Seeking the Solution for Accommodating IOL Success

New IOL harnesses ciliary muscle movement. Cheryl Guttman Krader reports from ASCRS in Las Vegas, USA

Anovel accommodating IOL (AIOL, Opira, ForSight VISION6) proved safe and stable, providing continuous “monofocal quality” vision across the functional near range in a recent clinical study, according to Ayman Naseri MD.

Dr Naseri presented data from a study of 29 patients who were followed for two years after bilateral cataract surgery with implantation of a monofocal IOL in one eye and the Opira AIOL in the fellow eye. The surgeries were performed without any attempt to correct astigmatism. For distance correction, mean Snellen intermediate and near visual acuity in the Opira AIOL eyes was approximately 20/20 and 20/25, respectively. This was superior to the outcomes in the monofocal IOL eyes.

Consistent with the visual acuity results, the monocular defocus curve from testing performed at two years showed the Opira AIOL had an extended range of focus across a large dioptric range, Dr Naseri said.

He also shared the first data report from the follow-up of up to two years for nine patients who had bilateral Opira AIOL implantation. He noted refractive outcome accuracy improved in this cohort because the surgeries occurred after refining the AIOL’s A-constant. Without correction, mean binocular visual acuity at two years was better than 20/20 at distance, 20/20 at intermediate, and approximately 20/25 at near. The distancecorrected outcomes were even better, and data demonstrating achieved objective accommodation will be presented in the future, he said.

To highlight the performance of the Opira AIOL and show it addresses the functional limitations of existing presbyopia-correcting IOLs, Dr Naseri presented a graph showing the binocular defocus curves of the Opira AIOL and several commercially available multifocal presbyopia-correcting IOLs.

“The defocus curve for the Opira AIOL is based on just nine patients, but in many ways, our lens is demonstrating exactly what we are looking for in the holy grail search for an accommodating IOL—true accommodation throughout a range of visual function. We are very excited about continuing its development.”

DESIGN RATIONALE Dr Naseri proposed dependence on the capsular bag to mediate accommodative effort has been a limiting factor hampering successful AIOL development. He explained that interpatient variability in capsular bag elasticity and volume—combined with fibrosisinduced capsular bag changes that occur over time—creates an unpredictable environment leading to unpredictable outcomes.

“We believe the right approach is to directly harness ciliary muscle movement to drive shape change in an accommodating IOL,” Dr Naseri explained.

The Opira AIOL is a ciliary muscle-driven, capsule-fixated, dynamic shape-changing device. Its accommodative mechanism is based on direct ciliary body engagement without zonular support or capsular bag intermediaries. Made of silicone, the Opira AIOL is injected through a clear corneal incision and haptic-fixated within the capsulorhexis. It has a dynamic anterior surface and a static posterior lens available for toric correction and postoperative adjustment.

“The Opira accommodating IOL spans from ciliary muscle to ciliary muscle, and when the ciliary muscle moves in a centripetal fashion with accommodative effort, the Opira AIOL changes shape on its anterior surface, similar to what happens in the young phakic eye,” Dr Naseri explained.

ADDITIONAL DETAILS The current iteration of the Opira AIOL requires insertion through a 3.9 mm incision, but the company is targeting to reduce the minimum incision size to 3.0 mm. The lens is being made to fit eyes with varying dimensions, and lens size is chosen based on preoperative measurements taken with ultrasound biomicroscopy.

Proper sizing is important for the performance of the Opira AIOL, Dr Naseri emphasised. Proper sizing of the capsulorhexis is also important regarding IOL implantation. So far, surgeons have achieved successful outcomes using either a manual technique or femtosecond laser for the capsulorhexis.

“It may be an issue if the capsulorhexis size is radically off target, but we think capsulorhexis creation will be relatively straightforward,” Dr Naseri said.

Asked about the potential for uveitis-glaucoma-hyphaema syndrome with the accommodating IOL, Dr Nasir acknowledged this complication is a potential concern with any lens that sits in between the iris and the anterior capsule. Unlike sulcus-based lenses that are positionally fixated and stabilised by ciliary/sulcus structures, the Opira AIOL is capsule-fixated, which mitigates the risk of IOL movement and tissue erosion. Its safety profile is excellent for the patients with two years of follow-up, but additional data from longer follow-up in more patients are needed to fully answer the question, and he suggested specific lens design features should mitigate the risk.

“I think many clinicians would agree the sulcus is a pretty safe place to put a lens that doesn’t move and has no sharp edges. The Opira AIOL has a very smooth surface, and it is very stable in the eye,” Dr Naseri said.

He reported posterior capsule opacification is common because the Opira AIOL does not have much peripheral intracapsular hardware. Many patients have undergone Nd:YAG capsulotomy without any adverse effect on their functional results.

Ayman Naseri MD is president and chief medical officer of ForeSight VISION6; Professor of Ophthalmology, University of California, San Francisco, USA anaseri@forsightv6.com