Astigmatic keratotomy: a review of basic concepts with case reports.

Despite the use of small incisions, better wound closure, and other technical improvements in cataract and corneal surgery, astigmatism remains a problem for the cataract and refractive surgeon. Case reports illustrate the applicability of astigmatic keratotomy in post-cataract and idiopathic astigmatism. The basic concepts of corneal relaxing incisions are reviewed and the frequently misunderstood coupling phenomenon is explained in the light of the "law of elastic domes." Properly used, astigmatic keratotomy with coupling effectively corrects a wide variety of types of astigmatism.