Eyeworld

49 EW FEATURE December 2016 • Highlights from ESCRS 2016 prevent blockage. We modified the lens to have fenestrations, which would allow the surgeon better manipulation to bring the optic into the capsular remnant, and allow egress of fluid from the capsule bag, precluding capsule block," he ex- plained. None of the eyes implanted with the original or modified 90S IOL developed ND, proving that having the optic anterior to the cap- sule will eliminate ND, Dr. Masket said. "While ND continues to plague some of our patients, we think we have a better understanding of the mechanisms and the prevention of it," he said. In addition to preventing ND, there are a number of advantages that accrue when the IOL is fixated by the anterior capsulotomy as in the case of the BIL and Morcher 90S IOL. The capsulotomy supported IOL has very stable fixation, and the same IOL may be used with an open posterior capsule, such as with posterior capsule tears. There can be no capsule contraction and decentration because the capsule is captured in the rigid lens. There will be no tilting of the IOL optic and, toric IOLs will not shift axis. More- over, there can be perfect centration and more predictable ELP. "If one can center the capsulotomy on the visual axis, one can also eliminate higher order aberrations induced by the lens," Dr. Masket said. EW References 1. Schaumberg DA, et al. A systemat- ic overview of the incidence of posterior capsule opacification. Ophthalmology. 1998;105:1213–21. 2. Verbruggen KH, et al. Intraocular lens centration and visual outcomes after bag-in- the-lens implantation. J Cataract Refract Surg. 2007;33:1267–1272. 3. Tassignon MJ, et al. Clinical results after spherotoric intraocular lens implantation using the bag-in-the-lens technique. J Cataract Refract Surg. 2011;37:830–4. 4. Masket S, et al. Pseudophakic negative dysphotopsia: Surgical management and new theory of etiology. J Cataract Refract Surg. 2011;37:1199–1207. Editors' note: Drs. Masket and Tassignon have financial interests with Morcher. Contact information Masket: sammasket@aol.com Tassignon: Marie-Jose.Tassignon@uza.be study, the geometric center of the IOL, as measured by red reflex slit lamp photography, was compared with the geometric center of the pupil and the limbus. It concluded that capsular bag healing had no influence on BIL IOL centration over time. 2 "The pupil is not necessarily in the middle of the mathematical cen- ter of the limbus. For instance, the more myopic the patient, the more the pupil will be decentered nasally. That means that to center the IOL properly, you would need to use the pupil. However, you cannot change the position of the IOL according to the pupil when implanting tradi- tionally. Traditional implantation is based on the capsule, and because it is not centered behind the pupil, IOLs will end up decentered. This may not be a big problem when im- planting monofocal lenses, but it is a problem when dealing with complex lenses like toric or multifocal IOLs. However, using BIL, the surgeon can choose where to center the lens," she said. She noted that although BIL implantation allowed a certain flexi- bility of IOL placement, the options were not limitless as the capsule needed to maintain its structural integrity. Nonetheless, in a series of toric IOL implantations that based IOL centration on patients' pupil- lary entrance using Purkinje reflexes of the surgical microscope light, Dr. Tassignon demonstrated 82% astigmatism correction in 52 eyes of 35 patients using spherotoric BIL IOL implantation. 3 "When you put a toric element in your lens, you are correcting a corneal problem on the lenticular plane, at the distance of approximately 4 mm from where the problem is occurring. You have to take a good look at the problem and at the architecture of the cor- nea. This may not always be possible using traditional IOL implantation," she said. Keep it simple According to Dr. Tassignon, ophthal- mic surgeons do not always need to use sophisticated methods and machinery to produce a perfectly sized and centered anterior capsu- lorhexis with accurate, reproducible results. She recommended the use of a ring caliper for reliable rhexis sizing and centration, at low cost. She explained, "I am a big advocate of trying to avoid the booby trap of paying excessive amounts of money to use difficult and complex devices, like the femtosecond laser, that may play a role in imprecise corneal mea- surements. In the end, the comfort of pressing a button cannot replace the excellent results achieved with more simple techniques. We have to think about cost and use machinery thoughtfully. I try to apply all the knowledge I have accumulated over 33 years of experience, and I find that simple devices and techniques allow a perfect, well-centered IOL implantation." Dr. Tassignon is expecting the first prototype of a diffractive version of the BIL IOL, which is the first IOL to incorporate diffractive elements onto the posterior side of a lens where the posterior capsule cannot play a role in reducing the diffractive pattern since it is not present. Negative dysphotopsia It seems that the concept of captur- ing the lens with the anterior cap- sule can be of benefit against other in-the-bag traditional cataract surgi- cal complications. According to ob- servations from recent case studies, the updated anti-dysphotopic 90S IOL (Morcher) could eliminate the occurrence of negative dysphotopsia (ND), a temporal dark crescent re- ported by cataract patients following uncomplicated cataract surgery. "The evidence seems to suggest that the final common pathway for ND is any 'in-the-bag' IOL with the anterior capsulotomy edge overlying the optic," Dr. Masket said during his presentation at the ESCRS meet- ing. "Therapy or prevention of ND involves placing the lens anterior to the capsule or a portion of the lens anterior to the capsule, which can be accomplished using a method referred to as reverse optic capture." In a presentation of 55 eyes requiring management or preven- tion of ND, Dr. Masket reported that reverse optic capture (ROC) was successful in 19 of 20 eyes that expe- rienced ND for more than 6 months following cataract surgery. Moreover, 20 of 20 fellow eyes of symptomatic patients had primary ROC, which successfully prevented ND. Other strategies for managing ND included exchange of the IOL from bag to sulcus, which relieved ND in six of seven eyes. Bag to bag exchang- es, however, for a lens of different design or material failed to help in all four cases. Piggyback lenses were successful in eight of 11 eyes. These last results mirrored outcomes from a previous trial conducted by Dr. Masket in which he found that pig- gyback IOLs and ROC were the most successful approaches to eliminating ND in a retrospective case series of 14 patients/12 eyes experiencing ND after uncomplicated cataract surgery with in-the-bag IOL implantation. 4 Dr. Masket said that negative consequences with primary ROC were noted in second eye implanta- tions, i.e., non-symptomatic fellow eyes, as early post-surgical fibrotic PCO necessitated capsulotomy. Also, the long-term sulcus placement of an add-on lens was thought to be associated with decentration and iris chafe. The Morcher 90S IOL was de- signed by Dr. Masket in part to simu- late ROC in order to prevent ND. At this time, approximately 60 of the IOLs have been implanted in limited clinical trials. The 90S IOL has an equatorial groove designed to cap- ture the anterior capsulotomy. The IOL design allows a small segment of the optic to overlie the capsule and the haptics to be placed inside the capsule bag, Dr. Masket explained. The first 39 eyes received an initial version of the 90S IOL. Of these patients, femtosecond laser was used to create the anterior capsulotomy in 29 of 39 eyes, which measured 4.8 to 4.9 mm in size. Capsule block was experienced in three of 29 eyes, from fluids trapped behind the capsulotomy. In two eyes, the IOL failed to capture the anterior cap- sule. There was no case of ND (0/39) or iris chafe (0/39) in this series. The anterior capsulotomy must be appropriately sized and placed; an automated or guided capsulotomy is the best approach. Going back to the drawing board, Dr. Masket edited the lens design to include fenestrations that could allow the passage of fluids and prevent capsule block. "The challenge at this point was to design a lens that could handle all these issues, still fill the capsule bag, have a portion of the optic anterior to the capsulotomy, and allow fluids to pass through the capsulotomy and

• Cover