Fig. 3. Nomogram design. Note relative disparity in incision length between a large and small corneal diameter if measured in millimeters. Degrees of arc lend consistency irrespective of corneal size. (Reprinted from Hardten DR, Lindstrom RL, Davis EA. Phakic Intraocular Lenses: Principles and Practice. Thorofare, NJ: SLACK Incorporated, 2004, with permission.)