Hydration changes in cadaver eyes prepared for practice and experimental surgery.
OBJECTIVE
To identify reliable and efficient methods of thinning postmortem corneas for surgical experiments and to develop methods of maintaining stable corneal thickness.


METHODS
Three methods of corneal thinning were evaluated by group: group A, increased intraocular pressure; group B, exchange of anterior chamber fluid with dextran solution and immersion in dextran solution; and group C, immersion in dextran solution without aqueous replacement. The stability of the thinned central cornea was then evaluated by exposing 30 corneas thinned by methods used in groups B and C to air, Balanced Salt Solution drops (Alcon, Fort Worth, Tex), or dextran solution drops.


RESULTS
By 1 hour, the thinning method used in group A resulted in only three of 11 eyes achieving normal central corneal thickness. The method used in group B resulted in normal central thickness in 14 of 14 corneas and in group C, in nine of 15 corneas, at 1 hour. Once thinned by methods used in group B or C, air exposure further thinned the 30 additional corneas by 22% to 26%, Balanced Salt Solution drops thickened the corneas by 16% to 22%, and dextran solution drops stabilized the corneas with only 5% to 13% additional thinning.


CONCLUSIONS
Hyperosmolar solutions were more efficient than pressure gradients in thinning the cadaver central cornea. Hydration shifts of the de-epithelialized cornea were dramatic with use of Balanced Salt Solution drops or drying and were minimized with use of hyperosmolar topical solutions.
Terry
M A
MA
Devers Eye Institute, Good Samaritan Hospital and Medical Center, Portland.
Ousley
P J
PJ
Zjhra
M L
ML
D000368:Aged; D000867:Anterior Chamber / Q000378:metabolism; D001834:Body Water / Q000378:metabolism*; D002102:Cadaver; D003315:Cornea / Q000378:metabolism* / Q000601:surgery*; D003911:Dextrans / Q000378:metabolism; D006801:Humans; D007429:Intraocular Pressure; D009798:Ocular Hypertension / Q000503:physiopathology; D009926:Organ Preservation; D054140:Refractive Surgical Procedures
D003911:Dextrans