Cataract/Anterior Segment, Comprehensive Ophthalmology, Refractive Mgmt/Intervention
Stephen G. Slade, MD, is among the first to perform femtosecond laser cataract surgery in the United States. Three companies are currently developing these lasers: LenSx Laser (Aliso Viejo, Calif.), LensAR (Winter Park, Fla.) and Optimedica (Santa Clara, Calif.). But at this time only LenSx lasers are FDA-approved to create the anterior capsulotomy and corneal incision, as well as for phacofragmentation. Dr. Slade says this new technology promises to deliver safer, more efficient and more accurate surgery; and may represent the next evolution in cataract refractive surgery.
In February I had the distinct privilege to perform the first femtosecond laser cataract surgeries in the United States at my ambulatory surgery center in Houston, Texas using the LenSx Laser (LenSx Lasers, Inc., Aliso Viejo, CA). From what I've learned, I believe these surgeries represent the beginning of the next evolution in refractive cataract surgery.
The LenSx Laser received FDA clearance for anterior capsulotomies in August 2009, followed by clearance for corneal incisions in December 2009, and for phacofragmentation in April 2010.
In the first eight cases in which I used the laser to create the anterior capsulotomy and corneal incision, surgical outcomes were even better than expected. All patients could see 20/25 or better BCVA on postoperative day one. All capsulotomies were perfectly centered and achieved a diametric accuracy of ± 0.25 mm. The laser effectively created precise, self-sealing corneal incisions. After cataract removal using phacoemulsification, a premium IOL was implanted. Anecdotally, my partner and I independently felt that the corneas on day one were exceptionally clear, perhaps due to less intraocular maneuvering and manipulation of the corneal tissue.
Initial clinical evaluation of the LenSx Laser began in 2008 with Professor Zoltan Nagy, MD, of Semmelweis University in Budapest, Hungary1,2,3. Dr. Nagy has successfully performed more than 500 surgeries with the LenSx Laser, including the first image-guided refractive cataract surgeries in December 2009. In these surgeries, the corneal incisions, capsulotomies and lens fragmentation were optimally designed using the laser's integrated OCT device4.
View video of Dr. Slade performing one of his first eight cases
The Patient's Perspective
The overwhelmingly positive response from patients was as impressive as the laser's performance. Then again, patients have always thought that cataract surgery was performed using a laser, which may have helped overcome any concerns they had about being the first U.S. patients to undergo surgery with this new technology.
How patients perceive a particular procedure is vital to how well it is accepted. I learned this with LASIK and femtosecond laser flaps. LASIK results were never proven to be significantly better than PRK, but patients recognized the benefits of quicker recovery and a laser flap compared to a flap created by a metal keratome. Femtosecond laser refractive cataract surgery is much the same. While most of us are proud of how well we can make an incision with a blade or diamond knife and open a capsule with a bent needle, patients will perceive such steps done with a laser as more precise. I believe their perceptions will drive them to this technology. All of us have been in the position where we have counseled a patient for our own "first procedure." I was counseling these patients to be the first in the United States to have part of their surgery done with a new laser - the only one approved for use in the US. Yet I was amazed to see how quickly they agreed.
The Surgeon's Perspective
There are many potential benefits that may arise with femtosecond laser cataract technology. With a more reproducible operation, we now have an opportunity to learn about the clinical significance of precisely sized and positioned incisions and capsulotomies. For how can we study these steps if we cannot provide a reproducible benchmark? The ability of the laser to make precise, reproducible corneal incisions and capsulotomies will allow surgeons to optimize lens position, more effectively manage pre-existing astigmatism, and possibly even reduce induced astigmatism.
With such reproducible incisions, I believe the laser will help us improve refractive results. We may learn that we can improve and quantify the effective lens position of an IOL by controlling the size, centration and shape of a laser capsulorhexis. In the future, ophthalmologists should be able to make corneal astigmatic incisions with the laser to address pre-existing cylinder and further improve postoperative refractive results. It is time we provided better UCVA to our cataract patients. Results from current IOL studies pale compared to LASIK results (40 percent seeing at 20/40 compared to 90 percent with LASIK). Good luck trying to get an IOL approved as a LASIK study through the FDA.
I suspect that patients will further benefit from femtosecond laser technology as we anticipate a lower complication rate than currently associated with standard cataract surgery. Current vitreous loss rates range from 2 to 6 percent of all cases. Wouldn't reducing phaco time with the laser and avoiding a manual capsulorhexis reduce the rate of vitreous loss?
In summary, my initial experience with "bladeless laser cataract surgery" has been extremely positive. In my years as a refractive and cataract surgeon, I have had the good fortune to be deeply involved with the introduction of a number of new technologies including LASIK, accommodating IOLs and the femtosecond laser for corneal flaps. These technologies have profoundly changed what we are able to offer our patients. Yet what have we done in cataract surgery? Think of it. If an ophthalmologist from the 1980s appeared by time travel in our offices today, the phaco machine would be the only recognizable tool. All of the diagnostics, drugs, excimers, yags, etc. would be new. With this laser, I believe we will soon have a cataract surgery technology that may enhance the performance of premium IOLs. It is time to change the way we do cataract surgery. We are facing a wave of baby boomers, all with extremely high expectations for their cataract surgery outcome. Surely this technology is in the right place at the right time.
- Nagy Z. Use of femtosecond laser system in cataract surgery. Paper presented at: XXVII Congress of the ESCRS; September 15, 2009; Barcelona, Spain.
- Nagy Z. Intraocular femtosecond laser applications in cataract surgery. Cataract & Refractive Surgery Today Europe. 2009;4(8):29-30.
- Nagy Z,Takacs A, Filkorn T, Sarayba M. Initial clinical evaluation of an intraocular femtosecond laser in cataract surgery. J Refract Surg.2009;25(12):1053-1060.
- Nagy Z. Application of an integrated OCT in novel femtosecond laser cataract surgery; The 14th Winter ESCRS Meeting; February 14, 2010, Budapest,Hungary.
The author discloses that he serves as the medical director for LenSx Lasers Inc., and is an advisor/consultant to Alcon Laboratories, Inc., Bausch & Lomb, IntraLase Corp. and STAAR Surgical Company.