EyeWorld Asia-Pacific September 2015 Issue

59 EWAP NEWS & OPINION September 2015 External pressure is reduced by loosening the speculum, through topical anesthetics and sedation (as misdirection syndrome is uncomfortable for the patient). The surgeon should then gradually deepen the anterior with retentive OVD until the posterior capsule moves posteriorly. The IOL should then be inserted carefully, and care should again be taken when removing OVD from under the IOL. In severe cases, choroidal hemorrhage needs to be excluded. Dr. Chee aspirates the trapped retrolenticular fluid through 25-G pars plana needle aspiration and performs a 23- or 25-G limited anterior vitrectomy. The syndrome can be prevented by performing gentle but adequate hydrodissection, avoiding prolonged irrigation, avoiding repeated deflation/inflation of the anterior chamber, and being on alert in high-risk eyes such as those with weak zonules. A situation that is likely more familiar to cataract surgeons is Descemet’s membrane detachment. While Descemet’s membrane detachment can occur intra- and postoperatively, Thomas Kohnen, MD , Frankfurt, Germany, said the complication can result in major postoperative sequelae, potentially causing persistent corneal edema and decreased visual acuity. Detachment can be caused by injection of OVD below the Descemet’s membrane. In these cases, treatment requires removal of the agent from the space using a blunt cannula. Intraoperative repositioning of the Descemet’s membrane can be done using BSS, air, or OVDs. Dr. Kohnen said it is also possible to perform reattachment at the slitlamp after several drops of anesthetic and antibiotics. A paracentesis incision is created inferotemporally, through which 50% of the aqueous is drained and air or an expansive gas such as sulfur hexafluoride SF6 is injected using a 27- or 30-G cannula attached to a syringe with a filter. Descemet’s membrane detachment can be prevented by careful observation of the inner lip and using a sharp metal or diamond blade during enlargement of corneal incisions. A rare complication in phacoemulsification cataract surgery—particularly with newer phaco machines—is incision “burn”—the scare quotes because, said Clara Chan, MD , Toronto, Canada, no actual tissue oxidation or burn takes place. Instead, corneal incision contracture is induced by heat generated by ultrasound friction as an acute reaction in the corneal collagen when incision temperature reaches 60°C. Incision burn sequelae include visible corneal striae, difficulty closing the incision, iris prolapse with poor wound apposition, induced irregular astigmatism, and loss of best-corrected visual acuity. In a study, Dr. Chan said that surgical volume, surgical approach, and type of OVD were most significantly associated with incision burn. She said that surgeons with higher surgical volume tended to have fewer cases of incision burn—likely because these surgeons develop techniques which minimize surgical time and therefore risk of burn. In terms of surgical approach, “divide and conquer, carousel, and stop-and-chop approaches to nucleus disassembly had an adjusted incidence of incision burn at least twice that of all other chop (vertical, horizontal) approaches (p<0.001).” In terms of OVD, Healon 5 (Abbott Medical Optics, Abbott Park, Ill.) was most significantly associated with incision burns. Healon 5, Dr. Chan said, is “highly exothermic when ultrasound is introduced through it,” while its high viscosity can block fluid flow to cool the phaco probe tip. Other “event horizons” discussed at the symposium were eccentric pupils, discussed by Graham Barrett, MD , Perth, Australia, posterior capsular rupture, discussed by Roberto Bellucci, MD , Verona, Italy, and anterior capsular tear, discussed by Tal Raviv, MD , New York. Friday, 7 August 2015 The APACRS meeting held sessions on a wide variety of topics during its full day of programming on Friday. SICS—what’s best for the patient? Almaha, a young mother widowed during the Ethiopian– Eritrean War, developed cataracts from injuries and subsequently came under the care of Sanduk Ruit, MD , Kathmandu, Nepal. His video of the case at yesterday’s symposium on “Cataract Conundrums” elicited an audible gasp from the audience: contrary to convention, Dr. Ruit implanted the IOL at the beginning of the procedure, rather than the end. Dr. Ruit explained the decision: lacking more sophisticated instrumentation, he said, he used the lens to stabilize the capsular-zonular diaphragm before bringing the nucleus out. He was making a very particular point: In considering her particular case, Dr. Ruit thought not about what technique was good for the cataract, but what was good for the patient. Cataract surgery, he said, is a matter of thinking about and doing what is best for the patient. He was aiming to perform the surgery in a way that would continued on page 60