Image-guided system streamlines cataract surgery planning

Reviewed by Stephen G. Slade, MD

Take-home message: A new image-guided system streamlines surgical planning for patients undergoing cataract surgery with implantation of a single-piece aspheric IOL or a multifocal IOL.

Houston-Using a new image-guided system (Verion Image Guided System, Alcon Surgical) to plan cataract surgeries with implantation of a single-piece aspheric or multifocal IOL resulted in low residual refractive cylinder and good accuracy to target and refractive outcomes. 

More Cataract: Premium cataract surgery-correcting complications and side effects

These initial results indicate the image-guided system is a valuable addition to the cataract surgery toolkit.

Stephen G. Slade, MD, and Kerry Solomon, MD, evaluated the system in an open-label, prospective, non-randomized, multicenter study that included 188 eyes.

All patients underwent femtosecond laser (LenSx)-assisted cataract removal during phacoemulsification. Any preoperative astigmatism was treated with astigmatic keratotomy.

Related: Clinical experience with a mechanical pupil dilator

Eighty-eight patients were implanted with a single-piece aspheric monofocal IOL (SN60WF, Alcon), and 100 patients were implanted with a multifocal IOL (AcrySof IQ ReSTOR IOL, Alcon).

The residual refractive cylinder, postoperative manifest refractive spherical equivalent (MRSE) accuracy to target, and the best-corrected distance visual acuity (BCDVA) (exploratory efficacy results) were recorded at three months postoperatively, according to Dr. Slade, private practice, Houston.

Recent in Cataract News: How Big Data is changing the game in cataract surgery

The primary study objection was evaluation of the clinical results as measured by the percentage of the study population with 0.5 D or less of residual refractive cylinder three months postoperatively.

The secondary objectives were assessment of the outcome of the manifest refraction spherical equivalent (MRSE) compared with the targeted outcome of 0.5 D or less and a comparison of the keratometry readings, mean corneal curvature, and magnitude of astigmatism and description of the axis measured preoperatively.

Outcomes

Primary, secondary outcomes

At the 3-month evaluation, 62.1% and 82.8% of patients with the monofocal IOL implanted had a residual refractive cylinder of 0.50 D or less and 0.75 D or less, respectively.

Of patients with the multifocal IOL implanted, 71% and 88% had a residual refractive cylinder of 0.50 D or less and 0.75 D or less, respectively.

Recent: Adjustable intraocular lenses after cataract surgery

In comparison, Dr. Slade said the results published by surgeons who manually use an advanced IOL power formula, calculate the surgically induced astigmatism, and perform meticulous ink-marking showed that 53.3% of a toric population achieved 0.50 D or less of residual refractive cylinder (Holland et al. Ophthalmology. 2010;117:2104-2111).

Recent: Novel device reliably measures iridocorneal angles

Regarding the secondary outcomes in the monofocal IOL group, 77% had a MRSE of 0.50 D or less and 97.7% were within 0.75 D or less accuracy.

In the multifocal IOL group, the results indicated that 82% had a MRSE of 0.50 D or less and 94% were within 0.75 D or less accuracy.

Exploratory efficacy outcomes

At the 3-month evaluation of the monofocal IOL group, 62.1%, 86.2%, and 98.9%, respectively, had best-corrected distance visual acuity of 20/20 or better, 20/25 or better, and 20/30 or better.

In the multifocal IOL group, the percentages were 62%, 92%, and 98% for the respective visual acuity levels.

More Cataract: How patient movement can dangerously interfere with FLACS

Investigators concluded that the system is a valuable addition to surgical planning.

Dr. Slade concluded that study results showed patients had low residual refractive cylinder and good accuracy to target and refractive outcomes when using the image-guided system for surgical planning on patients with different IOL platforms.

Stephen G. Slade, MD

E: sgs@visiontexas.com

This article was adapted from Dr. Slade’s presentation at the 2015 meeting of the American Society of Cataract and Refractive Surgery. Dr. Slade is a consultant for Alcon Laboratories.