Long-term storage of frozen lenticules for cryorefractive surgery.
We studied freezing rates, cryoprotectants, and storage times on keratocyte viability, using rabbit corneal buttons incubated in either KM-26, CPTES, K-Sol, or TC 199 for 30 minutes at 4 degrees C. Using a controlled freezing rate (2 degrees/min to -40 degrees C), viabilities were 69 +/- 7% for KM-26, 113 +/- 21% for CPTES, 0.1 +/- 0.08% for K-Sol, and 0 +/- 0% for TC 199. The KM-26 and CPTES were further studied in corneas stored one to 30 days at -80 or -196 degrees C; CPTES had a better cryoprotective efficacy over one, three, and seven days of -80 degrees storage, and at liquid nitrogen storage temperature (-196 degrees) over one, 14, and 30 days storage. The findings demonstrate the superiority of CPTES. It provides better viability than KM-26 under similar conditions, and may enable long-term frozen storage of lenticules for later use in cryorefractive surgeries, with minimal loss of keratocyte viability.
Kratz-Owens
K
K
Bethesda Eye Institute, Department of Ophthalmology, St. Louis University School of Medicine, Missouri 63110.
Huff
J W
JW
Kownacki
J J
JJ
Dresner
M
M
Schanzlin
D J
DJ
D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D002809:Chondroitin Sulfates / Q000494:pharmacology; D003319:Corneal Stroma / Q000166:cytology* / Q000187:drug effects; D015925:Cryopreservation; D003451:Cryoprotective Agents / Q000494:pharmacology*; D004121:Dimethyl Sulfoxide; D005990:Glycerol; D006531:HEPES / Q000494:pharmacology; D008137:Longitudinal Studies; D011817:Rabbits; D054140:Refractive Surgical Procedures; D013997:Time Factors; D014325:Tromethamine / Q000494:pharmacology / Q000031:analogs & derivatives
D003451:Cryoprotective Agents; C051174:K-Sol preserving medium; D014325:Tromethamine; C004551:TES; C029411:1,2,3-propanetriol sulfinylbis(methane) mixture; D002809:Chondroitin Sulfates; D005990:Glycerol; D006531:HEPES; D004121:Dimethyl Sulfoxide