The only lens that can be customized after cataract surgery
Imagine not having to worry about patients’ complaints about refractive errors after cataract surgery. Imagine patients not having to wonder if they made the right decision between monovision or full distance correction. Well, this is now a reality as the “truly disruptive” technology of RxSight Light Adjustable Lens (LAL) will become commercially available in early 2020. It is the first and only lens that can be adjusted after cataract surgery.
The unique difference of LAL
This IOL is very similar to monofocal lenses currently on the market in size, design, haptics, material (silicone), squared-edge back surface, and optical zone. The procedure is performed just like a standard lens implant. The LAL is priced and reimbursed similar to other premium IOLs and is designated by CMS as such, and is therefore billable to patients. What makes the LAL unique is that it is made from a special material that changes shape when exposed to UV light. This allows the eye care practitioner to modify the lens for residual refractive error (sphere and cylinder) three weeks after implantation using an ultraviolet light laser known as the Light Delivery Device or LDD.
What makes the LAL unique is that the lens is made from a special material that changes shape when exposed to UV light, so refraction can be adjusted after implantation.
After the residual refractive error is measured with a standard phoropter and the optimal refractive error for each eye is determined, the LDD exposes the patient to about 90 seconds of light to “adjust” their refractive state to the desired target. The patient then should be rechecked in two to three days. “If the patient likes the unaided vision, we can ‘lock in’ this refraction. If not, we can make a second adjustment” and two to three days later, lock in their preferred endpoint, explained John Doane, M.D., an ophthalmologist who participated in clinical trials for RxSight, in an article for EyeWorld.
This “lock-in” process involves photopolymerization of the macromers within the LAL via UV light. Prior to locking in the prescription and 24 hours afterward, the patient must wear UV light-blocking spectacles to protect against unintentional changes to the IOL.
Reducing variability and stress
The LAL procedure is less stressful for the ECP since the outcome is not dependent on absolutely accurate post-IOL refractive error or individual healing variability. It’s also less stressful for patients because they don’t have to decide pre-operatively whether they prefer better uncorrected distance, mid-range, or near vision. And instead of requiring a refractive “touchup” of the cornea with PRK or LASIK, the LAL can be adjusted after surgery quickly, painlessly, and in a non-invasive manner.
Even small amounts of residual astigmatism can now be safely and accurately treated. Once the ECP and the patient decide on the ideal final refractive error, the number is dialed into the LDD. Unlike treating living tissue such as the cornea, which can be variable, adjusting the IOL is predictable and not dependent on wound healing. The first two patients I observed who had this procedure in clinical trials were better than 20/16 uncorrected! One patient had 0.50D of cylinder corrected, allowing her to achieve 20/12 uncorrected vision.
In clinical trials, LAL patients achieved UCVA of 20/20 or better at a rate of two times that of patients receiving a monofocal lens, as well as less glare and halos.
Clinical trial results showed that patients receiving the RxSight LAL:
- Achieved UCVA of 20/20 or better at a rate of two times that of patients receiving a monofocal lens
- Nearly 92 percent of patients receiving the LAL achieved results within 0.50D of the intended target, compared to about 70 percent for every other lens
- Achieved superior quality of vision measures in all of the following categories: best corrected vision, patient vision rating, driving difficulty, and dim light or mesopic vision
- Tested superior in contrast sensitivity measurements and had a reduced level of vision issues such as glare and halos
The RxSight LAL is a welcome innovation as the first and only IOL that allows optimization of vision after cataract surgery. It takes away the stress of IOL predictability, which can be affected by numerous causes ranging from dry eye, inaccurate biometry, or even capsular changes post-surgery. Patients can preview their vision options before finalizing their choice. LAL truly offers peace-of-mind decision making both before and after cataract surgery.
The views expressed above are of Dr. Karpecki and do not necessarily reflect those of Rendia.