One of the most difficult questions to answer, and the one most often asked by our patients, is what is the best lens for me for cataract surgery? The answer is difficult because it is a highly personal choice, and the decision is usually final. The lens you choose today will likely be the lens you will be looking though for the rest of your life. Naturally, as eye surgeons, we take the decision very seriously.
As of this writing, there are over 20 different types of lens implants in circulation around the United States. And every few months there is a new one. Not infrequently do I tell my patients that if they wait 6 months, our conversation may be different. The lenses I implant today are not the same ones I implanted last year. We are constantly learning from our own and our fellow surgeons’ experiences. This is why we never want to rush into cataract surgery until the patients’ symptoms are severe enough that they require immediate action.
So where do we start? A thorough and detailed complete eye exam in addition to imaging of the front of the eye (cornea), the back of the eye (retina), the length of the eye (A-scan), and the current glasses prescription (refraction). We evaluate for any concomitant eye disease such as dry eyes, corneal dystrophies, aging changes of the eye such as glaucoma and macular degeneration and many more. Some of these conditions lend to worse outcomes with some of the advanced technology lenses on the market today.
Next is the discussion with patients about what they are used to and what are their vision goals after surgery. One of the most straightforward cases is when a patient is used to having excellent distance vision and is comfortable wearing reading glasses. In my practice, this is the most common presentation and one in which the decision is relatively clear. I typically suggest implanting a lens that would aim to deliver excellent distance vision, typically a monofocal lens. These monofocal lenses delivery the highest quality vision in the distance. If a patient is also interested in spectacle independence, in other words, where they do not want to wear distance glasses, I will recommend correcting their astigmatism at the time of surgery. Astigmatism is a very common condition that causes blur of vision that can usually be corrected with glasses. If a patient is not interested in wearing distance glasses after surgery, they can choose to have an astigmatism correcting lens implant (toric). In this scenario, our aim would be to provide excellent distance vision without glasses. In order to read the computer and anything closer, patients would need to wear reading glasses at all times.
What if patients want even more freedom without glasses? There are many options to achieve these goals. One of the longest tried and true methods is what we call “blended vision”. With blended vision, or mono-vision, we would target one eye to be able to see far, and the other near. Some patients are already used to this “optical set-up” because they have worn contact lenses that offered them mono-vision. There are certainly some drawbacks with mono-vision. As with any choice when it comes to IOL (intraocular lens) selection. The most common one being the reduction in depth perception.
Another choice is the use of extended depth of focus lenses. As of this writing, the lens I am currently using for this purpose is the Tecnis Eyhance IOL. The benefit of extended depth of focus lenses is that they may give patients both excellent distance and some intermediate vision. For example, they can drive without glasses, see the dashboard, maybe their phone and the plate of food clearly. In most cases, patients will still need reading glasses for small print and computer.
One of the other popular choices on the market today are lenses that are designed to provide patients the full range of vision – distance, intermediate and near. Typically these are called multifocal or trifocal lenses. The benefit of these IOL’s is that for most situations patients are free from glasses. However, as with all other cases, there are definite drawbacks. In my personal practice I only use multifocal or trifocal lenses in less than 5% of my patients because often the side effects of nighttime halos, glare and starburst are not worth the benefit of spectacle independence.
So… what is the best lens for cataract surgery? It depends! There is no perfect lens…but maybe one day there will be. To best care for our patients, we stay abreast of all the developing technology and the practical experiences with these new lenses. The “holy grail” of cataract surgery is a lens implant that will restore the vision we had in our youth without any of the side effects…but we don’t yet have this lens. Until then, your surgeon will help you navigate the choices available, discuss the potential drawbacks, and help you pick the best lens for you.
Dr. Alexander E. Voldman is a cornea and cataract surgeon specializing in advanced technology intraocular lens implants and refractive cataract surgery.