OCT 2013

EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.

Issue link: https://digital.eyeworld.org/i/194331

Contents of this Issue


Page 98 of 134

96 EW RESIDENTS October 2013 Cataract M&M rounds Chopped A 70-year-old man presented with gradual decline in vision, and we diagnosed him with a functionally significant cataract.KHe had few systemic medical issues, and we performed his surgery under topical anesthesia with a third year resident in our program. The anterior capsulotomy was continuous. The resident performing the case had good control of both hands and was transitioning to chopping techniques with stop and chop nucleofractis. The case went fairly smoothly until the chopper was placed too anterior and stressed the zonules (Figure 1).KThe residual nuclear and cortical material was removed with care and a CTR was placed to support the weakened area of zonules.KA single-piece acrylic IOL was placed, which centered nicely and has remained centered for several months. We are fortunate to have the advice of three outstanding resident surgery mentors for this case. We asked them these questions: How would you help to prevent this problem? After you detect a weakened area of zonules, what do you do differently to help the case move safely along?KAny tips for placing the CTR in this case? Thomas Oetting, MD, Cataract M&M rounds editor Preston H. Blomquist, MD Dr. W. Maxwell Thomas Chair in Ophthalmology, University of Texas Southwestern Medical Center, Dallas This is every faculty's nightmare— staffing the resident who places the horizontal chopper above the anterior capsule. Either the zonules are disrupted or, worse yet, the resident cleaves the capsular bag. When teaching chopping, I have residents hydrodelineate as well as hydrodissect. Residents then slide the chopper peripherally in the space between the cortex and the nucleus created by hydrodelineation. By sliding under the anterior cortex with the chopper, one doesn't have to worry about accidentally placing the chopper above the anterior capsule. The stop and chop nucleofractis technique, as was used in this case, is great for the resident just learning chopping as it not only creates space in the eye to pull the nuclear half centrally to make room for passing the chopper, but also allows the resident to directly visualize the thickness of the nuclear half and embed the phaco tip securely in it. I have also started teaching vertical chopping earlier to residents as it does not require the chopper to pass under the capsulorhexis, although a firm "grip" on the nucleus by the phaco tip is required to counter the downward force of the vertical chopper. As soon as an area of zonular dehiscence is identified, I have the resident isolate the area with a dispersive viscoelastic. If there is any question as to whether vitreous prolapse has occurred, triamcinolone (either preservative-free or "washed" to remove the benzyl alcohol preservative1) diluted to 4 mg/mL with balanced salt solution may be injected into the anterior chamber in order to visualize vitreous strands. If there is no vitreous prolapse, the case may proceed with care taken to minimize any force on the capsular bag. Tangentially stripping the cortex from the bag (as opposed to stripping the cortex centrally) may help prevent extension of zonular dehiscence. A capsular tension ring is inserted if there are four clock hours or less of zonular dehiscence. If there are more than four clock hours, the Cionni modified CTR or Ahmed capsular tension segment are more appropriate if in-the-bag IOL placement is still preferred. The rule of thumb is that the CTR is placed as late as possible in the case, preferably just prior to IOL insertion. The capsular bag is filled with a cohesive viscoelastic and the CTR is introduced either with a Geuder injector, as in this case, or without an injector by feeding the CTR slowly into the eye using non-toothed forceps and a Sinskey hook to allow it to "snake" around the fornix of the capsular bag (sometimes forgoing the injector may be preferable if the resident has trouble inserting the injector and allows escape of viscoelastic). The CTR allows centration of a one-piece acrylic lens and assures that the faculty will have pleasant dreams postoperatively. Reference 1. Burk SE, Da Mata AP, Snyder ME, Schneider S, Osher RH, Cionni RJ. Visualizing vitreous using Kenalog suspension. J Cataract Refract Surg 2003; 29:645-651. Ayman Naseri, MD Vice chair, residency program director, Stephen P. Shearing Chair in Ophthalmology, Department of Ophthalmology, University of California, San Francisco (UCSF) Ophthalmology chief, San Francisco Veterans Administration Medical Center We encounter this situation quite commonly as our residents transition from divide and conquer to horizontal quick chop (or "non-stop chop," i.e., no initial groove). As a starting point, we advocate that beginning choppers perform thorough hydrodelineation in addition to standard hydrodissection. The epinuclear "cushion" is helpful as one traverses this learning curve. Since horizontal quick chop requires the resident to place the chopper around the equator and hook the endonucleus, avoidance of the anterior capsule is essential to mastering this technique. One of the advantages of stop and chop as a transition to quick chop is that the initial groove creates intracapsular space that allows the heminuclei to be somewhat mobile. In many cases, the surgeon continued on page 98 Figure 1: Chopper was placed too anterior and stressed the zonules

Articles in this issue

Archives of this issue

view archives of Eyeworld - OCT 2013