The cover story in this issue of Ocular Surgery News explores a promising new breed of accommodating lenses that are likely to drive excitement in refractive cataract surgery. They face a challenge to widespread use, though, because across the U.S. only about 12% of cataract patients receive a premium IOL.
Why is adoption so low? It’s not the higher cost of these lenses. A number of market research studies have shown that 80% of cataract patients (from all walks of life and parts of the country) are willing to pay extra for better vision if they understand what is being offered. The biggest barrier is a lack of physician confidence in the technology.
Why do surgeons lack confidence in premium IOLs? Research suggests there are two reasons. First is a lack of refractive accuracy. Many surgeons struggle to get even half of their patients to a refractive outcome within 0.5 D of the intended target — an important threshold for patient satisfaction. Second is the perception by surgeons that these lenses cause many patients to have unsatisfactory visual results with glare and halos.
Both of these problems — refractive inaccuracy and glare/halos — can be overcome in most patients if we do one thing: treat the patient’s dry eye. We recently conducted a study to determine the impact of treating dry eye on these two problems. We selected 100 cataract patients with dry eye, defined as any degree of corneal staining and a reduced tear breakup time below 10 seconds. Bill Trattler has previously shown that these patients account for about three-quarters of our cataract surgery population, which we confirmed in our population as well.
We performed preoperative biometry on these patients before treating their dry eye, then again 1 month after treating them with Xiidra (lifitegrast 5%, Novartis) twice daily. We also measured the 1-month postoperative refractive outcome to see which biometry measurement — before or after dry eye treatment — was more predictive of the final outcome. Not surprisingly, the biometry performed after lifitegrast treatment was significantly more accurate than that performed before. Our likelihood of reaching the important window of ±0.5 D was almost twice as great when dry eye was treated first.
What about glare and halos? We know these symptoms are much greater (and satisfaction is much diminished) when the cornea has greater than 5 µm of higher-order aberrations. Not surprisingly, higher-order aberrations also were significantly reduced by the use of lifitegrast, with half as many falling above 5 µm after treatment.
Lifitegrast is just one treatment for dry eye, and in this study it was used alone for management of this disease. It’s likely that other treatments would work as well, alone or in combination. What’s important is that the patient is compliant with the dry eye treatment; in educating our lifitegrast patients, we made it very clear that the lifelong outcome of their vision would depend on their diligence in following the treatment plan for the month before “final measurements.”
The ophthalmic drug and device industry has committed itself to providing us with devices, implants and tools to achieve high patient satisfaction. It is up to us to identify the patients who need their dry eye treated, to educate them and to encourage their compliance, so they will achieve the results with these lenses that they’d expect and deserve.
Disclosure: Hovanesian reports he is a consultant for Novartis. The study described was independent research funded by a grant from Shire.