LAUSR

Purpose The organ culture (OC) is a passive corneal storage, gold standard in Europe for decades. The bioreactor (BR) is a sterile transparent device that allows active storage: transcorneal pressure gradient and fluid renewal. Aim: To compare quality of human corneas stored for 1 month in our BR versus (vs) OC. Methods Randomized controled preclinical study, authorized by the French Biomedicine Agency and an IRB, including only fresh scientific paired human corneas >2000cells/mm2 and <10% difference between both corneas at day (D)2. Immediately at retrieval, one cornea was randomized and stored in OC and the other in BR, both with the same commercial medium (CorneaMax). At D26 only OC corneas were transferred to a deswelling medium (CorneaJet). We calculated that 49 pairs were needed to show a difference of 500 viable cells/mm2 between groups. Assessments were performed at D2, 26, 28. Main criterion: viable ECD (vECD) determined by triple staining Hoechst/Ethidium/Calcein at D28, blind of storage method. Secondary criteria: average transparency (T), central corneal thickness (CCT) and microbiology. Results We retrieved 60 pairs, included 52 pairs at D2, analyzed 50 pairs (1 contamination per group). At D2 ECD in BR was 2607±340 vs 2576±357cells/mm2 in OC (p=0.243). At D26 ECD was >2000cells/mm2 for 92% of corneas in BR vs 58% in OC (p 2000 viable cells/mm2 in BR vs 22% in OC (p<0.001); T didn't differ and CCT was higher in BR with 684±52 vs 608±53μm in OC (p<0.001). Conclusions Restoring IOP and renewing medium significantly improves endothelial cell survival while avoiding deleterious deswelling necessary in OC: after 1 month-storage, the BR provides much more corneas suitable for transplantation and higher quality grafts that could survive longer in recipients.