CATARACT EWAP DECEMBER 2023 33 the sclera via the ciliary sulcus would be appropriate. For more than 180 degrees of zonular compromise, a Cionni ring with two eyelets for scleral fixation can be used.” Dr. McKee noted that it may sometimes be obvious ahead of surgery that a CTR or support segment will be needed. In other cases, the zonular weakness may not be apparent until during surgery. “The ideal time to place the CTR is after cortical cleanup and prior to the placement of the IOL in the capsule,” he said. “In some cases, the cortical cleanup may cause worsening zonular weakness. In these cases, the CTR can be placed prior to cortical cleanup to stabilize the capsule, but this could make cortical cleanup more difficult.” When to use a CTR Dr. McKee said that certain genetic conditions, such as Marfan syndrome, Weill- Marchesani syndrome, or Ehlers - Danlos syndrome, are associated with zonular abnormalities. “Support segments may be required during cataract surgery for these cases,” he said. Trauma is likely the most common cause of focal zonular damage, he said. Pseudoexfoliation syndrome is associated with global zonular weakness and late dislocation of an IOL-capsule complex. The placement of a CTR in pseudoexfoliation does not necessarily increase support for the capsule or prevent late dislocation of the IOL, Dr. McKee said, but it may help to reduce capsule phimosis, and it does offer a stable substrate for fixation of a subluxated IOL-capsule complex that can occur many years after the original cataract surgery. In cases where a single-piece toric acrylic IOL is used, Dr. McKee said some surgeons think that a CTR can help to reduce the postoperative rotation of the toric IOL. The Henderson CTR may be especially useful due to the undulating design. Highly myopic eyes with a deep anterior chamber and/or a large capsule may be better candidates for using a CTR to help prevent rotation of a toric IOL, he said. Dr. Hart said that he uses a standard CTR in all his pseudoexfoliation syndrome cataract cases, all cases with documented blunt trauma, cases with zonular dialyses, and cases where he visualizes the equator of the capsular bag (indicates stretched zonules). “I commonly use CTRs in patients with an axial length greater than 26 mm. I use them routinely in patients with an axial length greater than 26 mm where I am placing a toric IOL. If I have to reposition a toric IOL because it has rotated to the wrong axis, I will routinely use a CTR. I place the CTR at the first sign of zonular instability,” he said. Methods for best placement CTRs can be placed with an inserter or manually, Dr. Hart said. He added that there are reusable inserters, and there are preloaded disposable inserters. The reusable inserters are made to insert the CTR in a clockwise manner. The disposable inserters can insert the CTR in a clockwise or counterclockwise manner. Dr. Hart added that the direction of insertion can be important, depending on where the zonular weakness is localized in relation to the main incision. “If the CTR encounters Traumatic zonular dialysis. Traumatic zonular dialysis.
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