Surgery for a congenital lens coloboma is challenging because the deformed capsular bag can lack focal, essential structural support. In these cases, the zonules are often missing in a specific sector, causing the bag to be weak, indented, and deformed. The surgical strategy must prioritize stabilizing this fragile environment to prevent the bag from collapsing or “zipping” open during the procedure. The initial capsulorhexis is particularly delicate, as the lack of tension in the coloboma area makes the capsule floppy and difficult to tear predictably. To compensate for the missing support, surgeons can sometimes employ a Capsular Tension Ring (CTR) to provide 360-degree outward expansion. This redistributes tension from the healthy zonules to the weakened area, maintaining the bag’s circular shape. If the defect is extensive, spanning more than 90 to 120 degrees, a specialized Cionni CTR or a Capsular Tension Segment (CTS) may be sutured directly to the sclera for permanent fixation. Final lens selection is equally critical, as the inherent asymmetry of the bag can cause a standard intraocular lens to decenter. Our guest surgeon uses a three-piece IOL to ensure the optics remain properly aligned over the visual axis. What are your best pearls for operating on these challenging eyes? Please comment below.
