CATARACT 32 EWAP DECEMBER 2023 A capsular tension ring (CTR) can be a useful tool for ophthalmologists to have on hand during surgery. Two physicians discussed the available products, when the best time is to use them, and methods for good placement. John Hart Jr., MD, said there are three CTR products that he routinely uses: a standard CTR, a Cionni CTR, and the Ahmed capsular tension segment. “I use a CTR in approximately 10% of my cataract cases,” Dr. Hart said. “Patients with zonular abnormalities are commonly referred to me by other ophthalmologists. I think that most ophthalmologists don’t use them as frequently as I do.” When a CTR is properly positioned in the capsular bag, it distributes support from areas with intact zonules to areas with weak or missing zonules, Dr. Hart said. The CTR also keeps the equator of the capsular bag expanded in areas where zonules are missing. “This is important because if zonules are missing and the cataract is being removed, the equator of the bag will collapse inward, increasing the likelihood of damaging the capsular bag with the phacoemulsification or I/A tip,” he said. “If the equator of the bag collapses inward, there is also a much greater chance of vitreous loss and subsequent vitreous - retinal complications.” Dr. Hart said that the CTR should be placed “as late as possible but as early as you need it,” adding that this is a direct quote from Kenneth Rosenthal, MD. “In the FDA trials for the standard Morcher CTR, we placed the CTR after hydrodissection,” he said. “I commonly place the CTR after cortical cleanup. That way I don’t trap cortex between the CTR and the capsule.” Yuri McKee, MD, noted that there are several different types, sizes, and manufacturers of CTRs. “Most designs are a simple, smooth ‘C’ ring with eyelets at the terminal ends,” he said. “Sizing is typically done using the white - to - white measurement as a surrogate for capsular diameter.” He said the Henderson CTR has undulations on the ring designed to allow Contact information Hart: j.c.hartjr@sbcglobal.net McKee: mckeeonline@mac.com Using CTRs in practice by Ellen Stodola Editorial Co - Director for the removal of cortex from behind the CTR. More specialized CTRs, such as the Ahmed segment or Cionni ring, are designed to allow for scleral fixation of the device in the case of severe zonular compromise, he said. Dr. McKee said he uses a CTR if focal zonular compromise is noted, either prior to or during surgery. “This is around 5% of my cases, but as a referral practice, I probably see more cataracts with zonular deficiency than average,” he said. A basic CTR is designed to redistribute the strength of healthy zonules to areas of zonular weakness. “Up to 90 degrees of continuous zonular weakness can be remedied with a basic CTR,” he said. “If 90–180 degrees of zonular damage are present, one or two Ahmed segments secured to Ahmed capsular tension segment that has just been inserted; a 9-0 prolene suture is threaded through the fixation element. This article originally appeared in the September 2023 issue of EyeWorld. It has been slightly modified and appears here with permission from the ASCRS Ophthalmic Services Corp.
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