EyeWorld India September 2020 Issue

EWAP SEPTEMBER 2020 25 CATARACT epinephrine on every patient. “The truth of the matter with IFIS is patients aren’t sure if they are on an alpha blocker,” he said, adding you have to assume they’re taking tamsulosin. Because of his “paranoia” about this, Dr. Oetting also avoids mechanically stretching the pupil because it can make IFIS worse. Dr. Koch finds that mechanical stretching tends to create asymmetric tears and, likewise, he has stopped doing this. For patients with small pupils, Dr. Oetting tends to use the Malyugin ring, which doesn’t require any additional incisions that can affect the fluid dynamics of the chamber. He reserves iris hooks for cases with narrow angles with posterior synechiae. “In that situation, I’ll simultaneously lyse the synechiae and place the iris hooks,” Dr. Oetting said. Stabilizing possibilities All hooks are not the same. For stabilizing the bag, Dr. Oetting finds capsular tension hooks, sometimes known as capsule retractors, are useful when zonules are weak and there is concern that they may not hold up to nuclear fracture. “The idea is you’re stabilizing the bag while you’re doing nucleus removal,” Dr. Oetting said. Typically, he likes to place these retractors before nuclear fracture. Once the bag is empty, he places a capsule tension ring and assesses whether he needs another device, such as a sutured capsular tension segment. Whenever Dr. Koch thinks the capsule is so weak that the lens will subluxate posteriorly, he relies on either Mackool hooks (FCI Ophthalmics) or MicroSurgical Technology (MST) capsular hooks. With the MST hooks, he prefers the newer model that has a smaller opening that prevents it from getting entangled with the capsular tension ring. He also finds the Mackool hooks are easy to use. “They’re placed as early as I need to assure good stability,” he said. “The other ‘device’ that I use when I’m removing the nucleus is a lot of dispersive OVD, Healon EndoCoat [3% sodium hyaluronate, Johnson & Johnson Vision]. Injecting this into the bag provides a great cushion and prevents the bag from collapsing into the phaco tip.” If needed, he may also insert a capsule tension ring for additional support during phacoemulsification. In these instances, a scleral-fixated Ahmed segment (or two) is almost always used to assume long-term capsular stability. Capsule tension rings can make cortex removal more challenging, so Dr. Koch recommends viscodissecting away from the capsule before trying to aspirate it in order to minimize traction on the capsule. EWAP Editors’ note: Dr. Koch is Professor and Allen, Mosbacher, and Law Chair in Ophthalmology Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, and has relevant interests with Alcon and Johnson & Johnson Vision. Dr. Oetting is professor of ophthalmology, University of Iowa, Iowa City, Iowa, and declared no conflicts of interest. Vaishali Vasavada, MS Consultant ophthalmologist, Raghudeep Eye Hospital, Ahmedabad, India vaishali@raghudeepeyeclinic.com ASIA-PACIFIC PERSPECTIVES T his article discusses the relevance and the particular pros and cons of using various hooks and rings in cataract surgery. Small pupils, either preoperatively or developing midway during surgery block visualization and also risk iris injury if not dealt with appropriately. Iris retractors have been time tested to stretch and mechanically dilate small pupils. The advantages with using these is that they are easy to insert even when there is a shallow anterior chamber and a fibrotic pupil. In fact, these can even be used to mechanically lyse posterior synechiae and thereby can serve a dual purpose. Two key points to remember when inserting iris hooks are: They need only a very small incision for insertion, and injecting dispersive OVD underneath the iris at the site of hook insertion makes it easier to place these hooks. The other advantage I find with using hooks is that they can be inserted even midway during surgery if the pupil becomes small. Further, I have sometimes even used the same hooks to anchor the capsular bag in cases where unexpected intraoperative zonular weakness is found. However, they do cause tenting up of the iris, especially in the subincisional areas and thereby iris chaffing during phacoemulsification may be more pronounced. In contrast, the Malyugin ring offers the advantage of easy insertion and extrusion through a small incision and avoids irregular sphincter tears in the pupillary margin. It may, however, be challenging to implant, especially in an eye with a shallow anterior chamber and an extremely fibrotic pupil margin. Zonular weakness becomes much easier to deal when the right devices are used. Capsular hooks are blunt and broad tipped, and can support the capsular bag without the risk for injury to the capsular fornices. Capsular tension rings with or without fixation elements are an excellent means of stabilizing the capsular bag. In combination with a meticulous surgical technique and use of OVDs, the capsule can not only be supported, but surgery can be successfully completed with implantation of an IOL in the bag. The key message to be taken from this article, however, is that today, there is a plethora of options available to surgeons that help us smoothly navigate cases with small pupils and zonular weakness of varying degrees. Selecting the right one for you, based on a combination of personal experience as well as each device’s merits and demerits helps surgeons deliver the best of outcomes even in these challenging cases. Editors’ note: Dr. Vasavada declared no relevant financial interests.

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