Capsular tension ring
Circular device implanted to stabilize the lens capsule during cataract surgery when zonular support is compromised.
Full Definition
A capsular tension ring (CTR) is a flexible, circular polymethylmethacrylate (PMMA) device inserted into the capsular bag to provide circumferential support when zonular fibers are weak or disrupted. CTRs help maintain capsular bag shape and stability during phacoemulsification, reducing the risk of capsular collapse, vitreous loss, or lens fragment displacement. They are particularly valuable in cases of pseudoexfoliation, trauma, or congenital zonular weakness. Modified CTRs with fixation elements can provide additional support in cases of severe zonular deficiency.
Usage
Usage note: Commonly abbreviated as CTR in surgical notes. Use lowercase when not beginning a sentence.
In Context
- "A capsular tension ring was inserted to stabilize the bag before IOL implantation." — Operative report
- "The CTR maintained excellent capsular bag configuration throughout the procedure." — Surgical note