Scleral lenses can be life-altering in terms of vision, comfort, and wearability. Unfortunately, many patients leave their doctors’ offices with few instructions on how to properly care for them and the do’s and don’ts of wearing them. Below are answers to the most common questions we hear from new patients wearing scleral lenses.
How many hours can I wear scleral lenses?
Different doctors have different opinions. Some doctors recommend a maximum of 12-14 hours. However, wearing time has not been specifically studied. One study found better success when people took breaks from wearing their lenses every 4-5 hours. However, the study was not conclusive because researchers only observed that taking breaks offered temporary relief, not that taking breaks caused an improvement in wearing time. The researchers also used only one type of scleral lens at one practice with one group of scleral lens fitters. The results could have been based on how they were fitting the lenses.
What we find at Optique is that when a scleral lens fits well, there is no need to remove it multiple times during the day. The focus then is how much attention has been paid to the fit. We tend to see that the better the scleral lens edges line up with the eye, the better the fit, and the fewer problems there are.
Like many things in life, there are levels. Standard scleral lenses come in different starting designs. Some designs fit better in some eyes than others and much of that has to do with the eye condition. For example, there may be a better design for people with keratoconus. But that design may not work well for someone who had RK (Radial Keratotomy) surgery. An experienced doctor knows which designs may be best suited to you.
If a standard design does not work, the next level is a scleral lens designed around the shape of your eye. The doctors at Optique helped test one of the first machines that measure the shape of the eye for scleral lenses. This device measures the hills and valleys of the area where scleral lenses rest. Those measurements are then fed directly to a manufacturer who makes a lens in that exact shape. This technology gives another level of accuracy of fit.
The ultimate in measuring the shape of the eye is to take an impression of it—somewhat like the way a dentist takes an impression of teeth. Optique doctors use special impression material to cast an exact replica of your eye’s surface. This painless process feels like putting an eyedrop in your eye. Once we have the impression, we can create a scleral lens that is the exact shape of your eye—including the hills and valleys.
The better the fit, the longer you can comfortably wear your lenses. However, there is a limit to how long you should wear your lenses. On normal days, our patients can typically wear their lenses from the time they wake up until they go to sleep. However, if you are going to be up all night working on a project, it would be a good idea to remove your scleral lenses at some point and take a breather.
Can I nap in my scleral lenses?
We often hear this question from patients who travel for work and take long flights. Many of those patients enjoy taking a nap or two during those flights. The question is tough to answer because we know that people who sleep in any type of contact lens and wear them continuously are about six times more likely to develop an eye infection than those who wear lenses during the day. As a general rule, avoid sleeping for long periods while wearing your lenses. But what about a short nap?
Unfortunately, the answer is the same. The reason goes back to how the eye breathes while wearing lenses. There have been studies on how air flows through the lenses and the fluid behind the lenses. As soon as you close your eyes for more than a blink, the airflow through the lenses stops. Gasses in the air are needed to keep your eyes in tip-top shape so they are strong enough to fight infection. As soon as you close your eyes, the timer starts on how your eyes can defend themselves against infection. If the eyelids are closed long enough, the risk goes way up.
Can I shower or swim in my scleral lenses?
The root of this question is whether or not can water get on your lenses. To answer this, consider what is in water that could be harmful to your eyes or the lenses. Some of this depends on the type of water—such as tap water in the shower. One of the unfortunate truths about tap water is that bugs live in the water. Not the kind of bugs that crawl around, but microscopic bugs such as acanthamoeba. Acanthamoeba lives in water supplies is carried through pipes, and sometimes lives in faucets. Acanthamoeba is not usually harmful to people but when it attaches itself to a contact lens it can produce a bad eye infection that can be difficult to treat and may scar the eye. You do not want this type of eye infection…ever.
Acanthamoeba is also found in lakes, pools, and hot tub water—even when the water has been treated with chemicals such as chlorine. Speaking of chlorine, you don’t want this on your lenses because it can soak into the lens material and cause eye irritation.
When I was a board member of the American Optometric Association’s Contact Lens Section, we created a list of things that you should and should not do with contact lenses. This included removing lenses, including scleral lenses, before swimming or entering a hot tub. When showering, wait until you are finished to put on your scleral lenses.
However, if you have a compelling reason for wearing your sclerals—such as swimming during a triathlon—an argument can be made about the safety concerns of not wearing your lenses. In those cases, have a conversation with your doctor and find a compromise. In our practice, we have allowed patients with certain eye conditions who swim in triathlons to use water-tight goggles.
