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By
Cheryl Guttman
“This foldable, posterior chamber, phakic IOL has many points in its favour. It can be implanted through a small incision, offers an exceptional range of correction, results in excellent uncorrected acuity, and produces vision quality that is undoubtedly superior to that achievable with corneal surgery. Furthermore, initial experience with a new toric model is very positive and suggests we can look forward to correcting astigmatism as well as spherical error with the ICL,” said Dr. Rosen, professor of ophthalmology, University of Manchester Institute of Science and Technology, UK. <“However, cataract development remains a long-term safety issue, and one has to accept that eventually all of eyes implanted with the ICL may require crystalline lens removal.> Nevertheless, patients who have had cataract surgery all enjoy excellent refractive outcomes, and overall, the ICL recipients are very enthusiastic about their vision and accompanying change in lifestyle. So, because of its high patient acceptance, I continue to perform this procedure,” he explained. He reported having implanted the ICL in 172 myopic eyes (mean sphere -9.70 D; range -8.25 to -20.75) and in 35 hyperopes (mean sphere +4.57 D; range +0.75 to +7.50). Among 105 myopes seen at 12 months, uncorrected visual acuity was 20/30 or better in 56% of eyes and 20/40 or better in 72%. The results were even better among the hyperopes, of whom 83% saw 20/30 or better uncorrected at 12 months. Predictability has been good in both myopes and hyperopes, and there have been no cases of loss of two or more lines of BCVA, while the vast majority of myopes enjoyed an increase in their best-corrected vision. “Myopes benefit with a huge gain in best corrected vision because of the magnification effect of the myopic optic, but that does not occur with hyperopic correction,” noted Dr. Rosen, adding that 40% of hyperopes lost 1 line of BCVA. Cataract Incidence in Decline Reviewing safety, he noted that cataract development continues to be the predominant issue. Among the 123 eyes with a minimum follow-up of 12 months, anterior subcapsular lens opacities developed in 24 (20%) eyes. The lens changes remained compatible with good vision and only minor glare or halos in 14 eyes, but cataract surgery was necessary in 10 (8%) eyes, he reported, adding: “I would make the points that <80% of the eyes had no lenticular problems and 92% enjoy excellent vision and are universally enthusiastic about their change in vision and lifestyle.”> Time to onset of lens opacity ranged from one month to two years. Neither gender nor type of refractive error (myopia vs. hyperopia) appeared to affect the risk. However, ICL version was an important contributing factor as it has been noted that the number of cataract cases has declined with each newer generation of the ICL, he noted. “Intermittent touch is a major factor in the development of these lens opacities, and that was a particular problem with the earlier versions of the ICL, which were much less rigid. With increasing rigidity, we see the numbers of cataracts coming down,” said Dr. Rosen. Other complications encountered included three eyes with pupil block glaucoma, including one with malignant glaucoma. All of these complications resolved with intervention, and Dr. Rosen mentioned they all occurred early in his learning curve when he was performing YAG iridotomies in eyes with thick brown irides. He now performs surgical iridectomy instead. His series also includes one decentered ICL that was successfully exchanged, one eye that developed uveitis at one month that resolved, and a single retinal detachment. Although that latter patient had a history of retinal detachment, Dr. Rosen noted myopes are at increased risk for retinal detachments and a recent paper raises the issue that posterior chamber IOL implantation may trigger retinal complications. Dr. Rosen has no financial interest in the ICL. |
Patients Like ICLs, But Cataracts Still a Concern 