Raymond Stein, MD, has extensive experience helping patients throughout North America with their vision correction. In the article below, Dr. Raymond Stein discusses the benefits of Implantable Contact Lenses.
Phakic implants are used in vision correction for high refractive errors that cannot be treated with laser eye surgery. Over the past 12 years I have been inserting the Implantable Contact Lens (ICL), a posterior chamber phakic implant made by Starr Surgical. Clinical outcomes for high myopia and astigmatism have generally been excellent with 95 percent of patients achieving 20/30 vision or better.
The main indications for ICL candidacy are refractive errors that are too high for laser vision correction. In general patients are candidates for a phakic implant if they have myopia (nearsightedness) greater than 10 D or hyperopia (farsightedness) greater than 5 D. Astigmatism can be treated up to 6 D. Patients must have a satisfactory depth of the anterior chamber (distance between the corneal endothelium and the crystalline lens) of greater or equal to 2.8 mm. In general, most patients with high myopia are eligible for this type of treatment, unlike individuals with high hyperopia. In addition, ICL candidates should also have a pupil size of 7 mm or less.
Another surgical option, which patients need to know about, is the refractive lens exchange (RLE) procedure. My preference is not to perform a lens exchange for patients suffering from high myopia because of the increased risk of retinal tears and detachment. This is not the case with the treatment of high hyperopia, which is associated with a minimal retinal risk. This is why patients who suffer from extreme farsightedness and are not good candidates for ICL, often undergo refractive lens exchange.
Patients who are good candidates for the ICL, a refraction is performed, the limbal white-to-white distance is measured to determine the length of the implant, and two small YAG laser iridotomies are administered to reduce the risk of elevated intraocular pressure from papillary block. The implant is custom ordered from Switzerland.
The surgical procedure is relatively easy for most patients. At the Bochner Eye Institute we perform this procedure in our sterile operating room approved by the Ontario College of Physicians and Surgeons. During the procedure, which is performed under topical anesthesia, a 2.8 mm limbal incision is constructed. Next, an Intraocular xylcaine is injected to numb the eye. After carefully folding the implant into a cartridge, it is injected into the anterior chamber where it gradually unfolds. Using a specialized instrument the haptics are gently placed behind the iris. Miochol is then injected to constrict the pupil and Intraocular Vancomycin to prevent infection. Following this fairly simple procedure, patients remain at the surgical suite for about an hour during which time they are closely monitored, which allows us to ensure that the intraocular pressure is normal. Follow-up visits are generally necessary in intervals of one day, one week, one month and three months.
Complications following an ICL procedure are rare. There is, however, a 1 percent chance of inducing a cataract. Also, patients who are not satisfied with the level of uncorrected vision are eligible to undergo laser vision correction. I have not had a case of infection over the past 12 years.
Specialized indications for the ICL include patients with keratoconus and those following radial keratotomy. Keratoconus patients who have satisfactory best-corrected spectacle acuity (20/40 or better) may want to consider ICL. Some patients may require an Intracorneal ring to reduce the degree of irregular astigmatism prior to a phakic implant. In addition, the hyperopic shift, which may develop in patients following radial keratotomy, can be corrected during the ICL procedure. This is because the post-RK eyes that were previously myopic usually have a satisfactory anterior chamber depth.
To learn more about Raymond Stein and how the team at Bochner Eye Institute can help you, please visit www.bochner.com or call 416-960-2020.