Cataract
September 2022
by Ellen Stodola
Editorial Co-Director
The Light Adjustable Lens (LAL, RxSight) is still a relatively new IOL technology, offering the ability to adjust the refractive settings of the lens after implantation with “lock-in” treatments. In this article, several physicians discussed their decision to bring it into practice, implementation considerations, and overall impressions.
Source: Nicole Fram, MD
Nicole Fram, MD
Dr. Fram decided to bring the LAL into her practice when she realized she had a more than 20% post-LASIK/PRK patient population needing cataract surgery. Even the best formulas reach a refractive target +/–0.50 D 69–79% of the time, she noted.1–5 “The promise of a technology that we could adjust after surgery to meet the refractive goals was exciting,” she said. “In addition, our primary strategy for independence from glasses in this patient population was mini-monovision, as the EDOFs and multifocals on the market at the time had significant diffractive dysphotopsia.”
Dr. Fram said workflow adjustments to accommodate the LAL were relatively easy. The patients had all appointments scheduled from the start and understood how long they would need to be in the office. It is important to explain upfront that this technology is not for all patients, particularly if they are from out of town or have a low threshold for wait times.
Dr. Fram said she had no reservations about implementation, except that prior to the ActivShield technology, she had one patient develop a central zone and poor vision due to non-compliance with the protective glasses. “Fortunately, the development of ActivShield has decreased this risk, and we have not seen a single case since its implementation.”
It’s important to tell the patient that the strategy for more spectacle independence is blended monovision. “They need to understand the 80/20 rule—80% of what they do on a day-to-day basis will be spectacle-free. However, this is still monovision, and when driving at night or reading a medicine bottle, they may need glasses.” Monovision in the pseudophake is different than monovision with LASIK/PRK or contacts, as their natural crystalline lens may allow for some accommodation. Dr. Fram explains to patients that the LAL technology can more effectively hit targets and customize vision, particularly in the post-corneal refractive surgery population.
Dr. Fram noted there is not currently an IOL that exactly counterbalances the higher order aberrations of the cornea and/or accommodates. “This is the missing advancement in the world of lens replacement,” she said. “This technology may solve the effective lens position issue by providing postoperative adjustment capabilities. However, it does not fully counteract these aberrated corneas to achieve better quality of vision.” She added that the EDOF version will be interesting, if it does not increase the dysphotopsia profile.
Phillip Hoopes Jr., MD
Dr. Hoopes has been using the LAL technology for 8–9 years, from the FDA trial through its launch, giving him a unique perspective. Hoopes Vision has a research center, he said, so it’s able to get involved in a lot of industry research and studies, including the LAL FDA study. Once the product was approved in 2019, his practice began using it.
Dr. Hoopes said the LAL involves a change from the usual mindset. With traditional implant technology, most of the work is done before surgery. You make your measurements, you put the implant in, and you’re stuck with the results. “The Light Adjustable Lens is a crossover into the idea of refractive cataract surgery.” He said physicians who have done refractive surgery likely don’t have to change their routine too much in order to incorporate the LAL.
Postop patients wear UV-protective glasses for up to 5 weeks, Dr. Hoopes said. The process begins by sitting down with the patient over multiple visits, anywhere from three to five extra visits. Traditionally, Dr. Hoopes sees cataract patients at 1 day, 1 week, and 1 month postop, but with the LAL, the work starts at 1 month postop. Patients must be informed preop about the extra visits and that they must come in several times a week, he said.
“The promise of the LAL is to have a product where a month after surgery you can fine tune and personalize results to the patient,” he said. However, a challenge is you must pick the right patients. For example, patients’ eyes must be able dilate to a certain degree, and if they can’t, they are not eligible for this procedure, Dr. Hoopes said. The light adjustments are not any more difficult than doing a YAG capsulotomy, but the patient must be able to hold steady for 2 minutes.
Another challenge is the potential for changes to the eye. “The promise of the lens always was that we could fine tune the results accurately and by the end of the process have patients completely corrected in their vision,” Dr. Hoopes said. “The truth is there’s still the possibility of having small prescriptions even at the end of light adjustment. We know people can still change 2–4 months down the road after cataract surgery just by how the capsule heals. Even the LAL doesn’t prevent the possibility of more long-term changes to prescription, such as astigmatism over time.”
While there’s no surgical learning curve, Dr. Hoopes stressed the importance of communication about the treatment process. “As long as I communicate the time period with the patient, the expectation of the work needing to be done a month later, almost every LAL patient has been excited about the technology and willing to undergo the lengthier process. They feel like they have a say in their surgery and outcome.”
Dr. Hoopes noted the ActivShield advancement, which allows patients some flexibility with the ultraviolet glasses, but he said even before this update, he had very few cases of patients complaining about wearing them. He still recommends patients wear the glasses as much as possible.
