A perfect capsulotomy—round, centered, flawless. A fragmented nucleus—chopped and ready for aspiration without ultrasound. Pristine corneal incisions—predictable, accurate, precise.
These are the attributes of laser-assisted cataract surgery. The interest, excitement, and controversy surrounding this innovative technology demonstrate that laser-assisted cataract surgery has caught the imagination of surgeons worldwide.
CLINICAL FOUNDATION
Today, only a small percentage of surgeons are using this technology, which is still in its infancy; however, femtosecond lasers for cataract surgery loom larger than life thanks to great marketing. The images are relentless, especially the LenSx (Alcon) dominoes. Yet, we must strive to remain scientific and objective in our assessments of safety and effectiveness of laser-assisted cataract surgery.
Safety
Reduced endothelial cell loss? Check. Reduced corneal edema? Check. Reduced macular edema? Check.
Effectiveness
Reduced postoperative mean refractive spherical equivalent absolute error? Check. Reduced IOL tilt? Check. Reduced postoperative astigmatism? Check. The magnitude of the significance of these improvements may not feel large enough, but this is similar to that of someone playing the stock market: When growth does not always beat analysts’ expectations, prices often fall as a result of psychology rather than fundamentals.
Who set the expectations for laser-assisted cataract surgery? We did, and we did so arbitrarily. If expectations are too high, improvements may feel disappointing. But, as improvements, they are by definition better than what went before.
“Incremental improvements,” said I. Howard Fine, MD, of Eugene, Oregon (personal communication). Incremental improvements have been the story of phacoemulsification from the beginning—a long line of innovations and improvements including the introductions of the capsulorrhexis, clear corneal incisions, topical anesthesia, phaco techniques such as phaco chop and biaxial, microincisions, intraoperative aberrometry, and on-screen guidance. What a long, great trip it’s been.
Now comes laser. Demonstrated clinical improvements have been shown in the work of Harvey S. Uy, MD, in Makati City, Philippines, with the commercial version of the Lensar Laser System (Lensar, Inc.). 1 Additionally, research on the liquid optics interface, conducted by Jonathan Talamo, MD, of Waltham, Massachusetts, was highlighted on the cover of the February 2013 issue of the Journal of Cataract and Refractive Surgery. 2 His article in that issue reminded me of what I liked about Lensar from the beginning of my involvement with the company 3.5 years ago: The liquid interface just makes sense. No corneal compression, no endothelial wrinkles, and, therefore, no skip areas in the caspsulotomy. After all, anterior radial tears are the most common complication of capsulotomy. Additionally, I have used the Lensar to cut through the worst nuclear sclerosis. It transformed the case from dire necessity to fun and games. The laser can also create corneal and relaxing incisions, although the latter function is still undergoing development. We aim to demonstrate reduction of preexisting corneal astigmatism with laser relaxing incisions in an ongoing study.
MANAGEMENT CONSIDERATIONS
The affordability of femtosecond laser technology for cataract surgery depends on one’s expectations for return on investment. You may miss, hit, or exceed expectations this month, but the long-term prospect looks far different. I believe the lens surgery of the future involves a femtosecond laser.
Timing is everything, and your specific market may not be ready for this innovation. You can always let somebody else do it first, but be the No. 2. The second practice to enter the market often outperforms the first, and there is no shame in that. Do not get caught up in playing a game of chicken—a game where deception is everything—by waiting to see who will draw first. There may be some shame in playing that game.
In business, as in life, follow your heart. I like Lensar’s mobility and design. The interface’s suction ring and docking device have been good but sometimes finicky. This is being improved. I have yet to see a system that does not produce subconjunctival hemorrhage. To me, this is the only real clinical disadvantage of femtosecond surgery. I miss my patients’ white, quiet eyes.
My friends with femtosecond lasers are generally happy. They would all like to see certain specific improvements, and everyone has ideas for how the laser systems can be improved—another sign the technology is in its infancy.
Service, support, and maintenance of these units vary from country to country. Check with local sales representatives to see what can be done in your market. As always, the service contract is of major importance. A lost day in the operating room really hurts.
CHALLENGES FOR THE FUTURE
How can we incorporate ocular registration and guidance into laser-assisted cataract surgery? Due to the effect of the suction ring, the optics of the eye cannot be measured as the cuts are being made. Postoperative titration, if proven, could be one answer, although this does not quite meet expectations for single-session surgery.
Unless one returns to the laser after cataract extraction, intraoperative wavefront aberrometry is playing catch-up, as the incisional work is done before the first measurements are taken. This is the only surgical disadvantage of laser-assisted cataract surgery.
Premium surgery demands premium technology. They work hand in hand to create great vision without glasses, satisfied patients, and satisfied surgeons.
Mark Packer, MD, FACS, CPI, is a Clinical Associate Professor at the Casey Eye Institute, Department of Ophthalmology, Oregon Health & Science University, and President of Mark Packer MD Consulting. Dr. Packer states that he is a consultant to Lensar, Abbott Medical Optics Inc., and Bausch + Lomb. He may be reached at e-mail: mark@markpackerconsulting.com.
- Uy H, Packer M. Changes in endothelial cell density in large cohort of patients having laser refractive cataract surgery. Paper presented at: the American Society of Cataract and Refractive Surgery annual meeting; Chicago; April 20-24, 2012.
- Talamo JH, Gooding P, Angeley D, et al. Optical patient interface in femtosecond laser-assisted cataract surgery: Contact corneal applanation versus liquid immersion. J Cataract Refract Surg. 2013;39(4):501-510.
