Today’s laser cataract surgery is outperforming the early days of phacoemulsification and may outperform current phacoemulsification technology in the next few years, explained Yassine Daoud, MD, in a dialogue about the technology.
Take-home message: Today’s laser cataract surgery is outperforming the early days of phacoemulsification and may outperform current phacoemulsification technology in the next few years, explained Yassine Daoud, MD, in a dialogue about the technology.
By Stephanie Skernivitz; Reviewed by Yassine Daoud, MD
Baltimore-Any present-day discussion of femtosecond laser-assisted cataract surgery over conventional phacoemulsification may prompt several relevant questions.
“Is it safer? Is it better? Is it cost-effective?” These three questions are top of mind for Yassine Daoud, MD, assistant professor of ophthalmology, Department of Cornea, Cataract and Refractive Surgery, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore.
Dr. Daoud provided a brief review of the literature to question whether the procedure really is safer.
“The safety of cataract surgery is pretty impressive as far as medicine goes, but it isn’t perfect,” he said.
He cited a number of examples to highlight the procedure’s safety. When addressing the safety of femtosecond laser-assisted cataract surgery compared with conventional phacoemulsification, capsule issues come into play.
Dr. Daoud discussed multiple epidemiological studies that pertain to the rate of various complications, such as anterior capsular tear, which, in regular phacoemulsification, is 2.8%. In femtosecond laser, this can be as high as 4%. With lens dislocation, it is 2% in the femtosecond group, higher than what is normally seen.
“It’s a learning curve,” he said. “Once you master the learning curve, the complication rate becomes lower than conventional phaco.”
For example, one study by Roberts et al. (published in 2013 in Ophthalmology) found that the surgical outcomes and safety of femtosecond laser-assisted cataract surgery improved significantly with greater surgeon experience.
From a historical perspective, in 1997, there was posterior capsular tear in 13.3% of eyes; iris trauma in 4%; and vitreous/dropped lens in 1% in phacoemulsification cases. The total percentage of eyes with complications was 21.7%. Surgery involved 2.6 minutes of ultrasound, and total surgical time was about 18 minutes in experienced hands, according to Dr. Daoud.
“Today’s femtosecond is actually outperforming phaco in its earlier days,” he said. “Is it going to bear out that femtosecond becomes the surgery of the future?”
So, is femtosecond laser safer? For one, “there is growing evidence that using femtosecond laser leads to a decrease in use of ultrasound energy,” Dr. Daoud said.
He cited a report by H. Burkhard Dick, MD, PhD, of Germany, who stated that with cataracts of grade 2, grade 3, and grade 4 (LOCS III classification), he has reduced ultrasound use by 100%, 98%, and 97% respectively. According to Dr. Daoud, in 95% of Dr. Dick’s surgeries he is not using any ultrasound.
This raises the question of whether physicians will move to “ultrasound-less” cataract surgery.
“Are we going to be removing the whole ultrasonic technology altogether?” Dr. Daoud asked. “That remains to be seen. Though it may be great that I’m using less ultrasound, how is that affecting the health of the eye?”
There is a concern with endothelial cell health and density after cataract surgery. Indeed, corneal edema after cataract surgery was a leading cause for subsequent corneal transplant. How would reduced use of ultrasound impact the health of the corneal endothelium, which is where the stress of the ultrasound is typically.
Regarding endothelial cell density, Dr. Daoud noted there has been no difference on the endothelial cell health as a result of femtosecond laser-assisted cataract surgery compared with conventional phacoemulsification.
“Based on the literature so far, somehow the cornea is a little more resilient to the new ultrasound modulations we are using,” he said.
Other pertinent questions raised by Dr. Daoud include: “Is femtosecond laser-assisted cataract surgery better? Is it better for me as a physician? Is it enabling my surgeries to be more successful? Are my patients happier? Are my patients performing better? Is it cost effective?”
He noted the unfortunate combination of aging baby boomers and increasing health-care costs. Americans already pay more than others in the world per gross-domestic-product percentage of health care, according to Dr. Daoud.
“Is our system going to be able to spend more money on more technology, as well as future directions?” he asked.
Dr. Daoud praised the nationalized health-care systems of Europe and their European Registry of Quality Outcomes for Cataract and Refractive Surgery, a database where many cataract surgeons report data from patients and surgical outcomes. To date, more than 1.3 million surgical cases are housed in the system from which researchers can extract data.
Findings extracted from the database were recently reported by the European Society of Cataract and Refractive Surgeons group and involving Peter Barry, FRCS, FRCOphth. They compared 2,000-plus femtosecond laser cases from about 16 centers across Europe with 5,000 phacoemulsification surgeries. The quality outcome measures are mainly visual acuity, biometric prediction error, surgically induced astigmatism, vitreous loss, and a drop in nucleus.
“In the two groups-femtosecond laser versus conventional phacoemulsification-the outcomes are essentially the same,” Dr. Daoud said.
The next question may be whether the procedure is any better than what is currently out there, Dr. Daoud posited.
“By ‘better,’ I mean, my patient asks: ‘Do I need the glasses? Do I need them far away? Close up? When do I need them? What is my best-corrected visual acuity [BCVA]? What is my uncorrected visual acuity?’” he explained.
To date, what can be measured with femtosecond laser versus phacoemulsification are spherical equivalent, cylinder, mean absolute predictive refractive error, uncorrected distance visual acuity, and BCVA.
In each of these, according to Dr. Daoud, there is no noticeable change or any difference between femtosecond laser and phacoemulsification.
The femtosecond cost effectiveness currently is about $92,000 Australian dollars per quality adjusted life year as reported by an Australian group. In a best-case scenario, this would be about $20,000 dollars. In contrast, conventional phacoemulsification is about one-fifth of that cost, or $4,378, Dr. Daoud noted.
Dr. Daoud and colleagues are currently working on a study and recruitment for it is under way. His team has a grant to cover the femtosecond laser portion of the procedure. The procedure entails one eye being performed with conventional and one eye with laser.
“We will measure outcomes in a truly prospective, unbiased study,” he said.
Dr. Daoud described a cartoon that stated: “My team has created a very innovative solution, but we are still looking for a problem to go with it.”
“That’s really what’s going to happen in the next 5 to 10 years,” he quipped. “I’m very optimistic. This is the surgery of the future. But I’m not sure it’s ready yet for public dissemination.” â
Yassine Daoud, MD
This article was adapted from Dr. Daoud’s presentation during the 27th annual Current Concepts in Ophthalmology meeting at the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore. Dr. Daoud has no relevant financial interest.