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EW CATARACT/IOL 28 May 2011 by Enette Ngoei EyeWorld Contributing Editor Cracking hard cataracts in the developing world parable in the two groups (PZ.805), and the manual SICS group had less corneal edema (10.2%) than the phacoemulsification group (18.7%) (PZ.047). The results showed similar un- corrected visual outcomes between the two groups at 6 weeks, Dr. Venkatesh said. Although the phaco group had an edge over the manual SICS group because the incision was smaller, the SICS group also did well, he said. UDVA was 20/60 or better in 99 patients (87.6%) in the phacoemul- sification group and 96 patients (82.0%) in the manual SICS group (PZ.10), and the corrected distance visual acuity (CDVA) was 20/60 or better in 112 (99.0%) and 115 (98.2%), respectively (PZ.59), the study authors wrote. In addition, the average time it took for surgery was statistically sig- nificantly shorter in the manual SICS group (8.8 minutes+/–3.4 [SD]) than in the phacoemulsification group (12.2+/–4.6 minutes) (P<.001), the study authors noted. In terms of complications, posterior capsule rup- ture occurred in three eyes (2.2%) in the phacoemulsification group and two eyes (1.4%) in the manual SICS group (PZ.681), the study said. The researchers concluded that both techniques achieved excellent visual outcomes with low complication rates. Mark Packer, M.D., clinical as- sociate professor of ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, said it is remarkable how good the results from SICS in these very difficult cases were. "The results are comparable to phaco in this group a third of the time. The procedure is significantly quicker and the complication rate is the same. Depending on where you draw the line in terms of results, their uncorrected visual acuity is about the same at 6 weeks," he said. In this case, the researchers drew the line at 20/60, Dr. Packer said, which is a relevant line for peo- ple in the developing world. When encountering a cataract like these mature white brunescent cataracts, Dr. Packer said he thinks about doing an extracapsular cataract extraction because the amount of phaco ultrasound energy needed would toast the corneal en- dothelium, and he would end up having to deal with corneal edema. On the other hand, opening the eye to the size of an extracapsular inci- sion increases the risk of an expul- sive choroidal hemorrhage or certainly astigmatism, he said. Dr. Packer said that in this study, while the surgically induced astigmatism was higher in the man- ual SICS group, it wasn't off the charts. Dr. Venkatesh said that he and his colleagues strongly feel that in advanced cataract cases, it is better to perform small-incision surgery than phacoemulsification as it is more cost efficient, has fewer com- plications, and when compared with phacoemulsification, offers equal if not better uncorrected visual acuity at the end of 1 month when the wound heals completely. Small-incision surgery is the most popular technique, whether it is a white cataract or a normal cataract, in the developing world be- cause of the lack of availability of phaco machines, the training needed to perform phaco, and the cost related to daily consumables such as tubing, phaco tips, and fold- able IOLs, Dr. Venkatesh said. For most surgeons in the devel- oping world, especially in India, the rest of Asia and Africa, small-inci- sion surgery is the predominant pro- cedure. Dr. Packer said that for surgeons who are considering learning this, there are organizations like the Himalayan Cataract Project that wel- come people to come and volunteer for a period of time and learn it for themselves. "I think it's fascinating to see this in action. There are incredibly fast surgeons, and they make it look like a whole different operation than what we're used to," Dr. Packer said. EW Editors' note: Drs. Packer and Venkatesh have no financial interests related to their comments in this article. Contact information Packer: 541-687-2110, mpacker@finemd.com Venkatesh: venkatesh@pondy.aravind.org W hite cataracts are very common in the devel- oping world, accord- ing to Rengaraj Venkatesh, M.D., Aravind Eye Hospital, Pondicherry, India. Unfortunately, in such cases, while it's still possible to do pha- coemulsification—the most ad- vanced technique available—there are many related complications, es- pecially among patients of surgeons who are less skilled in the procedure, he said. "Because manual SICS [small-in- cision cataract surgery] is signifi- cantly faster, less expensive, and less technology-dependent than pha- coemulsification, it may be a more appropriate technique in eyes with mature cataract in the developing world," Dr. Venkatesh said. Therefore, Dr. Venkatesh and his colleagues conducted a randomized, prospective study to compare the safety and efficacy of phacoemulsifi- cation and manual SICS to treat white cataracts in southern India. The researchers randomly assigned consecutive patients with white cataracts to have phacoemulsifica- tion or manual SICS by one of three surgeons experienced in both tech- niques. They compared surgical complications, operative time, un- corrected (UDVA) and corrected (CDVA) distance visual acuities, and surgically induced astigmatism. The researchers reported that 1 day post-op, the uncorrected dis- tance visual acuity (UDVA) was com- ber or migrate to the inferior angle, Dr. Mifflin added. It's possible that in this case the fragment could have been lodged behind the iris initially, then it moved to the anterior segment, Dr. Mifflin reported, noting there is some precedent for such a move. "Another theory presumes nu- clear fragments contain antigens that cross-react with antigens on en- dothelial cells, causing an immune response directed at the endothe- lium," Dr. Mifflin reported. "Thus, another possible explanation for the late-onset corneal edema in our pa- tient is that the retained lens frag- ment might have settled in a loca- tion away from the endothelium and not caused direct trauma but rather a smoldering immune re- sponse to the endothelium. After 2 years, the endothelium decompen- sated and corneal edema ensued." Dr. Mifflin urged surgeons to use gonioscopy in patients with corneal edema post-cataract surgery to search for retained fragments, even if phacoemulsification was per- formed years previously. John D. Sheppard, M.D., pro- fessor of ophthalmology, microbiol- ogy, and immunology, Eastern Vir- ginia Medical School, Norfolk, said it's not unusual to find retained nu- clear segments long after cataract surgery. "With post-cataract trans- plants we're always finding leftover lens material," Dr. Sheppard said. "Usually it's cortical but sometimes there are small fragments of nucleus. This tells us that perhaps low-grade inflammation contributed to the de- mise of the endothelium, requiring the transplant." Fragments are hard to find with DSAEK surgery because of the small scleral tunnel employed. "With an open-sky transplant, it's easier to probe every nook," Dr. Sheppard said. "Many times we find fragments embedded in the angle that are reasonably well tolerated, judging by our first impressions." EW Editors' note: Dr. Mifflin has no finan- cial interests related to this study. Dr. Sheppard has no financial interests re- lated to his comments. Contact information Mifflin: mark.mifflin@hsc.utah.edu Sheppard: 757-622-2200, docshep@ hotmail.com Physicians continued from page 27

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