EyeWorld Asia-Pacific December 2012 Issue

19 December 2012 EWAP FEATURE Highspeed Scheimpflug Imaging – the Future of Diagnostics OCULUS Asia Ltd. Hong Kong Tel. +852 2987 1050 • Fax +852 2987 1090 www.oculus.de • info@oculus.hk OCULUS Corvis ® ST Highspeed Scheimpflug camera in combination with non-contact tonometer: • Precise measurement of IOP • Precise measurement of CCT • Potential to measure biomechanical properties • Screening for corneal ectasia “If you put a monofocal lens in, their quality of vision is much better,” he said. Timing an explantation Popular discourse dictates that a lens should be removed sooner than later. “Do it as soon as you have an idea that it needs to be done,” Dr. Safran said. “If you know very early on that an exchange will be needed, it’s easier to do it before there has been a lot of fibrosis.” Trying to take a lens out after a YAG capsulotomy complicates an exchange, Dr. McCabe said. “It is important to perform the exchange before opening the capsular bag with the YAG laser to minimize the risk of vitreous prolapse through the capsulotomy and subsequent need for anterior vitrectomy with increased risk of CME,” she said. Dr. Tipperman takes issue with what he calls “the myth of 12 weeks.” “People will say that the lens has to be taken out within 12 weeks—if you don’t take it out within 12 weeks, you can’t do it. That’s absolutely not true,” Dr. Tipperman said. “Twelve weeks is a very artificial myth that people quote all the time like gospel, and it affects their clinical management of these cases.” Both YAG capsulotomies and shrunken anterior capsulorhexis present challenges, but these can be overcome. “If the rhexis is large, I’ve exchanged people more than 2 or 3 years out from cataract surgery,” Dr. Tipperman said. He said that many surgeons believe that a lens can’t be exchanged once the patient has been YAGed. “I’ve exchanged a lot of people over open capsules,” Dr. Tipperman said. “It’s much harder to do the implant exchange if the patient has been YAGed, and the risks are greater, but there is no question you can do it.” Pearls for exchange When it comes to exchanging a multifocal lens, Dr. Tipperman said it’s important to remember “dispersive viscoelastic is your friend.” Drs. McCabe and Safran agreed. “You don’t want to cheapen out on a lot of viscoelastic and end up needing to do a vitrectomy,” Dr. Safran said. “I often go through two sets, which is four tubes.” Dr. McCabe keeps a backup three-piece lens for possible sulcus or iris fixation, a set of micro- instruments from MST (Redmond, Wash.), and 9-0 double-armed prolene sutures on hand. After the capsular bag is inflated, a surgeon may have to separate the anterior capsular edge and the anterior lens surface with a 27-gauge needle that is slipped under the capsular edge, Dr. McCabe said. Hydrophilic lenses have haptics that often have bulbous ends that can get caught up in fibrotic tissue. “If the haptic is so firmly enmeshed that damage may occur to the zonules when trying to extract, the haptic can be cut and left behind without ill effects,” Dr. McCabe said. Dr. Tipperman said many surgeons worry about cutting the capsule when they are using scissors to cut the lens. “I bring the lens into the anterior and then take the new lens and put it in the capsular bag before I take the old lens out, and then I cut the old lens in half,” he said. “The new lens is already in the capsule protecting everything before I take the old lens out.” Dr. Safran, on the other hand, likes to completely remove the old lens before implanting the new one. “I like to get that first implant out and see what’s going on with the capsule, and then I like to dissect away fibrosis and strip it off the anterior and posterior capsule as much as possible using the microforceps,” he said. EWAP Editors’ note: Drs. McCabe and Safran had no financial interests related to this article. Dr. Tipperman has financial interests with Alcon (Fort Worth, Texas, USA/Hünenberg, Switzerland). Contact information McCabe: cmccabe@theeyeassociates.com Safran: safran12@comcast.net Tipperman: rtipperman@mindspring.com