If you’d prefer to wear contact lenses instead of glasses for improved vision, there are several types to choose from.
Both hard and soft contact lenses have their benefits and drawbacks. Which one is right for you may depend on your vision needs, lifestyle, and personal preferences.
If you’re considering hard contact lenses, read on to learn about the advantages and disadvantages of these lenses and how to use them safely.
The most commonly prescribed type of hard contact lenses are rigid gas-permeable (RGP) lenses. They’re more comfortable and safer to wear than earlier types of hard lenses, such as conventional polymethyl methacrylate (PMMA) lenses. PMMA lenses are seldom prescribed today.
RGP lenses are made from a flexible plastic material that typically includes silicone. This lightweight material allows oxygen to pass directly through the lens to reach your eye’s cornea.
Your cornea is the transparent, outermost layer of your eye. Your cornea refracts light and serves as your eye’s outermost lens. When your cornea doesn’t get enough oxygen, it can swell. This causes hazy or blurred vision, and other eye problems.
PMMA lenses did not allow oxygen to pass through the lens. The only way oxygen could reach the cornea was for tears to wash under the lens each time you blinked.
To allow tears to move under the lens, PMMA lenses were fairly small in size. Plus, there had to be a gap between the lens and the cornea. This made PMMA lenses uncomfortable to wear and made it easier for the lenses to pop out, especially when playing sports.
Because RGP lenses let oxygen pass through them, these lenses are larger than PMMA lenses, and cover more of your eye.
Also, the edges of RGP lenses fit more snugly against the surface of your eye. This makes them more comfortable to wear compared to the older variety. It also allows the lenses to stay on your eyes more securely.
Hard contact lenses are used to correct common vision issues known as refractive errors.
Refractive errors occur when the shape of your eye prevents incoming light from focusing correctly on the retina. The retina is a layer of light-sensitive tissue in the back of your eye.
There are several types of refractive errors that can be corrected by wearing RGP hard contact lenses, including:
Most of these conditions can also be corrected by soft contact lenses.
RGP hard contact lenses have several advantages when compared to soft contact lenses. Let’s look at these benefits in more detail:
- Sharp vision. One of the main differences between hard and soft contact lenses is crispness of vision. RGP hard contact lenses typically provide sharper, clearer vision than soft lenses.
- Deposit resistance. The tear film in your eyes contains proteins and lipids, which can get deposited onto contact lenses. Because RGP hard lenses aren’t made of materials that contain water (like soft contact lenses), these lenses are more resistant to protein and lipid buildup.
- Durability. If you don’t have a vision change and you take good care of your lenses, you may be able to keep one pair of hard contact lenses for 2 to 3 years.
- Less expensive. Because they last longer than soft lenses, hard contact lenses tend to be less expensive in the long run.
- Better option for astigmatism. People with astigmatism may benefit from RGP hard lenses called scleral lenses.
RGP hard contact lenses also have some drawbacks. Here’s a look at some common issues with these lenses.
- Period of adaptation. Hard contact lenses can take longer to get used to wearing than soft lenses. If you can’t tolerate wearing them consistently while you adapt to how they feel, they may not be a good choice for you.
- Regular use is key for comfort. If you don’t wear your hard contact lenses for several days, they may not feel comfortable right away when you put them in again. Your eyes usually need some time to adjust to them again in order for them to feel comfortable. This isn’t the case with soft contact lenses.
- They move more easily. Since hard lenses don’t mold to the shape of the eye like soft contact lenses do, they may dislodge and slip off the center of your eye more easily.
- Need good daily cleaning. Dust and debris can collect underneath hard contact lenses more easily than soft lenses. This can cause discomfort and raise the risk of corneal abrasion.
If you want your hard contact lenses to last as long as they should, it’s important to take good care of them. Taking care of your lenses will also lower the risk of an eye infection or scratches on your cornea.
- Daily cleaning. Daily cleaning of hard contact lenses is essential. It’s important to clean your contact lens case every day, too
- Don’t use tap water. The germs in tap water can stick to contact lenses. Instead, use cleaning solutions that are specially formulated for hard contact lenses.
- Use precautions when swimming or bathing. Because tap water can increase the risk of an eye infection, try to avoid wearing your contact lenses while swimming or bathing. Or, you can wear swimming goggles that keep the water from coming into contact with your lenses.
- Replace contact lens case regularly. Even though your hard contact lenses may last for several years, your lens case should be replaced every few months to avoid contamination with germs that can cause eye infections.
- Avoid saliva. Never clean your contact lenses with saliva. Your saliva contains bacteria that may harm your eyes.
- Clean your hands. Make sure your hands are clean every time you touch your contact lenses. Wash them thoroughly before putting your contact lenses into your eye or removing them.
- Don’t sleep in your lenses. This can increase your risk of getting an eye infection.
Rigid gas-permeable (RGP) lenses are the most common type of hard contact lenses prescribed today. They typically provide sharper, clearer vision than soft contact lenses. They also last longer and are often less expensive in the long run than soft lenses.
In addition, certain conditions, including astigmatism, may be corrected more efficiently by hard contact lenses.
However, it usually takes longer to adjust to wearing hard contact lenses and they may not be as comfortable as soft lenses. Talk with your eye doctor to find out what type of contact lenses are best suited for you and your vision needs.