Clear Lens Extraction
For individuals over 40 who are considering refractive surgery to decrease dependence on glasses and contact lenses, clear lens extraction (CLE) is an exciting option. In essence, this procedure entails removing the
natural lens of the eye and replacing it with an intraocular lens (IOL) implant. The procedure is essentially the same as a cataract operation with lens implant, however, in this case, the procedure is completed prior to cataract development for the refractive advantage. With the benefit of powerful ultrasonic instrumentation to measure the length of the eye to within 100ths of a millimeter, and sophisticated IOL formulas, ophthalmologists have become very accurate at determining the proper IOL power to decrease post-operative dependence on eyewear.
CLE is a procedure that is more invasive than LASIK or PRK with consequent greater risks. However, CLE may be an excellent alternative to these procedures for people already wearing bifocals or for those who do not qualify for other refractive procedures due to extremes of refractive error. Because CLE requires entering the eye to place the lens implant, the patient has a small risk of infection inside the eye that is not present in LASIK or PRK. Unlike these procedures, however, CLE avoids any treatment of the cornea and instead changes the refractive power of the eye in a potentially more natural position.
Because CLE requires removal of the natural lens of the eye, the patient is subsequently unable to focus at near (accommodate). This is why CLE is best suited for patients over 45 who are already wearing bifocals. One potential solution to this problem of accommodative loss is implantation of a multifocal IOL implant. This implant allows focusing at both near and far, allowing patients to read small size print and drive a car without glasses, following implantation of the lens in both eyes.
A second alternative for patients who are considering CLE but who do not embrace the notion of wearing reading glasses following surgery, is monovision. With monovision, the traditional monofocal IOL implant is inserted bilaterally, however, the patient’s dominant eye is corrected for distance and the non-dominant eye is corrected for near. This option is not tolerated by everyone. To determine whether this is a good option for you, Edina Eye Physicians offers a monovision contact lens trial. Patients tolerating monovision will likely tolerate this CLE option.