One future advancement Dr. Hoopes hopes to see is the ability for physicians to make the decision to lock a patient in. Currently, it’s the software and the light adjustable device that determines when it’s time to do the lock-in treatment. However, he noted that in some cases, he’s had patients who were happy with their vision before the lock-in process. “I would love the opportunity as the surgeon to be able to bypass treatment and make the decision to lock in the patient right now if the patient is happy with their vision. Now I might have to do 1–2 small adjustments or even sham adjustments,” he said. Sometimes these small adjustments can even make patients less happy with their vision. A future option to delay adjustments several months could also be advantageous, Dr. Hoopes added.
Neda Nikpoor, MD
Dr. Nikpoor said that her partner, Alan Faulkner, MD, was one of the first to adopt the LAL upon launch and the first to bring the technology to Hawaii. Dr. Nikpoor started using the LAL in February 2020.
Dr. Nikpoor implanted the lens in her first set of patients right before the pandemic. “During this time, we were still seeing our postops, and it gave us some time to play around with the LAL,” she said. “The timing was perfect for us to integrate something new and have time to understand it and follow those patients closely.”
It’s the only lens that Dr. Nikpoor said she wants to put in post-refractive patients. “For a practice that does high-volume laser vision correction, it’s a must-have.” She added that some patients in her practice have had RK or LASIK years ago and are coming back. You want to be able to offer them the best technology designed for their eye, she said. From a practice growth perspective, it gives you a competitive edge to be first in the market, Dr. Nikpoor added. “We’ve gotten referrals from other cataract surgeons because patients are asking about it.”
The LAL is also a great option for virgin eyes, she said. They did a review of their cases and found that there were high levels of spectacle independence with a mild amount of blended vision. On average across all patients, the range of vision was similar to an extended depth of focus lens. “The range and quality of vision are excellent, making LAL a great option for any patient,” Dr. Nikpoor said.
One obstacle to adoption is figuring out the workflow because of the extra visits, and the visits take a while, Dr. Nikpoor said. In her practice, this involved finding time on the schedule to do adjustments twice a week and training technicians. “We would have a specific tech who was good at assessing dilation, getting patients dilated, programming, being with us for the treatments, etc.,” she said. “We have patients coming in clusters of three, so we have three patients getting refracted close to each other and getting dilated together, and we found that to be useful.”
Dr. Nikpoor said the LAL is an “easy sell” with post-refractive patients. “I explain to them that even with all the measurements we take, we’re still going to be off 10–20% of the time,” she said. “I show them their scans, and I show them why their RK or LASIK makes it challenging to determine the correct lens power.”
For other patients, Dr. Nikpoor will still explain how it’s necessary to enhance any diffractive or premium lens 10–15% of the time. Then she explains the alternative of putting a lens into the eye where all the adjustments are built into part of the process and any fine tuning can be done without an additional surgery. She added that the LAL is a desirable option for some patients who don’t know what they want and find it stressful to commit.
Dr. Nikpoor said the ActivShield technology has been a helpful advancement. Though she noted that she’s only had one patient who was not compliant with the glasses before ActivShield, she did have to end up exchanging that patient because of stray UV light. It was a difficult case, Dr. Nikpoor said, but when she did the exchange, the ActivShield technology was available, so this was one of her first patients with the update.
Dr. Nikpoor is eager to see the ability to add or remove extended depth of focus in the future. “Even though it’s a monofocal, it gives you a little more extended depth of focus than a typical monofocal, and when you do the first adjustment in a myopic direction with a myopic target, on the near eye, you get even more extended depth of focus,” she said. “But I think they will figure out a way to induce even more and give us the ability to induce it or take away if we want to.” Another exciting future advancement is the potential for the company to create a custom light adjustment profile that would help offset some corneal aberrations, Dr. Nikpoor said.
[template id=14580]Jonathan Solomon, MD
Dr. Solomon was aware of the LAL technology for a number of years before deciding to use it in his practice. “I was eager to get my hands on the technology with the idea that it would be a useful tool for almost all patients,” he said.
Dr. Solomon stalled his official adoption of the LAL for about 6 months after getting the opportunity to start using it, having some hesitation after looking at the numbers and assessing the effort it would take to incorporate it. Ultimately, he did decide to bring it into practice and was surprised that the adoption was less arduous than he originally thought. Patients also gravitated to the technology with very little effort. “Despite the added work that is associated with it, the patient flow can be effectively streamlined easily, and the patient expectation is met in the overwhelming majority of cases,” Dr. Solomon said.
With the LAL, Dr. Solomon said the first and second eye are done very close together so their adjustments can be timed accordingly. You have to wait for the tissue to heal, for the corneal edema to resolve, and get a steady refraction, he said. Being able to treat both eyes around the same time for adjustments is important because that’s more time in the postop window, and of course there’s a lock in where after you’ve achieved your ultimate refractive outcome, you’re going to fix the lens in that current state.
There’s more work that goes into an LAL patient, and the mindset for the patient needs to be managed ahead of time. “People hear ‘adjustment,’ and there’s a certain mentality that it’s infinite, that you can move this around, and that’s not the way it works, and you have to set a healthy expectation.”
