Joel Hunter, MD Refractive Surgeon, Hunter Vision Updated 10/31/18 11:35 AM
Refractive lens exchange involves, as you may expect, exchanging a lens. Your lens, in particular, exchanged for an acrylic lens with perfect optics that will last a lifetime. “Why wouldn’t you just exchange for the new hi-tech lens as early as possible?” you may be asking yourself, in a whisper quiet enough to ensure your natural lens doesn’t hear you. It’s an excellent question.
What decides when the time has come for an upgrade?
There’s a simple answer with a slightly less simple explanation. The best age to get an upgraded lens RLE is when it’s actually an upgrade. Yes, I know I wrote just a few lines north of this sentence about perfect optics. I meant that. The permanent intra-ocular lens (IOL) placed in the eye during RLE is a wonder of optics. There’s this fault of the vast majority of lenses, in everything from cameras to projectors, called spherical aberration. It happens when the middle of a lens focuses the slightest bit different than the periphery of the lens. Really great lenses have very low spherical aberration. The lenses used in RLE have zero. Zero! I will never not find that amazing.
So I meant what I said about perfect optics with a new lens, and I meant what I implied when I implied there’s an age where RLE isn’t an upgrade. These facts can both be true because there’s more to a lens than its optics. More specifically, I should say there can be more to a lens than optics. With the glass lenses we see every day, like the one on your phone’s camera, nothing beats optics. The whole point is creating the most optically perfect glass surfaces possible.
Optics vs. focus
Our natural lens, however, does something for about five decades that none of those lenses are capable of doing. It can flex and change shape, becoming rounder or flatter depending on where we’re looking. It’s got built in autofocus. This autofocus—the natural ability to seamlessly see near and far—is an advantage for vision so great it actually matters more than optics. If given a trial day with perfect autofocus and repeating that day with perfect optics instead, everyone would pick the vision from the first day.
This is relevant because the natural lens we were gifted with from birth is capable of autofocus we can’t even come close to with artificial lenses. This remains true for as long as a reasonable amount of autofocus remains. Most people age 45 to 50 will feel like they’ve lost their autofocus, but the truth is a significant amount still remains. Sure, you may have to wear readers, but through those readers you’ll notice you can hold a book pretty close or pretty far and it’ll stay in focus. That’s your natural lens, noble and weakened, still providing the autofocus it has left.
Then one day, there’s just not enough focusing power left in your natural lens for it to help with anything. Depending on your prescription, it may be anywhere from age 50 and up. At that point, your natural lens has no meaningful advantage, and several disadvantages, to an artificial lens with perfect optics. The IOL is officially an upgrade.
New lenses to last a lifetime
There is no way to compete with a young, natural lens in autofocus. There are, however, several ways to accomplish glasses-free near and distance vision, and that’s the purpose of autofocus in the first place. RLE can restore the ability to see near and far away without glasses. You can get new lenses with perfect optics enabling glasses independence that can last a lifetime. The best age to do that is when that option truly becomes an upgrade.