EyeWorld Asia-Pacific December 2012 Issue

34 EWAP Cataract/IOL December 2012 removing the nucleus through a funnel shape incision whose internal width is greater than the external width is simple and easy. EyeWorld: You have worked as a volunteer surgeon in underdeveloped countries for many years. What motives you to take time out of your busy private practice to volunteer in this way? Dr. Colvard: We eye surgeons have been given a wonderful gift. Through our training we have been given the ability to help blind people see again. It’s a gift that’s so precious that we must share it, especially with those who need our help most desperately. In our private practices most of the surgery we perform is done to allow our patients to drive more safely or to read more easily. That’s important, but in Africa, Central and South America, India, and the Far East, as volunteer surgeons, we are usually doing surgery that is far more life changing. Our efforts allow patients to feed themselves again without help from family members, to walk unassisted, and to see their loved ones. This is an experience that no eye surgeon should miss out on. We have an extraordinary gift that’s ours to give, and it’s a shame for any of us to miss the wonderful opportunity to share our gift with those who need us most. EWAP Editors’ note: Dr. Colvard has no financial interests related to this article. Reference Ruit S, Tabin G, Chang D, et al. A prospective randomized clinical trial of phacoemulsification vs. manual sutureless small-incision extracapsular cataract surgery in Nepal. Am J Ophthalmol. 2007;143(1):32-38. Contact information Colvard: mike@mcolvard.com ECCE - from page 30 The cleavage of cortex from the capsule equatorially and anteriorly allows fluid to exit from the capsular bag via the capsulorhexis, which constricts to its original size (Figure 3), and mobilizes the lens in such a way that it can spin freely within the capsular bag. Repeating the hydrodissection and capsular decompression starting in the opposite distal quadrant may be helpful. Adequate hydrodissection at this point is demonstrable by the ease with which the nuclear– cortical complex can be rotated by the cannula. Following at least two cortical cleaving hydrodissection injections and rotation of the lens, we then perform hydrodelineation. 1,7 Hydrodelineation circumferentially separates the endonucleus from the epinucleus and facilitates mobilization of the endonucleus separate from the epinucleus. The epinucleus remains in the capsule and keeps the bag stretched throughout the procedure, thereby making it much more unlikely that a knuckle of capsule will vault anteriorly, occlude the phaco tip, and rupture. In addition, hydrodelineation reduces the size of the nucleus that has to be mobilized through disassembly and emulsification, thereby reducing the amount of energy into the eye. Circumferential division reduces the volume of the central portion of nucleus removed by phacoemulsification by up to 50 percent. This allows less deep and less peripheral grooving and smaller, more easily mobilized quadrants after cracking or chopping. Hydrodelineation thus creates additional safety and reduces the invasiveness of the procedure. Once all of the endonucleus has been mobilized we address the epinucleus. The bevel of the phaco tip is now turned up and the epinuclear rim and roof are purchased distally, in foot position two, pulled centrally and then swept with the phaco needle at a low power, in foot position three, to trim the roof and rim of the epinucleus. This is associated with mini-occlusion breaks and mini- surges, more pronounced with 19 gauge tips, which allow the cortex in that quadrant to flow over the rim of the epinucleus and into the phaco needle. The epinucleus is allowed to settle back and then is rotated twice more, and two additional quadrants of peripheral epinuclear roof and rim are mobilized along with the cortex under them. The final quadrant of epinuclear rim is rotated distally, purchased with the phaco tip in foot position 2, and pulled centrally, while the second handpiece is used to push the floor of the epinucleus, distally, thereby creating anti-parallel forces that flip the residual floor and last quadrant of the epinuclear rim upside down within the confines of the anterior chamber, removing it from its proximity to the posterior capsule, as it is mobilized mostly by vacuum with low power bursts of ultrasound energy. If there is residual cortex, more common with smaller gauge phaco tips, we simply sweep the cortical aspirator circumferentially around the capsulorhexis, port facing the fornix of the capsule, and easily bring the remaining fragments out. Because the connections to the capsule have previously been lysed by cortical cleaving hydrodissection, we rarely need to strip cortex centrally. If there are some fine strands of cortex still attached to the capsule, we find it efficacious to use a 0.2-mm aspiration port, compared to a 0.3-mm port, as it will occlude more easily. Prior to cortical cleaning hydrodissection, the majority of capsule ruptures during phacoemulsification surgery occurred during aspiration of the cortex. EWAP Editors’ note: This is a modification of Chapter 9 (pages 197-216), “Minimally Invasive Cataract Surgery,” in the book Minimally Invasive Ophthalmic Surgery published by Springer-Verlag Berlin Heidelberg, 2010. References 1. Fine IH. Cortical cleaving hydrodissection. J Cataract Refract Surg. 1992;18(5):508-512. 2. Faust, KJ. Hydrodissection of soft nuclei. Am Intraocular Implant Soc J. 1984;10:75-77. 3. Davison JA. Bimodal capsular bag phacoemulsification: A serial cutting and suction ultrasonic nuclear dissection technique. J Cataract Refract Surg. 1989;15:272-282. Contact information Fine: hfine@finemd.com Cortical - from page 33