Capsular Rings

Capsular Tension Rings (CTRs) are indicated to stabilize weakened, broken or missing zonules, preventing IOL decentration after capsular shrinkage.

The CTR is a PMMA open-ring device with blunt tipped eyelets at either end. The CTR is designed to be implanted into the capsular bag and left permanently in place. CTRs work by imparting a radial expansile force to the equator of the capsular bag. This force is equalized throughout the entire zonula-capsule apparatus, thereby transfering the tension from intact and normal zonules to those areas of zonular weakness or absence. By increasing overall bag stability, the risk of intraoperative complications is reduced. In addition, the tension imparted to the entire bag with a CTR decreases postoperative capsular contraction (phimosis) and improves IOL centration. CTRs have no effect on the refractive results of cataract surgery. Whether or not a CTR will decrease the rate of late IOL/bag subluxation is still being evaluated and debated. In order to be most effective, the CTR should be larger in diameter than the capsular bag. Ultrasound biomicroscopy has shown that a correctly placed CTR lies between the IOL haptic and the ciliary body with no iris touch and that its position is stable, safe and consistent.

Capsular Tension Rings (CTRs) are indicated to stabilize weakened, broken or missing zonules, preventing IOL decentration after capsular shrinkage.

The CTR is a PMMA open-ring device with blunt tipped eyelets at either end. The CTR is designed to be implanted into the capsular bag and left permanently in place. CTRs work by imparting a radial expansile force to the equator of the capsular bag. This force is equalized throughout the entire zonula-capsule apparatus, thereby transfering the tension from intact and normal zonules to those areas of zonular weakness or absence. By increasing overall bag stability, the risk of intraoperative complications is reduced. In addition, the tension imparted to the entire bag with a CTR decreases postoperative capsular contraction (phimosis) and improves IOL centration. CTRs have no effect on the refractive results of cataract surgery. Whether or not a CTR will decrease the rate of late IOL/bag subluxation is still being evaluated and debated. In order to be most effective, the CTR should be larger in diameter than the capsular bag. Ultrasound biomicroscopy has shown that a correctly placed CTR lies between the IOL haptic and the ciliary body with no iris touch and that its position is stable, safe and consistent.

Cionni Rings For Scleral Fixation are CTRs with additional fixation eyelets to allow the entire ring to be fixated permanently to the sclera with sutures. The suturing eyelets are positioned slightly anterior to the ring, allowing the ring to be placed into the capsular bag while the eyelets remain anterior to the capsule. This configuration allows suturing of the ring to the scleral wall by means of the eyelet without compromising the integrity of the capsular bag. There are different models available to provide more versatility in placement of scleral fixation depending on the extent and area of zonular weakness.

Capsular Segments For Scleral Fixation are created for patients with extensive and/or progressive zonular loss. The partial PMMA ring segment traces a 120° arc with a radius of 4.5 or 5.0 mm and an anteriorly positioned fixation eyelet. Unlike the CTR and MCTR, the CTS can be used in cases where a discontinuous capsulorhexis, an anterior capsule tear or a posterior capsule tear is present, as it does not generate a 360° expansile force. Multiple CTS’ can be used if necessary. The CTS provides support in the area of fixation and should be combined with a CTR or MCTR when circumferential support is required. The CTS may also be used for intraoperative support and removed prior to completion of the surgery.