EyeWorld Asia-Pacific March 2014 Issue

March 2014 18 EWAP FEAturE Using triamcinolone in the anterior chamber by Michelle Dalton EyeWorld Contributing Writer AT A GLANCE • Triamcinolone should be used in a preservative-free preparation and is both diagnostic and therapeutic. • Triamcinolone isn’t helpful in the presence of viscoelastic which blocks particulate identification of vitreous. • Triamcinolone is most useful at the end of vitrectomy to ensure no wayward strands are left and as the last maneuver to identify any representation of vitreous prolapse. Experts share their technique pearls, as well as optimal time for use I t’s not often vitreous comes forward during anterior segment surgery, but when it does the ability to see where the vitreous is to fully remove it is crucial. For years, surgeons have been using triamcinolone in an off-label indication to help visualize the vitreous, with most surgeons following the methods first described by Scott E. Burk, MD, PhD , in 2003. 1 (Gholem Peymen, MD, first discovered particulate identification of the vitreous in the posterior segment with triamcinolone.) Kenalog (triamcinolone acetonide, Bristol-Myers Squibb, New York, NY, U.S.) “is a preserved medication, so when Dr. Burk wrote his seminal article, he showed how to remove the preservative with an 18[-G] filter needle,” said Lisa B. Arbisser, MD , Eye Surgeons Associates, Bettendorf, Iowa, U.S., and clinical adjunct associate professor, University of Utah, John A. Moran Eye Center, Salt Lake City, Utah, U.S. The process was time consuming, and some people opted to use it “as is,” preservatives and all, she said. Preservatives are not necessarily as much a concern during posterior segment surgery “but they’re not healthy for the endothelium; Kenalog specifically notes it is not for ophthalmic use, so it must be diluted and prepared for the off-label use,” she said. Triesence (triamcinolone acetonide, Alcon, Fort Worth, Texas, U.S.) “is in a preservative free medium, has a code so we can get paid for it and is on-label, so I no longer use Kenalog.” There are “numerous” versions of triamcinolone available off- label, including several that are preservative-free from compounding pharmacies, said Michael E. Snyder, MD , in practice at the Cincinnati Eye Institute, Ohio, U.S. For those who use the Kenalog meant for subcutaneous injection, “you need to wash off the triamcinolone crystals by suspending and aspirating it into a syringe, injecting the triamcinolone into a filter, resuspending it into a fresh syringe with balanced salt solution, and repeating that a few times to essentially wash off the crystals so the diluent in the commercial preparation doesn’t cause any hazards just as Dr. Burk’s original article describes,” Dr. Snyder said. Both physicians agreed injecting Kenalog directly into the anterior chamber is inadvisable because “the diluent has some preservatives and alcohol in it that can be toxic to endothelium,” Dr. Snyder said. When to use triamcinolone Dr. Snyder uses triamcinolone most often when he has planned a vitrectomy or during reconstruction cases. “The overwhelming majority of the time—and almost any time I’m using it—it’s at the beginning of the case,” Dr. Snyder said. “The challenge is that if you’re already in the middle of the case, depending on what viscoelastic (OVD) you’ve already used and how much has been aspirated … it’s very difficult to use triamcinolone in the presence of viscoelastic.” The triamcinolone crystals will “stick” to the vitreous but be blocked by the OVD, he said. “The idea is to have the crystals blow around in the aqueous, insert some into the anterior chamber, the whole chamber will turn white, and add a little balanced salt solution. Once you rinse away the excess, crystals are stuck to the surface of the vitreous gel.” In the “best of all worlds,” as soon as a surgeon thinks vitreous has been lost or had a break in the posterior capsule or had a complication, “you should immediately take out your second hand instrument and instill the diluted Triesence to see if there’s any vitreous presenting and whether you’ve broken the posterior capsule,” Dr. Arbisser said. Determine if the anterior hyaloid is intact, or whether there is prolapse of vitreous forward and a non- intact hyaloid, she added. In reality, though, most surgeons will fill the eye with OVD (preferably a dispersive one) which is immediately at hand in all cases rather than wait for the Triesence to get everything to a static position and inspect it carefully, Dr. Arbisser said. Putting triamcinolone into the chamber after the OVD prevents surgeons from seeing what is OVD and what is vitreous, Dr. Snyder added. Both surgeons also use triamcinolone at the end of a case after a vitrectomy to ensure all the OVD and vitreous is managed. “If the OVD is already there, Triesence is of little value to you because the OVD prevents the Triesence from getting to stain the vitreous. It won’t stain the OVD, but it’s blocked by the OVD from clinging to the hyaluronic structure of the vitreous. So the first thing you need to do if you run into trouble is decide if you need to do a vitrectomy,” Dr. Arbisser said. Pearls for use When using Triesence, Dr. Arbisser recommends diluting it 1:10 with balanced salt solution. “That way, it can last throughout the procedure, be used more than once and it doesn’t create a big, ropey strand of white stuff that blocks your view that you then have to then dilute inside the eye,” she said. Vitrectomy should be biaxial “so that the irrigation goes through the paracentesis and the bare vitrector needle either goes through a new paracentesis anteriorly or through a pars plana incision,” she advised. When a complication is recognized