A capsular tension ring (CTR) is a flexible ring implanted into the capsular bag during cataract surgery to stabilise it when zonules are weak or broken. It helps maintain a round, centred capsule for intraocular lens placement.
Function
The ring expands the capsule circumference and redistributes support around areas of zonular loss. This reduces the risk of capsular collapse, decentration, or later dislocation of the IOL.
- Inserted after capsulorhexis and before or after lens removal, depending on the case
- Variants with fixation eyelets can be sutured to the sclera for additional support
- Useful in pseudoexfoliation, trauma, and some congenital lens conditions
- Requires appropriate sizing and careful insertion to avoid capsule damage
Clinical Considerations
CTR use improves surgical control but does not eliminate all risk in unstable capsules. Long‑term follow‑up is still required.
- Future IOL exchange or manipulation can be more complex with a ring in place
- Imaging may help assess ring and lens position over time
- Patients should be counselled about the increased complexity of their surgery
- CTR technology has significantly expanded options for preserving the capsular bag
