Femtosecond laser cleared for lens fragmentation

Aliso Viejo, CA-LenSx Lasers Inc. announced April 27 it received FDA clearance of its proprietary femtosecond laser technology (LenSx) for use in performing phacofragmentation during cataract surgery.

The decision from the regulatory agency represents the third cleared clinical indication granted for use of the femtosecond laser during cataract surgery. In August 2009, LenSx received initial clearance for performing anterior capsulotomy. Clearance for creating the corneal incisions was achieved in December 2009.

In February 2010, Stephen G. Slade, MD, performed the first cataract surgery procedure in the United States using the LenSx femtosecond laser. He told Ophthalmology Times that he is impressed by the company's accomplishments in achieving three indications within such a short period, enthusiastic about his experience with the laser, and excited about the future promise of this technology for further enhancing the safety, efficacy, and efficiency of cataract surgery.

"The ability to use this device for lens fragmentation has implications for increasing surgical safety and improving visual recovery," he added. "Not only are there data to show that the laser-assisted lens fragmentation step reduces ultrasound use relative to a manual technique, but by enabling nucleus removal, I believe laser lens fragmentation will also reduce the occurrence of capsule rupture."

The data Dr. Slade referred to are from an ex vivo study performed by Zoltan Nagy, MD, clinical professor of ophthalmology, Semmelweis University, Budapest, Hungary, and Melvin Sarayba, MD, LenSx. They were reported by Dr. Nagy at the annual meeting of the American Society of Cataract and Refractive Surgery in Boston in April and in a recently published paper [J Refract Surg. 2009;25:1053-1060].

Dr. Nagy has been collaborating with LenSx since 2008 to develop the femtosecond laser for cataract surgery, and the FDA approvals for the platform are based on data he has collected in clinical trials.

For the ex vivo study, a total of 24 porcine eyes were divided into two groups to undergo laser nuclear segmentation or a traditional manual divide-and-conquer technique. Eyes from pigs at least 5 years old were purposely chosen for the investigation because the lens is consistently dense in animals of that age so that ultrasound power would be needed for complete nucleus removal. For the divide-and-conquer group, the phaco tip was used to create grooves in perpendicular meridians, and then the lens was divided into quadrants. In the laser procedure, the lens was divided into four equal sections by creating two intersecting ellipsoidal planes. The ellipsoids measured 6 mm in length; the cuts were made beginning at 1,000 µm above the posterior capsule and ascended to <1,000 µm below the anterior capsule. Settings for energy and spot separation were based on previous optimization studies.