September 2020

REFRACTIVE

YES Connect
Insights on the Light Adjustable Lens


by Liz Hillman Editorial Co-Director


Office-based IOL light adjustments using the Light Delivery Device
Source: Arturo Chayet, MD

 

Thank you to Julie Schallhorn, MD, and Claudia Perez-Straziota, MD, who managed the YES Connect column for the past year. Michael Patterson, DO, and I, as the new co-editors of the column, look forward to guiding topics of interest and importance to the young eye surgeon audience.
For our first column, we recognize that a critical part of being a successful refractive cataract surgeon is keeping up with the latest and greatest refractive options for our cataract patients as the technologies available continue to evolve. Today’s world of increased patient demands for predictable and accurate postoperative outcomes as well as an expectation for spectacle independence has created much interest in learning more about technologies such as the Light Adjustable Lens (LAL), which is discussed in this month’s YES Connect column. We asked two experts to share their thoughts and experiences with the LAL. I have learned so much from our discussions with these two and hope you will find their insights useful in staying up to date.

—Soroosh Behshad, MD
YES Connect Co-Editor

Arturo Chayet, MD, has been working with the Light Adjustable Lens (RxSight) for nearly 20 years, implanting the first iteration of the lens in 2002. So, he has a pearl or two to offer young eye surgeons when it comes to this technology, which, though FDA approved in 2017, only began its commercial launch in the U.S. in September 2019.
The Light Adjustable Lens is a three-piece, silicone lens that is approved currently for patients with 0.75 D or more of corneal astigmatism and without preexisting macular disease. Outside the U.S., the lens can be for presbyopia-correcting purposes. The lens is adjusted postoperatively in an in-office procedure with a Light Delivery Device that applies a customized UV light treatment to the reactive lens, with up to three treatments possible. A final procedure “locks in” the treatment. In the time between lens implantation and the “lock-in” procedure, the patient needs to wear UV light-protective glasses that are provided by the surgeon.
“This is a lens that you can adjust once the intraocular lens is inside the capsular bag. Usually we adjust it after 2 weeks. The benefit is we can achieve emmetropia,” Dr. Chayet said. “We don’t need to worry about IOL placement in terms of a toric lens that you might need to place in the axis of astigmatism. Obviously, we need to do good calculations, but if we miss by 0.5 D or 1 D, we’ll be able to adjust that.”
Dr. Chayet said this lens achieves the highest percentage of eyes within ±0.5 D of target, with more than 95% of eyes achieving this.
“That’s something you don’t get with any other IOL,” Dr. Chayet said.
According to the FDA pivotal clinical study that confirmed safety and efficacy of the Light Adjustable Lens, it “achieved higher ‘percent reduction’ in postoperative manifest cylinder and MRSE [manifest refraction spherical equivalent], respectively, than the control” and it “demonstrated the rotational stability.” A press release from RxSight at the time of the IOL’s FDA approval stated that patients with the Light Adjustable Lens, compared to control, were twice as likely to achieve 20/20 UCVA or better at 6 months postop.
“This is the first time in IOL history that we get that kind of LASIK result, which is 93% within 0.5 D of intended correction,” Dr. Chayet said.
Dr. Chayet also noted being able to avoid some higher order aberrations, such as glare and halo, that can occur with other lenses.
Bryan Lee, MD, JD, who has been using this lens since October 2019, has been happy with his results and has observed high patient satisfaction. He said he is implanting it in about 10% of eyes, with high interest in the post-refractive patient population.
“Many of the patients opting for this
IOL are the toughest to achieve a good refractive outcome in because of irregular corneas and difficult power calculations, and I am comfortable offering it to them because I think this is the best available technology for them,” he said.
Cataract surgery with the Light Adjustable Lens is the same as with a standard IOL, Dr. Chayet said. He conducts it through a 2-mm incision with the lens implanted through a 3-mm incision at the temporal axis. The Light Adjustable Lens is suitable for most patients, but if there is a risk for the patient needing silicone oil in the future, that could be a possible contraindication, though not an absolute one, Dr. Chayet noted. Dr. Lee listed asteroid hyalosis, inadequate dilation, photosensitizing medications, significant retinal disease, and nystagmus among the contraindications.
“Because the wavelength used by the Light Delivery Device could theoretically reactivate herpes simplex, the surgeon should discuss this with a patient with a history of herpes keratitis,” Dr. Lee added.
For the young eye surgeon, Dr. Chayet said the technology is easy to learn with a slight learning curve if you’re not used to implanting a three-piece, silicone lens. The UV light treatment is similar to a retina laser or YAG laser treatment, he said.
There is a learning curve to setting the patient’s expectations. The patient needs to understand that they’ll need to return to the clinic 2 weeks postop for light adjustment treatments, according to Dr. Chayet. The key to the adjustment is a clean refraction, Dr. Lee said.
“I tell all patients to use artificial tears frequently to help stabilize the refraction as soon as possible. Patients should know that they will have to make multiple visits for adjustments and will need to be dilated fully each time,” Dr. Lee explained, noting that he usually does the first adjustment 2 weeks postop but will wait 6–7 weeks for RK patients. “Typically, we get a refraction on the iTrace [Tracey Technologies], then a manifest refraction. Most patients need at least two rounds of dilating drops before they are ready for the treatment. We enter the manifest refraction and the targeted refraction into the Light Delivery Device, then the patient sits at the machine just like a slit lamp. You use a contact lens similar to what you would use for a YAG. Each treatment lasts 2 minutes or less, and the IOL takes about 2 days to finish changing.”
Dr. Lee also said he usually recommends that even patients without a history of monovision try slight myopia in one eye. The adjustable lens allows patients to try blended vision at low risk thanks to the ability to adjust them back to plano if preferred.
There might be some fears on the surgeon’s and patients’ part regarding UV light exposure until the final treatment is set. Dr. Chayet said the current lens even in ambient light can still be affected and thus requires use of the filtering glasses even inside. A next-generation lens is in clinical trials that will not be impacted by ambient light, he said. Another fear is retina damage from the UV light treatments. Dr. Chayet said in 20 years of research with this lens, retinal damage hasn’t been observed. It is important, however, for surgeons to identify and tell patients to stop any medications or supplements that could cause photosensitivity for several weeks prior to the treatment.
“The young surgeon needs to know patients need to be out of those medications to prevent phototoxicity during the treatment,” Dr. Chayet said.

About the doctors

Arturo Chayet, MD
CODET Vision Institute
Tijuana, Mexico

Bryan Lee, MD, JD
Altos Eye Physicians
Los Altos, California

Relevant disclosures
Chayet
: None
Lee: None

Contact
Chayet: arturo.chayet@gmail.com
Lee: bryan@bryanlee.pro

Insights on the Light Adjustable Lens Insights on the Light Adjustable Lens
Ophthalmology News - EyeWorld Magazine
283 110
220 136
,
2020-08-31T09:54:56Z
True, 9