How should I clean my lenses?
Doctors have different opinions on this topic. Some love certain solutions and regimens over others. Although doctors’ opinions vary, there are some agreed-upon themes.
First, whichever solution you are using, always rub your lenses in the palm of your clean hands with a solution that is approved for gas-permeable lens materials. The rubbing step takes the deposits off the lenses. It’s like pre-rinsing your dishes before you place them in the dishwasher—the big chunks of food are removed and the dishwasher just needs to do a final clean. With scleral lenses, substances in tears attach to the lens surface. If not properly cleaned, these substances prevent the lenses from wetting properly. Sometimes, dry spots develop on the lenses that interfere with vision.
Second, follow the exact instructions included with the solution. One solution we love to use with scleral lenses contains peroxide. An example of this is Clear Care. The peroxide goes through a chemical reaction after it sits in the case (included with the solution bottle) for six hours. After six hours, the only things remaining are water and air.
If you don’t follow the instructions and the peroxide does not go through the chemical reaction, you are going to have a very bad day. Applying peroxide directly on the eyes is one of the most painful things you can experience. Luckily, it almost never results in permanent damage.
Another reason the chemical reaction doesn’t happen is that people forget to replace the case. The case needs to be replaced every time you buy another bottle of solution because the case is WHY the peroxide goes through the chemical reaction. The case is only effective for a certain number of reactions.
Sometimes, doctors prescribe two separate cleaning solutions for scleral lenses: a peroxide solution and a gas-permeable (GP) lens solution. These GP solutions are made to be used immediately without having to wait six hours. They are useful if you need to remove and clean your lenses during the day. Examples of these solutions are Unique pH, Boston, and Lobob.
How should I store my scleral lenses when not in use?
Many times, patients ask this question because they receive a new pair of lenses and want to keep the old pair as backup. This is a great strategy since keeping multiple pairs of new lenses can get pricey. Sometimes patients like to take a break from wearing contact lenses. Whatever the reason, it is important to keep your lenses clean and sterile.
A story that still pains me to this day was when I was practicing in a university medical center. An untrained staff member may have stored a sample lens in regular saline instead of a contact lens solution with antibacterial chemicals. We were about to place the lens on a patient’s eye when I noticed that something didn’t look right. Upon further inspection, we discovered the lens was covered in a murky fungus!
In order to prevent something like this from happening, some people might wonder why not store scleral lenses dry? While it could be done, there is a good reason for not doing it. When new lenses are made, a coating is applied to the surface that allows them to wet better. The coating—Tangible Hydra-PEG or Hydra-PEG—also makes the surfaces of the lenses much more resistant to deposits from proteins in the tears. The result is lenses that work better.
Now here’s the catch: if the surface of the lens dries out, the Hydra-PEG coating goes away. It can’t stand up to being dry for more than a few minutes. If this happens, it’s not the worst thing in the world. The lens surface will just go back to how it was before the Hydra-PEG coating was added.
If you decide to store your lenses wet, each contact lens solution has its own rules for the length of time you can store lenses. Peroxide solutions usually let you store lenses for seven days before needing to replace the liquid. Other solutions allow storage for up to one month. The most important thing to do is read and follow the instructions for your particular solution. You never want to end up with a lens that is coated in fungus!
Why do I need to use a preservative-free solution to fill my lenses?
Studies have shown that the solution that you fill your lenses with at the start of your day is the solution that stays there all day long. In other words, that solution sits on your eye all day long.
If you use a solution with a preservative, that preservative sits on the eye all day long. Preservatives are, by nature, not good for the eyes. A preservative works by being toxic to bacteria, fungus, and viruses. But for the same reason, they are toxic to the bad guys, they are also toxic to the good guys… your eyes. A preservative-free solution is the only type of solution that can sit on the eyes all day long.
How can you tell if a solution has preservatives? Anything that comes in a large bottle has to have preservatives. Solutions that come in single-dose packs or small droppers can be preservative-free. We recommend using AddiPak® or Nutrifill to fill your scleral lenses. Sometimes it takes a little bit of experimentation to find the exact solution that works best with your eyes.
Hopefully, the information provided will help you wear your scleral lenses with the greatest comfort and keep your eyes healthy. At Optique, we take time with each patient going over the do’s and don’ts for scleral lens wear. I tell my patients, “As long as you follow the rules, you are going to love your sclerals.” It is when people stray from the rules that they get into trouble.