Influence Of An Intraocular Open Capsule Device On Refractive Predictability In Cataract Surgery

The intraocular open capsule device (IOCD), implanted into the capsular bag after the crystalline lens removal and before the IOL implantation, has the potential to prevent up to 80% of the PCO. The current study aimed to assess the influence of the CleaRing IOCD on the refractive predictability in cataract surgery. 

A prospective controlled preliminary study in the Edith Wolfson Medical Center, Holon, Israel.

Ten eyes of 10 patients underwent cataract surgery and IOL implantation after implantation of the IOCD, all performed by the same surgeon. If both eyes of same patient had surgery, only the first eye was included. Inclusion criteria: age 50-80 years, visually significant cataract, good visual acuity (VA) potential following surgery, ACD ≥ 2.5mm, corneal astigmatism ≤ 2D, AL 22-26mm, pupil diameter ≥ 6mm, average keratometry 42-46D. All patients completed 12 months follow up which included: refraction, uncorrected distance VA (UDVA), corrected-distance VA (CDVA), optical biometry, slit-lamp biomicroscopy and ultrasound biomicroscopy (UBM). IOL power was calculated using Barrett Universal II formula. Refractive predictability was calculated.

All surgeries were uneventful. There were no postoperative complications. All IOLs were centered in the device and bag. The manifest refractive cylinders 12 months postoperatively were compatible with corneal astigmatism in all cases. The average UDVA was 0.17 ± 0.13 and 0.15 ± 0.11 logMAR, at 1 and 12 months postoperative, respectively with average CDVA of 0.04 ± 0.10 and 0.04 ± 0.06 logMAR, respectively. The average prediction error was +0.28 ± 0.32 D and +0.33 ± 0.24 D at postoperative months 1 and 12 follow-up, correspondingly. All devices maintained an open capsule and showed significant prevention of posterior capsule opacification through the entire follow-up period.

The IOCD implantation results in slight hyperopic shift due to posterior location of the IOL. The refraction was stable with no significant change between postoperative months 1 and 12. The standard deviation of the prediction error is excellent and low as 0.24 D at 12-month follow-up, which implies excellent refractive accuracy and predictability using the IOCD. No IOL tilt was found.