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Symmetrical marking of both donor and recipient corneas in penetrating keratoplasty.

The symmetrical marking of both the donor and the recipient corneas aids in the proper alignment of the donor cornea within the recipient opening. The second stitch in a penetrating keratoplasty is the most important stitch for the proper alignment of the donor cornea within the recipient opening. If the second stitch is placed too far to the right or left, there will be a gap on one side and an override on the other side. This misalignment is likely to result in a distortion of the corneal surface contour. The proper alignment can be made even more difficult if the recipient opening is distorted. The proper alignment can be facilitated by symmetrically marking both donor and recipient corneas. A simple surgical technique is described to clarify and emphasize this very important principle of penetrating keratoplasty--the alignment of the donor cornea within the recipient opening.