34 EWAP DECEMBER 2023 CATARACT resistance during insertion, the surgeon should remove it and attempt insertion in the opposite direction,” he said. “There are other ways to insert a CTR with an inserter, including a Sinskey-guided insertion or a suture-guided insertion. These techniques help guide the leading tip of the CTR around the equator of the capsular bag.” Alternatively, the CTR can be inserted manually with the assistance of a Sinskey hook in the distal eyelet and a Kuglen hook guiding the CTR into the bag, Dr. Hart said, adding that he most often uses a disposable inserter. Several methods for placement of the CTR have been described in the literature, Dr. McKee said. “I currently use the preloaded CTRs from Bausch + Lomb, as they are high quality, easy to insert, and come preloaded in a sterile disposable injector,” he said. “These come in right- and left-handed orientation, but by simply inverting the injector, the orientation can be reversed. With the preloaded CTR, I insert the tip of the injector into the capsular opening and slowly inject the CTR.” The terminal trailing eyelet will be engaged by a small rod/hook in the injector advancing the CTR. Once this hook is fully advanced, the CTR can be disengaged from the injector with a second instrument or often by simply elevating the hook and having the CTR fall into the capsule. Dr. McKee noted that it is important that the capsule is intact for proper placement of a CTR. “A CTR should not be placed in the ciliary sulcus,” he said. “The capsule should be intact for CTR placement to prevent loss of the device into the vitreous cavity.” He also mentioned that the ‘S’ sign when placing a CTR is an important warning that should alert the surgeon to stop and attempt a different manner of CTR placement, noting an article from the Journal of Cataract & Refractive Surgery that discussed this. 1 Additional considerations Dr. McKee cautioned that when using a CTR, you should avoid sulcus placement or attempted placement in a torn/broken capsule. Other problems can accompany zonular damage, Dr. McKee said, such as vitreous prolapse, iris damage, peripheral retinal tears, and cystoid macular edema. “A CTR is often used in a complex case, and a high index of suspicion for other problems should be present.” Dr. Hart said that as a general rule for three or less clock hours of zonular dialysis, you can use a standard CTR. If the dialysis is T he simple capsule tension ring (CTR) and its several modifications are very useful tools in the armamentarium of cataract surgeons. The choice of ring and timing of insertion depend on the nature and extent of zonular dehiscence. In progressive zonulopathy such as Marfan’s or Weil Marchesani syndrome, the patient is often young, and despite a single point fixation with a single islet CTR, there is a chance the zonular weakness will progress over the patient’s lifetime. Despite a stable fixation, many of these eyes will have late decentration of the IOL-capsular bag complex, even with a 9-0 polypropylene. Therefore, I now prefer to use a double-islet CTR, or the combination of a single-islet CTR with an Ahmed segment in such cases, and fixate it to the scleral wall using a non-biodegradable suture (8-0 polytetrafluoroethylene). With non-progressive zonulopathy, such as trauma, or localized iatrogenic zonular dialysis, if the zonular loss is up to 3 clock hours, I would insert a simple CTR, whereas a single islet CTR would be sufficient for any loss between 3 to 6 clock hours. As for the timing of insertion, my views are the same as most surgeons, and I prefer to insert the ring at the end of cortex removal, wherever possible. Pseudoexfoliation and high myopia are both often associated with diffuse zonulopathy. I do not insert a CTR as a routine in both these situations, unless I find a diffuse laxity of the zonules. Although the CTR will help in redistributing the forces equally in the bag, I am not sure if it can prevent the consequences of this progressive form of zonular weakness. A useful tip for inserting the CTR, when it is done manually, is to thread one islet of the CTR with a 10-0 nylon suture. This way, if the CTR punctures the capsule, or is misdirected into the ciliary sulcus, it can be retracted by pulling on the suture. In summary, every surgeon should be conversant with implanting a simple CTR at the least, and as has been commented upon by the surgeons in this feature, practicing these in eyes with mild or suspect zonular weakness is a good idea to master the technique and its nuances Editors’ note: Dr. Vasavada receives occasional research support from Alcon Laboratories. Vaishali Vasavada, MS Consultant, Raghudeep Eye Hospital, Ahmedabad. Jaipur. India Email: vaishali@raghudeepeyeclinic.com Website: www.raghudeepeyehospital.com ASIA-PACIFIC PERSPECTIVES
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