solution of 20% dext ran in BSS is effective for dehydrating eye bank corneas to a quasi-normal physiologic thickness and for maintaining the thickness for a sufficient am ount of time. Both the posterior and anterior sides of the cornea should be exposed to the solution for 60 minutes.