[Comparing cryopreserved with fresh corneas on clinical application in penetrating keratoplasty].
To evaluate the role of cryopreserved corneas on penetrating keratoplasty (PKP) by comparing them with fresh corneas on clinical application. Third-six excellent condition patients were chosen and randomly divided into two groups. They were performed PKP by using fresh and cryopreserved corneas respectively. The graft transparency, epithelial healing speed of graft, tear membrane, graft thickness, endothelium density and visual acurity were emphasized respectively. When fresh and cryopreserved corneas were used on PKP as the donor respectively, postoperative time to recover normal break-up time (BUT) was two to six months average (4.7 +/- 0.3) months and two to eight months, average (5.6 +/- 0.4) months and time to recover normal Schirmer's test was one to four months average (2.1 +/- 0.3) months and 1-3.5 months, average (1.7 +/- 0.5) months. The graft's thickness, stabilized visual acurity and graft's rejective rate were 0.56-0.68 mm (average 0.62 mm) vs 0.54-0.62 mm (average 0.59 mm), (0.46 +/- 0.03) vs (0.44 +/- 0.05) and 20% vs 19% respectively when fresh vs cryoperserved corneas. No statistical significance between fresh and cryopreserved corneas (P > 0.05). But the grafts behaved intact epithelium and continuing transparency when fresh corneas as donors, while the graft's epithelial defects healed after three to five days of the operation and edematous grafts were reclear after two to three weeks of the operation when cryopreserved corneas as donors. Graft's endothelium density in fresh corneas group 2,043-2,210 cells/mm2 (average 2,135 cells/mm2) was high than in cryopreserved corneas 1,240-1,860 cells/mm2 (average 1,672 cells/mm2) (P < 0.01). There were no statistical significance on the transparent rate of grafts, grafts thickness, visual acurity and graft's rejective rate between fresh and cryopreserved corneas. But graft's epithelium healing was delayed and endothelium density was lower when cryopreserved corneas as donors.