---
title: What is capsular tension ring?
description: "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…"
url: "https://bluefinvision.com/knowledge-base/topics/treatments-procedures/what-is-capsular-tension-ring/"
updated: "2025-12-12"
category: "Treatments & Procedures"
---

# What is capsular tension ring?

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