LASIK for reading
We often have patients that come to SharpeVision MODERN LASIK to see whether we can help with their near vision. The condition, called presbyopia, affects everyone typically around the age of 45 and older. This occurs because the natural lens of our eyes becomes less and less flexible as we age. One way of looking at it is that no one can have perfect distance vision and perfect near vision in both eyes forever. This is why people get either bifocals, reading glasses, multifocal contact lenses, or LASIK for reading vision. There is hope!
If you’re not interested in more detail, skip down to the section that says “Lasik surgery for reading“
If you are interested in the details, I will try to explain the way our eyes work as simply as possible in this blog post. First, imagine anything that you are looking at whether it is far away or very close. There is light reflected off of the thing that you are trying to see, or there is actually light being emitted from the thing that you are trying to see, such as a lightbulb. We know that there’s light reflected off an object, because without light, we can’t see! Pretty obvious! Imagine that object you want to see having strings coming out of it in all directions. Any object that you see has infinite light rays emanating straight out from it, whether it is reflected or a direct light source. Imagine now that each of those light rays is a string. You can imagine that the strings start from the object and go straight out from it in all directions. Those “strings“ come directly at you and at your eye. (And they come super fast. The speed of light is about 186,000 miles per second!) Those strings are getting farther and farther apart, but there are infinite strings so if the object is far away, those strings are nearly going the same direction.
When an object is close to you, say 2 feet away, those strings are diverging (moving apart) more quickly and need more focusing than a distant object where the “strings“ (light rays) are diverging less rapidly. The light rays are always moving apart, but for calculating glasses and vision, we consider the light rays to be parallel at about 20 feet away, which is where the “20/20” vision is the standard distance for eye measurements. It’s about the same as infinity for the purpose of discussion. Another way is to imagine that for distant objects, two strings are next to each other but nearly the same direction, whereas a near object has those two strings diverging (moving apart) rapidly. Each of those strings, or light rays, is bent when it goes through your eye. It is bent and comes to a focus in the back of your eye at the retina. A near object, where the two light rays are diverging rapidly will require more focusing than a distant object where the light rays are nearly parallel. This is why you need more focusing or “add“ from reading glasses for near objects and less focusing for distant objects.
Typically your eye focuses about 60 units. 40 of the units are from your cornea, the clear dome over the colored part of your eye. 20 of the units come from the lens of your eye.
This example also help you understand why nearsighted people can see up close whereas farsighted people can see better for distant objects. A nearsighted person has too much focusing power in their eyes, so they need less focusing power to see distant objects clearly. This is why glasses for nearsighted people are labeled -4 so that the contact lens or glasses that they place on their eyes decreases the focusing power. The contacts or glasses are concave (thinner in the middle, thicker on the edges) so the lens causes the light rays to diverge (move farther apart) to decrease the focusing power.
A farsighted person is just the opposite. They need more focusing power than their eyes are capable of. They typically recruit use lens of their eye to add focusing power. As I said before, in a young person, the natural lens can focus up to 10 units. This allows someone who is farsighted to not even know it until they are in their late 30s or 40s when they start needing reading glasses sooner than usual. Their eyes need additional focusing power. When they get glasses they have a +4 or similar prescription to denote that they need more focusing power. The lenses are convex or thicker in the middle and thinner at the edges.
At SharpeVision MODERN LASIK, we change the curvature of your cornea with a laser to allow you to have more focusing power than you currently have or less focusing power than you currently have depending on your anatomy of your eye. Pretty incredible, but absolutely true!
The lens of our eye sits behind the colored part of your eye (the iris) and is an amazing structure. It’s about the size of an M&M candy. It’s what gets cloudy when we’re in our 60s and 70s and causes us to need cataract surgery, or replacement of the natural lens with a clear artificial lens. The lens of our eye is very flexible when we are young and by the time we are in our mid-50s it becomes completely rigid or inflexible. At about the age of 45 that flexibility decreases to the point where the lens of our eye cannot focus or bend the light rays coming from a near object enough to allow us to focus. We need additional focusing which explains why over-the-counter reading glasses are labeled +1.50. This allows us to focus 1.5 units more than our natural lens can do when we’re over 45 years old. A young person has a very flexible lens that is capable of approximately +10 units of focusing power when we are very young so that the near vision is never difficult. The exception to this is a child who is highly farsighted and needs more focusing than their eyes are capable of.
LASIK surgery for reading
Some of our patients have not needed any glasses at all until the age of 45 or older. This is called “emmetropic presbyopia”. Don’t get hung up on the words. What it means is that you have good distance vision, but after the age of 45, you begin having difficulty seeing near objects. Typically it is first noticed in low light, small print, or poor contrast, such as a restaurant menu.
LASIK eye surgery for reading is potentially possible. The best way to figure this out is to come into a SharpeVision MODERN LASIK for your free comprehensive consultation. We will discuss Monovision with you and simulate it with a contact lens. If you’ve never worn contacts, don’t worry. We will perform the exam and place a contact lens on your eye simply to simulate “LASIK reading glasses.” Typically, this answers the question “Can LASIK fix reading glasses?“ LASIK eye surgery for reading involves performing LASIK eye surgery on one eye for near vision and not the other (which has good distant vision), but can be performed on both eyes, if necessary. The laser increases the curvature of your eye which allows you more focusing power and therefore better near vision. Depending on your age, your needs, your anatomy, overall health, and eye health, you may be an excellent candidate for LASER eye surgery for reading.
Does LASIK work for reading?
LASIK surgery for reading (Monovision) can be an excellent option for anyone who has great distance vision but find themselves having trouble seeing near objects when they approach the age of 45 or older. I have observed that many of my patients think that they will not be able to tolerate Monovision, which is where we have one eye focus better for near objects and one eye focused better for distance objects. In reality Monovision works probably 99% of the time. We demonstrate it in the office, discuss it, and show you what LASIK for reading looks like with a contact lens trial. You may wear the contact lens only in the office (in which case we will insert it and remove it). Sometimes we have patients who would like to see if LASIK works for reading, and they spend the day wearing the contact lens, but have us take it out toward the end of the day. Some people would like even more confirmation that LASIK does work for reading. These patients can take the lens home and try it for a week or more as long as they are comfortable inserting and removing the contact lens. If they find that the contact lens works just fine for them, they can then have LASIK for reading that can reproduce the contact lens trial vision in a permanent way. The contact lens focuses near images better than you can without any contact lens in your eye. This does slightly blur your distance vision, but only in the eye with a contact lens. The other eye still sees well at distance and there are no problems seeing both distance and near objects. Sometimes, it takes a little while to get used to it and sometimes patients like it immediately.
Can LASIK correct reading vision?
The answer is, “absolutely!“ After a trial lens period, we can perform LASIK for reading vision exactly as you experienced it with the contact lens trial. This way LASIK can correct reading vision and you can trial the contact lens to answer the question, “does LASIK work for reading?” Book your free consultation at SharpeVision to trial Monovision and get rid of your readers today!
-Dr. Matthew Sharpe