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EW RESIDENTS 50 July 2014 Swiss cheese Shameema Sikder, MD Assistant professor of ophthalmology, cornea, cataract and refractive surgery Johns Hopkins University, School of Medicine Medical director, Wilmer Eye Institute, Bethesda, Md. Unfortunately, iris strike can be a problem for the novice and experi- enced surgeon alike. While this may happen with floppy iris patients, it can also sometimes be an issue in myopes with deeper anterior cham- bers. In general, I suggest to my resi- dents that phacoemulsification take place in the iris plane as close to the visual axis possible. I find that this area of the anterior chamber is often the deepest and permits complete visualization of the tip of the phaco probe. I often say that if you cannot see where the tip of the phaco probe is, assume you are about to phaco something bad—like iris or posterior capsule. Keeping the tip of the phaco probe in the center of the anterior chamber also encourages the surgeon to keep the globe neutralized and minimize rotation. Furthermore, working in the central anterior chamber permits safe distance from the cornea, reducing potential damage during pha- coemulsification and instrument manipulation. In order to prevent the iris strands from interfering with the remainder of the case, I would con- sider putting a single iris hook in with a 25-gauge needle on an empty syringe. I find that using the needle at the limbus creates a tract that is of adequate dimension through which the iris hook easily passes. Also, using a single hook will ensure that the iris doesn't sustain any further damage during the case including in the irrigation/aspiration phase. For the remainder of the case, keeping the instrumentation in the center of the anterior chamber will also minimize further manipulation of the iris. It may also help to drop the bottle height of the phaco ma- chine infusion to allow the anterior chamber to be a bit more stable and keep the iris from oscillating toward the center. Figure 1. The resident bored through the nuclear quadrant and caught the iris. Figure 2. The iris was injured a bit with a frayed pupil margin and some transillumination defects across from the wound. Source (all): Thomas A. Oetting, MD A 70-year-old with a visually signifi- cant cataract presents for cataract surgery. The patient denied the current use of alpha-blockers but did have a history of transurethral prostate surgery years ago. The resident doing the case had more than 100 phacoemulsification cases as primary surgeon. The case was proceed- ing nicely until the pupil came down a bit during nucleofractis. The resident bored through the nuclear quadrant and caught the iris (Figure 1). The iris was injured a bit with a frayed pupil margin and some transillumination defects across from the wound (Figure 2). The rest of the case was uneventful. Thomas Oetting, MD, Cataract M&M rounds editor Cataract M&M rounds How would you prevent strikes of the iris such as this? How would you prevent the iris strands from interfering with the remainder of the case? 50-53 Residents_EW July 2014-DL_Layout 1 6/30/14 8:49 AM Page 50

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