Refractive Lens Exchange
Refractive Lens Exchange (RLE), also known as Clear Lens Exchange (CLE), is a surgical procedure to correct refractive errors in which the natural lens of the eye is removed and replaced with artificial intraocular lens. This surgical procedure is very similar to cataract surgery, however in cataract surgery the lens is clouded, whereas in this surgery, the clear lens is removed.
In refractive errors such as hyperopia (farsightedness) or myopia (nearsightedness) the light entering the eye does not get focused properly on retina because of the lens which is either too weak or too strong to help focus light properly. Refractive lens exchange procedure corrects the error and focuses the light on the retina by removing the natural lens in the eye and replacing it with a new artificial lens, thus reducing or eliminating the need for additional glasses or contact lens.
Refractive lens exchange is used for correction of severe farsightedness, nearsightedness, presbyopia (diminished ability to focus on near objects), and astigmatism (blurred vision) that is not easily managed by other refractive procedures. People with these refractive errors may have mild cataract that eventually could worsen and cloud the eye’s natural lens. In such cases a refractive lens exchange may help instead of waiting for the cataracts to advance enough to require cataract surgery. A multifocal or monofocal lens implants may be used for replacing the natural lens in these patients.
The most likely candidates for RLE surgery are those aged 21 years or more, who are not satisfied with eyeglasses or contact lenses and those who had no change in their prescription eye glasses or contact lens for at least a year.
Before the surgery, tests such as visual acuity, slit lamp examination, and dilated examination are performed. In visual acuity test you will be asked to read the smallest letters that you can see on the standardized chart (Snellen chart) held 14 – 20 inches away from you. The slit lamp examination uses a special microscope (slit lamp) that provides a detailed view of the different parts of the eye. During the exam, your doctor can look at the front parts of the eye including the clear outer covering (cornea), the lens, and the colored part (iris). Special lenses are used with the slit lamp to view deeper structures of the eye, such as the retina and the optic nerve. Dilated examination is a procedure in which a special eye drops is used to dilate or enlarge the pupil to allow your doctor a good view of the back of your eye.
If you are a candidate for RLE, your surgeon will suggest you to stop wearing lens for few weeks before the surgery because the contact lenses cause mild distortion in the shape of the cornea.
The RLE procedure usually takes about 20 minutes and is performed under a local anaesthesia. Once the eye is numbed, a tiny incision is made in the periphery of the cornea. Your surgeon uses an ultrasound probe to break up the lens which is then removed by suction. This process is called phacoemulsification. Then the plastic lens is introduced in the same lens capsule as the natural lens. The incision heals on its own and does not require any sutures. Your doctor may place antibiotic eye drops and a patch over the eye. After the surgery you may experience mild burning and irritation in eyes.
Following surgery your doctor will prescribe eye drops to prevent infection and inflammation. You need to clean gently the area around the eye using a damp wash cloth. Rubbing or pressing on the eye, swimming, using soaps or dirty water in the eye, hot tubs, lifting heavy objects, and bending at the waist should be avoided for few weeks. A follow up visit is scheduled to monitor healing and to check for vision.
The possible complications associated with RLE are infection, swelling of the eye structures, detached retina, and increase in intraocular pressure. In some cases posterior capsule opacification, a hazy membrane (capsule) just behind an intraocular lens implant may develop after several months following RLE surgery. This may cause blurred vision or glare symptoms. This can be corrected by your surgeon by a procedure known as YAG capsulotomy.