Eyeworld

104 April 2016 EW REFRACTIVE SURGERY by Liz Hillman EyeWorld Staff Writer "If the first procedure affects the second one, I think this is some- thing for health care planners and surgeons to discuss," Dr. Lundström said. Going forward, Dr. Lundström said further research could include repeating this study in other settings and also looking at the possible cat- aractogenesis effect of corneal refrac- tive surgery. Dr. Garg said he would like to see a study that measures lens opacity over time in post-cor- neal refractive surgery patients and non-refractive patients. He also said it would be important to figure out why the refractive patients had poorer visual outcomes after cataract surgery. "Was this related to the surgery, the IOL power calculation, the type of IOL, or [another reason]?" Dr. Garg asked. For now, Dr. Garg said the results of this study might help cataract surgeons better counsel younger post-corneal refractive surgery patients and educate them on possible visual outcomes after cataract surgery. EW References 1. Manning S, et al. Cataract surgery outcomes in corneal refractive surgery eyes: Study from the European Registry of Quality Outcomes for Cataract and Refrac- tive Surgery. J Cataract Refract Surg. 2015 Nov;41(11):2358–65. 2. Costagliola C, et al. Photorefractive keratectomy and cataract. Surv Ophthalmol. 1997 Nov;42 Suppl 1:S133–40. 3. Wachtlin J, et al. PRK and LASIK–their potential risk of cataractogenesis: lipid peroxidation changes in the aqueous humor and crystalline lens of rabbits. Cornea. 2000 Jan;19(1):75–9. 4. Mansour AM, et al. Cataractogenesis after repeat laser in situ keratomileusis. Case Rep Ophthalmol. 2012 May;3(2):262–5. Editors' note: The sources have no financial interests related to their comments. Contact information Garg: gargs@uci.edu Henderson: bahenderson@eyeboston.com Lundström: mats.lundstrom@karlskrona.mail.telia.com is about 35 years. This means that there is a delay of 15 to 20 years before they reach the age for devel- oping cataract. Over time, this group will increase." The study also revealed that the visual outcomes of cataract surgery in corneal refractive patients were generally the same as non-refractive patients. Some patients on both sides had worse postoperative cor- rected distance visual acuity (CDVA) compared to their preoperative CDVA, but refractive patients were more likely to encounter this situa- tion than the non-refractive group. Four percent of refractive patients had worse postoperative CDVA compared to 1.5% of non- refractive patients. What's more, a higher percentage of refractive patients with a preoperative logMAR CDVA of 0.0 (6/6) or better were more likely to have worse CDVA after cataract surgery compared to their non-refractive peers. This, the study authors wrote, is "worrying." Bonnie Henderson, MD, clini- cal professor, Tufts University School of Medicine, Massachusetts, who was not involved with this research, said the CDVA findings present an "important point that should be discussed [with cataract patients] during preoperative counseling to manage expectations." Although only 0.15% of the cat- aract cases in the analysis involved corneal refractive surgery patients, Dr. Lundström reiterated that this number will continue to increase, es- pecially in countries where this type of vision correction is popular. In light of that, he said cataract surgeons will face challenges in terms of intraocular lens calcula- tions and planning for the patient's postoperative refraction. "It will also mean a challenge in terms of indications for cataract surgery," Dr. Lundström said. He pointed out that in many countries, refractive surgery is not paid for by insurance and is thus paid for by the patient. Compare that to cataract surgery, which is of- ten covered by insurance or govern- ment-funded health care plans. "In general, people who seek out refractive surgery tend to expect a lot from their vison and are not tolerant of imperfections," said Dr. Garg, who was not involved with this study. "They are also willing to spend discretionary funds to improve their vision. This translates to them being less accepting of visual compromise that comes with cataracts and them seeking out care to improve their vision as soon as symptoms from cataracts begin, as opposed to controls who may not care about the slight decrease in vi- sual performance that happens early in the development of a cataract. This is reasonable given what I'm seeing in my practice." Dr. Lundström added that pre- vious studies have suggested corneal refractive surgery could be catarac- togenic. "We don't know if the previous refractive surgery triggers cataract, but as we pointed out in the article, there is some evidence that this could be the case," Dr. Lundström said. Dr. Garg said he doesn't think there is a definitive link yet between refractive surgery and cataract devel- opment. The study authors cited research published by Costagliola et al. in Survey of Ophthalmology regarding photorefractive keratectomy and cataract, 2 Wachtlin et al. in Cornea about the possible cataractogenesis of PRK and LASIK, 3 and Mansour et al. in Case Reports in Ophthalmology on "Cataractogenesis after repeat laser in situ keratomileusis." 4 Dr. Lundström said the 3-fold increase in the number of corneal re- fractive patients having cataract sur- gery during the data collection peri- od could be because the procedure is cataractogenic and/or because those who have received corneal refractive surgery are just starting to come of age for developing cataracts. "The number of patients with previous corneal refractive surgery is increasing depending on the increasing utilization of this surgi- cal procedure," he said. "The mean age for patients with myopia going through corneal refractive surgery Patients who have had corneal refractive surgery also seem to be getting cataract surgery at younger ages P atients who have had corneal refractive surgery seem to be getting cataract surgery more than a decade earlier, on average, com- pared to their non-corneal refractive surgery counterparts, according to research published in the Journal of Cataract & Refractive Surgery. 1 Using data from the European Registry of Quality Outcomes for Cataract and Refractive Surgery, Manning et al. found that of the 807,220 cataract surgeries reported in 18 European countries and Aus- tralia over a 6-year period of time, 1,029 patients had prior corneal refractive surgery. While the average age at the time of cataract surgery for these refractive patients was about 63 years old, non-refractive cases were having the procedure, on average, at 74 years old. What's more, the study au- thors reported seeing a "significant increase, over time, in the number of refractive cases" having cataract surgery. During the study period, the number of cataract surgeries in refractive patients increased from 0.06% to 0.22%. There are multiple factors that could play into these trends, accord- ing to the study authors. "As we pointed out in the article, this is a group of patients focused on their visual acuity and refraction," said Mats Lundström, MD, PhD, Department of Clinical Sciences, Lund University, Lund, Sweden, 1 of the study authors. "If their vision goes down only a little or if they become more myopic because of cataract, they request surgery very early. This is what we think is the main reason." Sumit "Sam" Garg, MD, asso- ciate professor of ophthalmology, University of California, Irvine, and medical director, Gavin Herbert Eye Institute, agreed with this assess- ment. Study reveals cataract surgery increasing in corneal refractive surgery patients

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