EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/387844
EW CATARACT 43 by Lauren Lipuma EyeWorld Staff Writer Creating a capsulorhexis in white cataracts without trypan Cataract expert says that operating without a capsular staining technique will increase a surgeon's technical skills C apsular staining techniques provide several advantages when operating on white intumescent or mature cat- aracts, but in most cases, surgeons can operate without them, said Reena Sethi, MD, Arunodaya Deseret Eye Hospital (ADEH), Gurga- on, Haryana, India. Speaking at the Women in Ophthalmology (WIO) 2014 Summer Symposium, Dr. Sethi presented pearls and techniques for making a capsulorhexis in white cat- aracts without staining the capsule, explaining that operating without trypan blue increases a surgeon's confidence and technical skill. Why operate without trypan? While many surgeons use trypan in cases of intumescent, hyperma- ture, or mature cataracts, Dr. Sethi believes that with the proper tech- nique, the anterior segment surgeon would only need to use trypan blue in cases of traumatic or pediatric cataracts or corneal opacities. A 2012 study published in the Journal of Cataract & Refractive Surgery revealed that there is no difference in capsulorhexis strength between stained and non-stained capsules, Dr. Sethi said, and staining with trypan blue did not reduce tear resistance. Learning to operate without trypan may be especially useful for surgery in the developing world, she added, so it is sensible for physicians who are considering international charity work to learn. "The message I want to tell everyone is that it will actually increase your surgical skills when you don't use trypan blue because you will [become] more confident, you [become] more focused onto the capsule, and you will improvise newer methods of visualizing the capsule," she said in a video interview with EyeWorld. Achieving good visualization Without a staining technique, prop- er visualization becomes paramount, Dr. Sethi said, so a quality micro- scope is indispensible. To increase visualization, she recommends coating the anterior surface of the cornea with viscoelastic. This will hydrate the ocular surface, keep the patient from startling when fluid is applied to the eye, provide clarity, and aid in the magnification seen through the scope. Keep a sharp focus on the anterior capsule, she stressed, and position the eye to optimize the red reflex. Additionally, be sure not to put any stress on the instruments or the eye—use gentle, subtle movements, without adding any downward pres- sure. When you feel as though you are losing control of the capsulor- hexis, add more viscoelastic, regrasp the edge, and continue, she said. Surgical techniques When a milky cortex causes the in- tralenticular pressure to increase dra- matically, make a small puncture at the center of the capsule, and aspi- rate the cortex to lower the pressure. This will prevent the capsulorhexis from tearing out into the periphery. She recommends maintaining a deep anterior chamber with a heavy, cohesive viscoelastic and making a small nick right in the center of the capsule. After making that initial punc- ture, aspirate the milky cortex, add more viscoelastic (which will help to visualize the capsule), and begin the capsulorhexis. Dr. Sethi's technique of pinching the anterior capsule right at the center to relieve the pressure caused by a milky cortex. Source (all): Reena Sethi, MD "The important thing is not to go in and out of the anterior cham- ber often, keep the anterior chamber formed, and visualize your capsule as best as you can," she said. When there is a fibrotic plaque at the center of the capsule, make a capsulorhexis around the plaque using a 2-stage method. First, make a small capsulorhexis around the plaque—never go toward the cen- ter—and when you feel comfortable, make a second cut and extend the rhexis, she said. Next, perform a gentle hydrodissection and keep phaco parameters low, as it is likely that the zonules will be weak. Final thoughts Remember that making the cap- sulorhexis without trypan blue is doable, said Dr. Sethi, and do not worry if you have lost the leading edge. "Whenever you've lost control of your [continuous curvilinear capsulorhexis], viscoelastic has to be taken again to push back the capsule, get the leading edge again, decrease the angle force applied, and try bringing the rhexis back toward the center." A successful capsulorhexis is the key to achieving good results in operating on white cataracts, she concluded, and proper visualization and steady surgical hands can aid a surgeon without a staining tech- nique. EW Reference Jaber R, Werner L, Fuller S, Kavoussi SC, McIntyre S, Burrow M, Mamalis N. Compar- ison of capsulorhexis resistance to tearing with and without trypan blue dye using a mechanized tensile strength model. J Cataract Refract Surg. 2012 Mar;38(3):507–12. Editors' note: Dr. Sethi has no financial interests related to her comments. Contact information Sethi: acteyecare@gmail.com October 2014