“The accuracy and ability to precisely hit targets is impressive,” Dr. Solomon said.
In the future, Dr. Solomon said one advancement he would be looking for is the option of a multifocal or true EDOF version of the optic itself.
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If you have to remove the lens
Though the need to remove the LAL is infrequent, it can prove challenging, particularly if the lens has already been locked in. The LAL becomes brittle after it has been treated and locked in, Dr. Fram said. “In the previous generation of the LAL without ActivShield, when trying to stabilize the lens with serrated forceps, it would break into tiny pieces.”
Dr. Fram suggested that the best approach is to provide counter traction with a Sinskey hook and use serrated scissors that can hold the lens while cutting. “I have also found that enlarging the main incision to 3.5 mm is helpful, as the lens is silicone and thick and may be difficult to get out of a sub-3 mm incision.” Removal after lock-in is a rare occurrence with the development of the ActivShield, Dr. Fram said, “however, if you put an IOL in, you should know how to remove it safely in the circumstance that it becomes necessary.”
Dr. Solomon noted that he has only had to do one removal before the lens was locked in. During one of his insertions, the injector system caused inadvertent damage to the lens, and he had to explant it immediately. He mentioned that it does require attention because it’s a gummy, silicone lens. It’s relatively soft at that stage, so be prepared by using good instrumentation, he said.
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When first starting with the LAL technology
Dr. Fram offered the following recommendations when first beginning with the LAL.
- Picking the IOL power: Pick on the first hyperopic side of plano so you can add in power and allow for an effective extended depth of focus by changing the spherical aberration profile centrally. In the non-dominant eye, adjust to effectively cause more negative spherical aberration and increase the depth of focus, she said. “However, if this is a post-LVC or RK eye with an already aberrated cornea, use your normal post-LASIK formulas and pick as you would to avoid big misses in refractive target and large treatments to get to plano.”
- Higher order aberrations and expectations: Surgeons should be sure to look at Placido imaging and ablation pattern to give proper counseling of the postoperative outcome. The LAL adjustments are not wavefront guided, and if the RMS is high and/or the Placido imaging is distorted, the patient’s best vision may be with a scleral contact lens.
- Post-hyperopic LASIK vs. post-myopic LASIK: The hyperopic LASIK patient is challenging in that the K readings are often a moving target despite multiple measurements. This makes the ability to adjust postoperatively ideal in many ways. However, in an eye that already has negative spherical aberration on the corneal topography, it may not be ideal to add a negative spherical aberration IOL. In theory, surgeons want to place an IOL with a neutral or positive spherical aberration in these patients to counteract the negative spherical aberration of the cornea. “In our practice, we perform LAL on hyperopic LASIK patients with neutral to slightly positive spherical aberration measured by wavefront aberrometry patterns to avoid potential issues with image quality,” she said. “Alternatively, in patients with myopic LASIK ablation patterns we are comfortable using this technology as long as the ablation is centered and the Placido imaging is regular.”
- Intraoperatively: Practice putting in three-piece IOLs, making the incision at least 2.75–3.0 mm at first to avoid Descemet’s detachments when positioning, centering the rhexis on the visual axis, 4.8–5.0 mm, cleaning the posterior capsule well to avoid delay in LAL treatment due to fibrosis of the capsule, and polishing the anterior capsule to avoid capsule contraction, placing the haptics at 6 and 12 o’clock for better IOL stability and less striae in the capsule.
About the physicians
Nicole Fram, MD
Advanced Vision Care
Los Angeles, California
Phillip Hoopes Jr., MD
Hoopes Vision
Draper, Utah
Neda Nikpoor, MD
Aloha Laser Vision
Honolulu, Hawaii
Jonathan Solomon, MD
Director
Solomon Eye Physicians & Surgeons
Bowie, Maryland
References
- Abulafia A, et al. Accuracy of the Barrett True-K formula for intraocular lens power prediction after laser in situ keratomileusis or photorefractive keratectomy for myopia. J Cataract Refract Surg. 2016;42:363–369.
- Haigis W. Intraocular lens calculation after refractive surgery for myopia: Haigis-L formula. J Cataract Refract Surg. 2008;34:1658–1663.
- Lawless M, et al. Total keratometry in intraocular lens power calculations in eyes with previous laser refractive surgery. Clin Exp Ophthalmol. 2020;48:749–756.
- Yeo TK, et al. Accuracy of intraocular lens formulas using total keratometry in eyes with previous myopic laser refractive surgery. Eye (Lond). 2021;35:1705–1711.
- Wang L, et al. Evaluation of total keratometry and its accuracy for intraocular lens power calculation in eyes after corneal refractive surgery. J Cataract Refract Surg. 2019;45:1416–1421.
Relevant disclosures
Fram: RxSight
Hoopes: RxSight
Nikpoor: RxSight
Solomon: RxSight
Contact
Fram: info@avceye.com
Hoopes: pchj@hoopesvision.com
Nikpoor: drneda@alohalaser.com
Solomon: jonathansolomonmd@gmail.com
