Astigmatism is an eye disorder in which the cornea (the clear tissue covering the front of the eye) is not perfectly round. Instead of being spherical like a basketball, a cornea with astigmatism is oval shaped, somewhat like a football. This abnormal curvature can cause blurred vision. Assuming there are no other problems with the eye, this blurred vision can be improved by reducing or eliminating one’s astigmatism.
It is important to note that astigmatism present before cataract surgery typically remains after the surgery unless it is specifically addressed. A toric intraocular lens (toric IOL) is a special implant lens inserted into the eye at the time of cataract surgery. It is unique in that it not only addresses vision loss resulting from the cataract in much the same way a “standard” non-astigmatism correcting IOL does, but also addresses any coexisting astigmatism, thereby providing clearer vision without glasses. The toric IOL is therefore designed to help reduce one’s dependence on glasses after surgery.
There are several other options beside a toric IOL for reducing or eliminating astigmatism, but a toric IOL is an excellent one as it is highly predictable, safe and precise. Other methods of astigmatism correction include laser vision correction such as LASIK, limbal relaxing incisions (LRIs), or simply glasses or contact lenses. Because toric IOL’s can be placed at the time of cataract surgery, a separate procedure like LASIK is not necessary to begin to enjoy freedom from astigmatism. In addition, toric IOL’s are more predictable and can correct higher levels of astigmatism than LRIs, allowing patients to see clearly without glasses or contact lenses.