Preliminary results of the ESCRS Femtosecond Laser-Assisted Cataract Surgery (FLACS) study show laser cataract surgery is as good as routine phacoemulsification, but does not currently outperform it, said Peter Barry, FRCS FRCOphth, during the 2014 European Society of Cataract & Refractive Surgeons meeting in London.
Funded entirely by ESCRs, this is the first time FLACS outcomes are compared with outcomes in matched patients undergoing routine phacoemulsification in terms of the major benchmarks of quality: visual acuity, surgically induced astigmatism, complications, and biometric errors.
“At the moment, I think we can conclude that in its current state of infancy, femto cataract surgery is as good as phaco, but currently does not, by these measures, outperform it,” Dr. Barry said
Although ongoing, the study currently includes 2,022 patients from 16 centers in 10 countries who underwent FLACS between December 2013 and August 6, 2014, and 4,962 patients randomly selected from a pragmatic sampling of 100,000 patients enrolled in the EUREQUO study, a database that includes approximately 1.5 million patients who have undergoing cataract surgery.
Measurements not included in the study, because they had no comparison in the EUREQUO database, were circularity of capsulorrhexis, centration of capsulorrhexis, femtosecond platform, endothelial cell loss, effective lens position or higher-order aberrations.
Although the groups had a similar rate of intraoperative complications at 0.5% or less, more postoperative complications occurred in the FLACS group, Dr. Barry reported, with 3.2% of FLACS patients and 1.8% of routine phaco patients reporting a complication after surgery.
Also of note was the difference in premium IOL use between the groups, he said. In the FLACS group, 39.6% of patients received a multifocal IOL and 6.5% received a toric IOL, compared with 0.3% and 0.2%, respectively, in the phaco group. This led to more patients with slightly better “supervision” in the FLACS group, he said.
(listen to more of Dr. Barry's presentation)
Other data presented in London suggest that using the femtosecond laser to create corneal incisions may injure the endothelium, offsetting the benefit of putting less energy in the eye with femtosecond-assisted surgery.
Dr. Brendan Vote, clinical associate professor at the University of Tasmania, presented data from comparative cohort studies showing more endothelial cell loss and a decrease in corneal thickness in the early postoperative period between standard phaco and femto-assisted surgery. However, at six months the difference disappeared. Additionally, Dr. Vote said that a sub-analysis of his data show a possible safety issue in the posterior segment. He found a trend toward more cystoid macular edema with femto-assisted surgery, though it was not statistically significant (0.2% vs. 0.8%), and patients were successfully treated with NSAIDs.
Other speakers here presented data showing femtosecond cataract surgery to be especially useful in challenging cases: mature cataract, white cataract, zonular weakness, pediatric cataract and posterior polar cataract.
H. Burkhard Dick, MD, PhD, professor and chair of the Ruhr University Eye Hospital in Bochum, Germany, presented his experience using the femtosecond laser to create a posterior capsulotomy. Performed immediately after the primary surgery is complete (with the wound closed and the IOL in place), the femtosecond laser posterior capsulotomy has three basic steps: the laser is redocked to the eye, and the eye is then rescanned and reshot with the laser. He believes this procedure could potentially eliminate PCO.
While early data shows no significant visual benefit from the perfection of the automated femtosecond laser-assisted surgery, new IOLs are taking advantage of the perfectly created capsulorhexis.
Rudger Hanneken, MD, shared his experience utilizing the Lentis LaserLens (Oculentis), designed specifically for femtosecond laser-assisted cataract surgery to provide higher predictability, refractive precision and stability.
“With the new lens, the concept is to be implanted in the capsular bag then locked by the edges of the capsulotomy. The precise execution with predictable size and position of capsulotomy is necessary, but only possible with the laser’s assistance,” Hanneken said. “This locked position may minimize decentration, tilt and rotation. Higher predictability, refractive precision and stability is expected.”
While some of the early enthusiasm for the benefits of femtosecond cataract surgery was dampened at this year’s meeting, most speakers here said they believe the technology will improve and that it continues to represent the future of modern, automated cataract surgery.