Relaxing Incisions For
Correction of Astigmatism

The usual shape of the front surface of the eye (the cornea) is round. It allows focused light to converge at the back of the eye, on the retina. If the corneal surface is oval instead of round, a condition known as astigmatism is present.  Astigmatism causes blurred vision and is corrected with either glasses or contact lenses, and in some cases, surgery.

Surgically placed relaxing incisions, small incisions on the edge of the corneal surface, cause the corneal curvature to change, becoming more rounded, thereby reducing astigmatism. The incisions differ in number and length according to preoperative measurements.

Relaxing incisions do not always totally eliminate astigmatism. In some cases, there may be "over-response" or "under-response." Seldom is corneal astigmatism completely corrected; however, significant reduction produces a more normal visual result.

When performed in combination with cataract and lens implant surgery, relaxing incisions can result in improved uncorrected visual acuity which in turn decreases the need for glasses after surgery.