FEATURE 8 EWAP MARCH 2022 Dr. Fram said Robert Osher, MD, reported that the percentage of patients with negative dysphotopsia on postop day 1 is approximately 15%.2 The working theory of negative dysphotopsia based on ray tracing is that some light rays are bent by the lens and some are missed,3 which creates an illumination gap on the nasal retina causing a dark shadow temporally. In talking to patients before surgery, Dr. Fram said that she mentions that this is something that can occur, particularly in patients needing a high power IOL or who have a large angle kappa. However, she doesn’t mention the word “dysphotopsia.” Instead, she explains that the intraocular lenses used have the potential to cause glare or shadowing, and if this is a problem, she can help. Dr. Fram said it’s important to ask if this issue is always there or it comes and goes. “If it’s not always there or only there in certain lighting, I’m optimistic that the patient will adapt and not require an intervention,” she said. Dr. Osher’s research found that 97% of cases resolved within a year.2 That’s very encouraging to the patient, she said. Randall Olson, MD, agreed that this is an issue that’s often seen in the first couple of weeks after surgery, though he also sees a lot of patients who have been referred to him with a persistent problem. For the majority of patients, it’s not a big issue. However, Dr. Olson stressed that it’s important not to tell patients that you don’t know what it is or that it’s a rare complication. “I let them know ahead of time that these IOLs are smaller than our own lens, things can happen, but these things are normal,” he said. “Most of the patients I see, by the time they get to me, have been told they should be happy with their vision, and it’s an uncommon complication,” he said. “The angriest are those who have been led to think they’re crazy.” Dr. Olson said he tells patients that this is something that will go away on its own. The hard part with negative dysphotopsia, Dr. Fram said, is explaining to patients that it’s unknown whether or not it will happen in the other eye. Some patients are cautious about moving on to the other eye, and that’s where you get into a predicament, she said. “If you have a big difference between the eyes or anisometropia, you want to move on to the other eye.” There are a couple of ways to approach this. The physician could say, “We don’t know the true incidence, but there’s about a 50% chance that this could happen in the other eye,” Dr. Fram said. Assure the patient that if this happens, you can help them. You can wait a month to see if it starts to get better or choose a different strategy for the other eye, which is to put the lens in a different position. This involves doing a primary reverse optic capture (ROC) so that the optic is on top of the capsule with the haptics in the capsule bag oriented vertically. This is best performed with a 3-piece IOL. “We prefer the L161AO SofPort IOL B and L [Bausch + Lomb] as silicone has a lower index of refraction than acrylic and is more friendly in the sulcus,” Dr. Fram said. A singlepiece acrylic in the primary ROC position can lead to capsule block and is not ideal for this procedure, she said. Samuel Masket, MD, et al.4 reported on this and found that 100% of patients did not have negative dysphotopsia in the second eye when this strategy was used. That is for the patients who really can’t wait and are bothered by the first eye but need to move on to the other eye because they’re not functional, Dr. Fram said. But for many patients, she’s able to wait and see if the issue resolves over time. In her experience, typically by 3 months, the patient has improved. For patients in whom the negative dysphotopsia has persisted for 6 months or longer, Dr. Fram said you may need to move on to other options. The treatment strategy is to move the optic forward and thus move the illumination gap outside of the nasal retina. The nasal capsule has also been implicated in the multifactorial etiology of negative dysphotopsia, and covering the nasal capsule with the optic has improved symptoms. Strategies for treatment in persistent negative dysphotopsia include ROC, sulcus IOL, piggyback IOL, and nasal capsulectomy. She said secondary ROC works best if the patient’s capsulotomy is 4.5–5 mm and if they have an AcrySof IOL (Alcon) with the haptics oriented vertically.4, 5 It is less predictable with other platforms as they are more rigid and may slip back into the bag, she said. If ROC is not possible, the physician can perform an IOL exchange where a 3-piece lens is placed, and ROC is done. “If the anterior capsulotomy won’t allow for that, we put the lens in the sulcus,” Dr. Fram said. With this option, she will fixate the lens to the iris gently, so it doesn’t move over time. In her research with Dr. Masket,5 ROC worked 96% of the time, and sulcus placement worked 86% of the time. Patients should understand that after ROC procedures early fibrosis of the capsule may occur, requiring a YAG posterior capsulotomy. Piggyback lenses can also be used, as can a secondary IOL on top of the lens to help scatter light, which worked 73% of the time. Bag-to-bag exchange has
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