Suture patterns and corneal graft rotation in the cadaver eye.

Torque and antitorque running sutures as described by Eisner are commonly used in penetrating keratoplasty. We tested the rotational effect of three different 16-bite running suture patterns on eight cadaver eyes, with the following results: (1) the torque pattern rotates the corneal graft counterclockwise by 0.7 +/- 0.1 mm at the wound or 11 degrees; (2) the antitorque pattern rotates the corneal graft clockwise by 0.7 +/- 0.1 mm at the wound or 11 degrees; (3) an intermediate "no torque" pattern, the bites of which form an isosceles triangle, produces no rotational effect. We recommend the use of a "no torque" pattern to minimize corneal graft rotation.