EyeWorld Asia-Pacific September 2015 Issue

58 EWAP NEWS & OPINION September 2015 emulsification is enhanced by the vacuum and less ultrasound energy is needed to break up the nucleus. Bevel-down grooving also protects the corneal endothelium by projecting the ultrasound energy downward and facilitates working close to or under the iris without damaging it. One of the most important learning experiences that Dr. Pangputhipong imparts to the younger generation of surgeons is understanding nuclear disassembly techniques. There are 3 ingredients of nuclear division, he said—chop, groove, and crack—and these 3 ingredients can be combined in many ways to disassemble a nucleus. His goal has been to teach young surgeons how to understand these ingredients well enough that they can develop their own techniques as needed. As the spectrum of nuclear disassembly techniques evolved and expanded, Dr. Pangputhipong adopted the methods that worked best for him and invented several others when existing techniques fell short. He developed a 3D cracking technique that applies forces in a specific pattern, vertically and horizontally, to separate a hard nucleus with minimal force. He also developed a triangular cracking technique that can be modified for soft, medium, and hard cataracts. The technique involves making a triangular groove in the center of the cataract that is then used to split the nucleus into 3 pieces. This method minimizes the need for rotation of the fragments, adds room for manipulation, and allows for minimal hydrodissection. Around day 8,000—in 2012— Dr. Pangputhipong adopted femtosecond laser-assisted cataract surgery. But instead of abandoning the methods he had developed over the past 22 years, he simply adapted them, bringing the benefits of the old techniques to the new technology. Applying the principle of dividing a nucleus into 3 triangular pieces in his triangular cracking technique, Dr. Pangputhipong now uses the femtosecond laser to create an “X” pattern, breaking the lens into 4 triangular pieces. This method still has the benefits of minimal rotation and hydrodissection that triangular cracking had and is extremely quick, he said. For mature and hard cataracts, he uses the femtosecond laser to create the capsulotomy and then continues the case with his 3D stop and chop phaco technique. CSCRS: Escape! the Event Horizon Despite even the most experienced surgeon’s best efforts, situations can arise in which the surgeon might feel as though a gaping black hole had just opened up before them. And as with theoretical, astronomical black holes, these situations have event horizons—points of no return across which there is no recovering a case. With these situations often comes a feeling of “impending doom”—but don’t fret! Experts at the Combined Symposium of Cataract and Refractive Societies (CSCRS) have been there, done that, and are back to guide attendees through ways of avoiding crossing over the inescapable event horizons of these black hole situations. One of these situations is infusion misdirection syndrome—a topic that Chee Soon Phaik, MD, Singapore, joked was also something of a nightmare for her in terms of preparing for her lecture, owing to the paucity of published information. Infusion misdirection syndrome is the sudden, dramatic, and persistent shallowing of the anterior chamber characterized by the absence of choroidal hemorrhage or externalpressure that usually occurs during irrigation/aspiration or irrigation of the posterior capsule during cataract surgery. The pathophysiology is unclear, although Richard Mackool, MD, who coined the term, described infusion fluid accumulating in the potential space between the posterior capsule and anterior vitreous. This seems to take place despite an intact posterior capsule, but is postualted to result from anterior hyaloid membrane detachment or tear. Dr. Chee cited a prior study that identified prolonged irrigation and deflation/ inflation of the anterior chamber as a risk factor for anterior hyaloid membrane detachment, while 27-G hydrodissection is a risk factor for anterior hyaloid membrane tear—turning the potential space between the membrane and the posterior capsule into a real space. Dr. Chee has observed infusion misdirection syndrome occurring with forceful rotation of the nucleus with ineffective hydrodissection. Mild cases can be managed by watching the posterior capsule closely during irrigation/ aspiration and IOL insertion. Surgeons should also be careful when removing OVD from under the IOL. Dr. Chee manages moderate cases by running IV mannitol as quickly as is safe and waiting for the misdirected fluid to egress. Live reports - from page 57