Current Opinion in Ophthalmology, v 13, 1 (February 2002).
"Clear Lens Extraction with Intraocular Lens Implantation for the Correction of Refractive Error"
Robert M. Kershner, M.D., F.A.C.S.
Director, Eye Laser Center
Clinical Professor of Ophthalmology, University of Utah School of Medicine, Moran Eye Center, Salt Lake City, Utah
Ik Ho Visiting Professor of Ophthalmology, Chinese University of Hong Kong, Hong Kong, SAR, China
Eye Laser Center
1925 West Orange Grove Road
Tucson, Arizona USA 85704-1152
Phone: (520) 797-2020 Fax: (520) 797-2235
Lens extraction with the implantation of an intraocular lens is the most commonly performed refractive procedure in the world today. Since the invention of the intraocular lens by the late Mr. Harold Ridley of England in 1949, lens implantation has been the primary correction of the most common refractive error, that occurs as a result of cataract extraction, aphakia,. In 1995, I published my results on the technique of clear corneal cataract surgery with the simultaneous correction of myopia, hyperopia and astigmatism (1). Today, cataract surgery is looked upon more often as a refractive procedure that is used to treat a clouded crystalline lens and simultaneously improve preexisting refractive error to optimize uncorrected visual acuity.
The increasing acceptance of refractive procedures to eliminate or reduce the need for spectacle and contact lens correction for ametropias first gained acceptance with the radial keratotomy technique of the late S. N. Fyodorov of Moscow, Russia. Then in the early 1990s, the development of the excimer laser, enabled surgeons to correct a larger array of refractive errors. Utilized in combination with the automated keratome to create a corneal flap under which is removed by the laser a small layer of cornea, LASIK as it is called (laser-in-situ-keratomilleusis), has gained in popularity over the past decade. The difficulty of using a mechanical device to create a consistent corneal flap, and the limitations of removing corneal tissue without compromising the corneal integrity, has lead surgeons to embrace an intraocular approach to the correction of high orders of refractive error. Much work has been undertaken on the use of refractive implantable lenses either in the anterior chamber, iris supported or in the posterior chamber to solve refractive problems with an implantable device. This approach also has held promise for the correction of presbyopia, the natural loss of accommodative ability that comes with age.
The application of laser technology or implantable lenses has fallen short of expectations for that population of individuals who have high degrees of refractive error. In addition, individuals who have corneal abnormalities such as, irregularity, keratoconus, corneal dystrophies or scars, may be ineligible for corneal surgery. What do we offer those in whom corneal alteration procedures cannot be pursued? For these individuals and for those for whom the visual quality of an intraocular lens implant with the simultaneous correction of refractive error, may prove superior, the choice of lens surgery may be a more acceptable alternative.