tial for posterior dislocation of the donor corneal disc in aphakic eyes must be taken into consideration. Longer-lasting, higher-buoyancy gases (such as SF6) could be used as alternatives to air, but the possible toxic effect to endothelial cells should be elucidated. Correspondence: Dr Yoo, Cornea and External Diseases, Bascom Palmer Eye Institute, 900 NW 17th St, Miami, FL 33136 (syoo@med .m...
