Eyeworld

EW GLAUCOMA 48 by Brian A. Francis, MD Utilizing ECP for effective glaucoma management E ndoscopic cyclophotocoag- ulation (ECP) is a surgical technique that decreases production of aqueous fluid by applying laser energy to the ciliary processes and thereby disabling the epithelial layer of the process. Typically, ECP is per- formed from an anterior approach and through a clear corneal incision. Here is how I successfully treat patients with ECP. Surgical procedure For an anterior segment glaucoma patient, I use two limbal corneal incisions so that I can access 360 degrees of the ciliary processes. The two incisions are at least 90 degrees or more apart to maximize the treat- ment. I use a curved endoscope (Endo Optiks, Little Silver, N.J.) for better access to the far reaches of the process on either end. The settings on the instrument are fairly stan- dard. I use a power of .25 to .3 watts, which can be titrated up or down depending on how well the tissue is taking up the laser and how close I am to the processes. Sometimes when I am at the extreme ends of treatment, instead of treating straight ahead I treat from the left or right side. I am then much closer to the process, so I lower the energy delivery accordingly. Typically, I try to get as much of the 360 degrees of the processes as I can. Because I am using an anterior approach, I am not accessing the entire process, only the anterior two-thirds. I place the laser setting on continuous so that laser energy is being delivered as long as I am pressing the foot pedal. That allows me to use a spray paint- ing technique wherein I put the aiming beam on the process and press down the pedal; I can treat that process all the way up and down as well as the process next to it and do so in a continuous pattern rather than with discreet laser spots. At the end, I look for whitening and shrinking of the entire process. I go over it in one direction, and as I come back I treat a little more where necessary and especially in between each process to fully treat the ciliary epithelium. Once I am done with one incision, I move to the other incision and treat the rest of the processes. I make sure that I am not overtreating by heating up the process so much that it disrupts the tissue or it explodes, causing a pop- ping sound. This will lead to inflam- mation and possibly pain and bleeding in the eye. Because I can see the tissue reaction, I can titrate the laser energy delivery. This is the primary difference with transscleral cyclophotocoagulation, where overtreatment occurs and the ciliary processes may explode. It is critical to inflate the ciliary sulcus space ad- equately with viscoelastic. I usually use Healon or Healon GV (Abbott Medical Optics, Santa Ana, Calif.) because it does not form bubbles from the laser. I inflate the ciliary sulcus so the iris is pushed forward and even touching the peripheral cornea, which allows a good view and approach to the ciliary processes. Without good inflation, you end up treating tissue you shouldn't be treating, like the posterior surface of the iris. Postoperative treatment After I am finished, I thoroughly clean the viscoelastic out of the eye; this is essential to prevent pressure spikes. There is a lot of viscoelastic behind the iris, which is not typical with other procedures. Therefore, I spend extra time with the irrigation and aspiration, whether it is auto- mated with phaco or manual with an irrigation/aspiration cannula. Flushing the anterior chamber with balanced salt solution is not suffi- cient to remove all viscoelastic. I treat inflammation aggressively with a preservative-free dexamethasone that can be injected in the anterior chamber. If the patient is prone to inflammation, I may administer a dose of IV steroids during surgery or orally in the immediate postop pe- riod in addition to frequent topical steroids. To prevent IOP spikes, I keep patients on their glaucoma medications. If they are fragile and have advanced glaucoma, I will not hesitate to put them on an oral car- bonic anhydrase inhibitor to main- tain their pressure until I see them postoperatively. Starting at postoper- ative week 1 to 4, I titrate the pa- tient down or off of glaucoma medications. I also titrate or stop steroids as able and discontinue the antibiotic drops at 1 week. I see the patients for follow-up at 1 day, 1 week, and 2 to 4 weeks postop. Case presentation An 83-year-old Caucasian female presented with primary open angle glaucoma, a cup to disk ratio of 0.85–0.9 OD and 0.9 OS, an IOP of 14 mmHg OD on one medication and 23 mmHg OS on three medica- tions. She previously had posterior chamber IOLs implanted in both eyes and an Ahmed tube shunt implant OD. Although the IOP was controlled, she was experiencing strabismus and constant diplopia postoperatively and desired tube explantation. She refused tube shunt revision or replacement and wanted a low-risk surgery, so we performed ECP with the tube shunt removal. Postoperatively, the patient's IOP was controlled in the mid teens with dorzolamide-timolol fixed combination. Her diplopia and strabismus resolved. One of the advantages of ECP is that it is an internal procedure, so I can perform it in a patient who has ocular surface disease and scleral thinning, conjunctival scarring, or other conditions that would nor- mally prevent or limit my success with a traditional surgery, such as trabeculectomy or tube implanta- tion. It's also useful because it's the only procedure that addresses aque- ous production, so if the patient has had prior filtration surgery, be it standard filtration surgery or mini- mally invasive glaucoma surgery, ECP is a good adjunct to those treat- ments if they fail or if I want to achieve additional pressure lowering with a combined procedure. EW Editors' note: Dr. Francis is the director of glaucoma services at the Doheny Eye Institute, and professor of ophthal- mology at the UCLA Geffen School of Medicine, Los Angeles. He has financial interests with Endo Optiks. Contact information Francis: bfrancis@doheny.org February 2011 May 2014 Brian A. Francis, MD Microscope view of endoscope during ciliary process treatment. This eye has an anterior chamber maintainer due to aphakia and prior vitrectomy. Source: Endo Optiks

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