Excitement surrounds advances in presbyopia correction

Issue: March 10, 2011

ByRichard L. Lindstrom, MD

Richard L. Lindstrom

Presbyopia remains the holy grail of refractive error treatment. The reasons for this are easy to discern.

In advanced countries, approximately 30% of the population is presbyopic. In the U.S., this translates to nearly 100 million presbyopes, and in the world, more than 1 billion. About half of these presbyopes are emmetropic, meaning their distance refraction is between –0.75 D and +0.75 D of defocus. Roughly 25% are myopic and 25% hyperopic. Thirty percent have 1 D or more of astigmatism as well. For all of them, their uncorrected near vision presents a significant handicap, and some find their need for reading glasses or bifocals detracts from their quality of life. Many are looking for a better option and can afford to purchase a treatment that is superior to standard presbyopia-correcting glasses that have been available for the last 300 years or more.

In the U.S., the estimated 78 million baby boomers that drove the success of laser refractive corneal surgery for defocus and astigmatism when they were 25 to 45 years of age have now advanced to where they are 45 to 65 years old, with all manifesting some level of presbyopia. Every day I see these patients in my office asking about options for treatment. Some ask about LASIK, but when told that if they are fully corrected for distance they will be trading good uncorrected near vision for good uncorrected distance vision, they decline treatment. While a small number opt for monovision, most tell me to call them when I have a good treatment that can give them distance, intermediate and near vision with high quality of vision day and night. Basically, they want to see like the emmetrope who is younger than 35 years.

For me, the standard is the vision I can generate for a 35-year-old with low to moderate myopia using laser corneal refractive surgery. With today’s technology, these patients achieve 20/20 vision in more than 95% of cases with retention of visual quality day and night. The risks are real but rarely sight-threatening, and the benefits are great enough that in well-run centers, 98%-plus of patients are satisfied, would have the surgery again, and would and do recommend it to their friends. They have also proven that they are willing to pay approximately $2,000 per eye on average for the lifestyle enhancement they achieve.

While laser refractive corneal surgery is a discretionary spend that is affected by the health and well-being of the economy, the annual revenues generated globally are approaching $4 billion for the surgeons and industry that support them since this technology launched 25 years ago. This success story has been generated by a patient who averages about 35 years of age. Typically, the older the individual in the advanced countries, the greater their wealth, and in most cases other obligations such as educating their children, buying their first home and the like are behind them.

To me, the fundamentals suggest that the treatment of presbyopia is even a larger opportunity for ophthalmology and industry than was defocus and astigmatism. It is clear most agree, as significant human and financial capital is being invested in this arena. I would like to add some thoughts on a few select technologies that are especially intriguing to me. As a disclosure, in some cases I may consult for or own equity in the products and companies mentioned, as I have invested significant personal time and money in this area of innovation for more than a decade.

First, a very interesting new eyeglass called emPower and manufactured by PixelOptics is launching. The optics of these glasses are electronically powered and allow the entire lens to switch distance to near, either automatically based on position of gaze or manually.

Monovision contact lenses remain a viable option, and multifocal contact lenses continue to advance. In the field of corneal refractive surgery, monovision continues to dominate.

PresbyLASIK excimer laser corneal reshaping algorithms are advancing in efficacy and utilization. In many countries, including the U.S., innovator surgeons are using treatment methods off label that generate hyperprolate corneal shapes, allowing increased depth of focus. Most treat only one eye with the hyperprolate pattern, which is similar to the modified monovision used by many contact lens fitters in which a monofocal contact lens is placed on the distance eye and a multifocal contact lens on the near eye.

Several small-diameter intracorneal lens implants are in study or launching in countries where the regulatory barriers are lower. These are implanted only in the near eye, employing a modified monovision approach. They either steepen the central cornea, increase its refractive index or utilize small-diameter aperture optics. All are generating promising results.

The femtosecond laser, after a decade of serving primarily as a flap maker for LASIK, is coming into its own as a refractive tool. Technolas Perfect Vision in Germany is pioneering its application for the treatment of presbyopia with IntraCor and SupraCor procedures.

Inside the eye, lens-based refractive surgery utilizing monovision, accommodating IOLs and multifocal IOLs is growing worldwide. While monofocal IOL implantation dominates in number, with nearly 20 million IOLs implanted globally each year, these IOLs are becoming a commodity. The growing application of toric designs in combination with accommodating and multifocal IOLs is a major revenue growth opportunity for surgeons and companies. I am convinced we will have more than one accommodating IOL with well over 4 D of accommodative amplitude by 2020. Select companies well on their way in this arena of innovation include Bausch + Lomb with the Crystalens series, Abbott Medical Optics with the Synchrony and Quest projects, NuLens, PowerVision, Adoptics and AkkoLens, to name a few.