Which type of contact lenses are better?

Dear Reader, 

It’s clear you’ve done your research into contact lenses—your eyes will thank you! Rest assured that both one-year and disposable contacts allow adequate oxygen to your eyes. However, correct usage of contacts, like being aware of how long they stay in your eyes, is an important factor involved in keeping your eyes healthy.  

What types of contacts are available? 

There are two common types of contacts: disposable soft contacts and one-year (sometimes two-year) hard contacts. Disposable contacts are more popular nowadays because of the comfort they provide. Disposable contacts can be made of traditional hydrogels, which are made of water-based materials, or silicone hydrogels, which are made with silicone-based materials. Different disposable contacts need to be disposed of at different times. So, if you’re using disposable contacts, be aware of the type you’re using and the different periods of use such as daily, weekly, biweekly, or monthly.  

One-year contacts are known as rigid gas permeable (RGP) lenses, and they’re made of hard plastic material. They are usually preferred by people with high prescriptions, high astigmatism, or irregular shapes in the cornea. 

Do one-year contacts allow less oxygen in than disposable contacts? 

You might be happy to learn that both one-year and disposable contacts allow a healthy amount of oxygen into your eyes when worn as recommended. The hard plastic material in one-year contacts allows oxygen to pass through (as indicated by the name “rigid gas permeable”). RGP technology has helped to prevent many of the oxygen-related problems that come along with prolonged wearing of contacts.  

Among disposable contacts, silicone hydrogel lenses are generally better at allowing oxygen through than traditional hydrogel lenses. This is because traditional hydrogel lenses depend on their water content to allow oxygen to pass through the lenses. In contrast, the silicone-based material in silicone hydrogel lenses is good at letting oxygen in and isn’t water-dependent.  

That said, extended use of contacts can prevent sufficient oxygen from reaching your eyes and could lead to a condition called cornea hypoxia. This can lead to blurry vision caused by corneal swelling or warping. Corneal neovascularization, which may be the condition you referenced, is also a potential outcome of cornea hypoxia. Corneal neovascularization occurs when blood vessels extend into new areas of your cornea, leading to permanent vision damage in more serious stages.  

Is there a preferred water content for contacts? 

Unfortunately, there’s no clear gold standard for water content in contacts. One main reason is that the level of lens hydration depends on multiple factors, including body temperature, your  tear production, and how hard you blink. Therefore, you may need to test your contacts out or consider discussing your concerns with a health care provider to determine what water content works best for you.  

The water in traditional hydrogel lenses brings oxygen to the eyes and helps the carbon dioxide your cornea produces go out. Sufficient water content is also important for keeping the lenses hydrated, so they make you feel comfortable and do their job in helping you see. One caveat is that higher water content may make the lenses easier to break and more difficult to handle. Water content isn’t as relevant for silicone-based lenses.  

Wearing contacts may also cause dry eye problems by disrupting the structure and activities of your tear film and adding friction to your eyes. Reducing screen time, using a humidifier, staying hydrated, and using artificial tear eye drops—obtained over the counter or with a prescription—can help combat dry eye. 

How long can contacts stay in your eyes? 

Depending on what kind of lens you use, contacts can stay in your eyes for about 12-16 hours. One-year contacts can stay in your eyes for 12 hours. Disposable contacts are usually safe to stay in your eye for up to 16 hours.  

Taking your contacts out at night is important for making sure your eyes get sufficient oxygen. Therefore, no matter what type of contacts you wear, it’s generally recommended to give your eyes a break after wearing contacts for a long time. You might consider switching to glasses when contacts give you discomfort or after you’ve worn them for more than the recommended length.  

Why do you feel more uncomfortable when wearing glasses compared to contacts? 

Discomfort with glasses often indicates that something is wrong. One possible reason is eye strain, which can cause fatigue and blurred vision, among other symptoms. Given that you’re working so hard during reading periods, eye strain might result from focusing for a long time, bad lighting in your environment, and distance from your screen. Incorrect prescriptions also contribute to discomfort with glasses. Finally, switching between glasses and contacts may cause vision problems, but further research is required to confirm this connection. 

Overall, to find the contacts that are the most suitable and comfortable for you, consider speaking with a health care provider to discuss your options and experiences with what you’ve tried so far.  

Hindsight doesn’t have to be 20/20 after all! Good luck!