Lara C. Pullen, PhD

May 03, 2012

May 3, 2012 (Chicago, Illinois) — Four- and 5-year data from second-eye implantation of the AcrySof Cachet phakic lens reveal stable and predictable refractive outcomes with excellent visual acuity.

Two studies of the phakic intraocular lens (IOL) were presented here at the American Society of Cataract and Refractive Surgery 2012 Symposium on Cataract, IOL and Refractive Surgery.

Thaddeus T. Demong, MD, from the University of Calgary in Alberta, Canada, presented the 4-year interim results from a prospective multicenter 5-year study conducted in Canada.

David Horn, MD, from Vision for Life in Nashville, Tennessee, presented the results of a phase 2 clinical trial conducted in the United States.

Both studies had the same design and yielded similar results. The "visual outcome and stability are excellent" with these lenses, Dr. Demong told Medscape Medical News. Dr. Horn agreed, adding that the lenses "allow people to see better."

The purpose of the Canadian study was to assess refractive and visual acuity outcomes 4 years after implantation of the investigational phakic lens. The lens is used to correct moderate to high myopia.

The phakic lens is made of a single piece of foldable hydrophobic acrylic IOL material. It is an angle-supported anterior chamber lens. The diopter range is from –6.0 to –16.5. The lenses were inserted using the Monarch II IOL delivery system.

The Canadian study was a single-group clinical study that involved 120 participants, 105 of whom received bilateral lenses. First-eye results had been presented previously, so this report included only second-eye results.

The efficacy, safety, and quality-of-life results were presented by Dr. Demong; safety outcomes were presented elsewhere.

He reported that mean spherical equivalent was stable during the 4 postoperative years. Refraction was predictable at 4 years, with 74% of eyes within ±0.5 diopters of the target and 94.5% of eyes within ±1.0 diopters of the target.

The mean corrected distance visual acuity (CDVA) was –0.03 ± 0.13 logarithm of the minimum angle of resolution (logMAR) preoperatively (n = 105) and –0.14 ± 0.11 logMAR 4 years after implantation (n = 73). At 4 years, all eyes had a CDVA of 20/32 or better.

Preoperatively, the uncorrected distance visual acuity (UDVA) was too poor to measure for most eyes. At 4 years, the mean UDVA was –0.04 ± 0.16 logMAR (n = 73). This is slightly better than preoperative CDVA. The UDVA distribution revealed that 75.3% of patients were 20/20 or better, 98.6% of patients were 20/25 or better, and 97.3% of patients were 20/40 or better.

Dr. Horn reported a CDVA of 20/25 or better in 100% of patients in the American trial.

In the same session, Beatrice Cochener, MD, from the University of Brest in France, presented safety data from global trials of the phakic lens. She described 5 years of data indicating that the phakic lens is safe, but she explained that "we need 10 years to assume that it is safe."

Howard Gimbel, MD, from the University of Calgary, attended the session and spoke with Medscape Medical News about the research: "Be on guard. So far it looks okay, but from previous experience...the surgeons and the patients need to go into this with their guard up."

Both studies were sponsored by Alcon. Dr. Demong reports being a member of an Alcon advisory board. Dr. Horn reports being a consultant and lecturer for Alcon. Dr. Cochener reports being funded by Alcon. Dr. Gimbel has disclosed no relevant financial relationships.

American Society of Cataract and Refractive Surgery (ASCRS) 2012 Symposium on Cataract, IOL and Refractive Surgery. Presented April 22, 2012.