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47 EW FEATURE May 2015 Secondary glaucoma challenges by Ellen Stodola EyeWorld Staff Writer because there is a tacky nature to the acrylic material, and the haptics are thick and square edged. The tacky surface will cause the pigment to abrade or erode away from the back surface of the iris," he said. Any intraocular lens in a suscep- tible patient may induce pigment dispersions, Dr. Masket said, but this typically does not occur with silicone lenses or with 3-piece acrylic IOLs. But even the 3-piece AcrySof in a rare patient may cause signifi- cant pigment dispersion, he said. This problem can occur when a lens is out of the capsular bag O ne way that secondary pigmentary glaucoma can occur is when part or all of a single-piece lens is not in the capsular bag. This can cause a number of complications for the patient and can sometimes be confused as a retina problem. Jason J. Jones, MD, Jones Eye Clinic, Sioux City, Iowa; Samuel Masket, MD, clinical professor of ophthalmolo- gy, Jules Stein Eye Institute, David Geffen School of Medicine, Univer- sity of California, Los Angeles; and Garry Condon, MD, chair, Depart- ment of Ophthalmology, Allegheny General Hospital, Pittsburgh, com- mented on this issue and potential treatment plans. Causes Pigment dispersion occurs when something has abraded the posterior iris surface, Dr. Jones said. "This can happen in phakic eyes with a pos- terior bowing of the iris diaphragm and rubbing of the posterior iris against the lens and zonules." Often this is associated with mild to mod- erate myopia, in males, and presents in a patient's 30s or 40s, he said. "Physical activity precipitates a significant shedding of pigment and Handling secondary pigmentary glaucoma AT A GLANCE • Secondary pigmentary glaucoma may sometimes be confused and misdiagnosed as a vitreoretinal problem. • The most important part of treat- ment is to remove the offending aspect of the lens implant. This could include an IOL exchange or repositioning of the lens. • A patient without primary glaucoma who develops secondary glaucoma as a result of pigment dispersion should not require a follow-up glaucoma procedure, as long as the issue is treated. Retroillumination defects temporally in the shape of the haptic that is in the sulcus Source: Jason J. Jones, MD continued on page 48 an acute elevation of IOP," he said. "With sufficient pigment liberation, the eye will manifest iris transillu- mination defects [TIDs], deposition of pigment on the corneal endo- thelium [Krukenberg's spindle], and angle pigmentation along the trabecular meshwork with greater deposition inferiorly as the heavier pigment settles with gravity." Dr. Jones said that this issue could also occur in pseudophakic eyes if the IOL surface comes into contact with the iris. "It should be mentioned that any IOL may induce this syndrome," he said. "There are certain IOLs and positions of lens material that are more likely to cause pigmentary dispersion and glaucoma." For example, single-piece acrylic IOLs are the most likely to cause it because not only are they the most popular lens design implanted, but the material is thicker in the haptic than a 3-piece design, often with a square edge and rough finish. "Because these haptics do not carry much tension, it is possible to implant the lens in a so-called bag-sulcus fixation (one haptic in the bag and the other in the sulcus) and still have the appearance to the surgeon of a centered IOL with both haptics correctly placed in the bag," he said. Intraoperative pupillary miosis can often occur, and this can mask the misplacement of the lens, Dr. Jones said. "The lens may appear to be well centered throughout the postopera- tive course," he said. "Typically sus- picion of the problem doesn't occur until months or years later." Theoretically it could happen with almost any type of lens implant that is in the posterior chamber and not in the desired position, Dr. Condon said. This is a particular problem with single-piece acrylic lenses because they have sharp/ square edges on the lens haptics and square edges on the lens optic. When the square edge is outside the capsular bag, it has the opportunity to chafe the ciliary body, he said. "I think the problem is a little less common now than it used to be," Dr. Condon said. This could be attributed to the fact that surgeons have come to expect these types of lenses to cause this problem. "Typ- ically, it's a delayed onset," he said. It doesn't happen usually in the first weeks or even months. Symptoms to be aware of are blurred vision, elevated eye pressure, and recurrent bleeding, often into the vitreous cavity. This issue can occur with contact of the posterior iris and the intraocular lens in either a suscepti- ble patient or with a given lens, Dr. Masket said. "The lens that's most commonly associated with this is the AcrySof lens [Alcon, Fort Worth, Texas]