RGP Lenses
Soft lenses are the most common type of contact lens, and the type most people are referring to when they speak about contact lenses, but there is another less well known type of contact lens called an RGP (Rigid Gas Permeable) or oxygen permeable lens. RGP contact lenses are rigid, but they shouldn’t be confused with old-style “hard” contact lenses, which are now obsolete. Old “hard” lenses did not allow oxygen to pass through them, and healthy eyes need plenty of oxygen.
What Is an RGP Lens?
RPG contact lenses are made from a firm plastic material. RGP lenses permit oxygen to pass directly through the lens to the eye so that it may “breathe.” Because they transmit oxygen these lenses are referred to as gas permeable.
Why Is Gas Permeability Important?
The eye needs regular amounts of oxygen in order to remain healthy, but a contact lens rests on the cornea, the clear front “window” of the eye forming a barrier between the cornea and the air. When the cornea does not get enough oxygen, it tends to swell and become cloudy which can lead to blurred vision or more serious complications. In addition to allowing oxygen to pass right through the lens, an RGP lens moves each time you blink, circulating oxygen-rich tears under the lens.
What are the differences between soft and RPG lenses?
1. One big difference between soft lenses and RGP lenses is their size: RGP lenses have a smaller diameter.
2. RPG lenses let more oxygen through than soft lenses.
3. RGPs can also provide better vision, durability, and deposit resistance than soft contact lenses.
4. RPGs can be easier to clean, and since they’re long lasting, they can be less expensive in the long term than soft lenses.
What are the Advantages of RGP Lenses?
1. RGP lenses are custom made and they can be designed to fit your eye exactly.
2. RGP lenses are excellent for astigmatism, a condition whereby the cornea is not perfectly round. Many people with astigmatism are unsatisfied with the vision they get with soft lenses. RGP lenses don’t bend, so they can give the astigmatismic cornea a more rounded shape, which provides crisp vision.
3. RGPs are extremely durable. Although you can break them (for instance, if you step on them), you can’t tear them easily, like soft lenses.
4. RGP lenses are also easy to handle. Unlike soft lenses, RGP lenses can usually be modified by your NVEC specialist in order to improve comfort. RGP lenses can usually be polished (by a professional) to get them very clean. None of this is possible with a soft lens.
5. RPG lenses don’t need to be taken out as frequently.They can be left in overnight and for several days at a time without being removed.
What Are the Disadvantages of RGP Lenses?
1. To achieve maximum comfort with RGPs, you need to wear them regularly (although not necessarily every day).
2. RGP lenses take a little longer to get used to. Many people beginning RGP lens wearers can feel the lens edge and find that feeling uncomfortable. However, the overwhelming majority of people who try RGP lenses adapt quite well to them within 2-3 weeks.
3. Some people experience “spectacle blur” with RGPs: when lenses are removed, vision is blurry, even while wearing glasses. This effect is temporary, but it can necessitate full-time RGP wear.
4. RGP lenses can “pop-out” of the eye more readily than a soft lens during sports activities, but this is rare.
Consult a NVEC RGP lens specialist to see if RPG lenses are a suitable for you.
New Vision Eye Clinic Ophthalmologists who specialize in RGP are:
For more information or to schedule an appointment with one of the above physicians, please call (8621) 6437 7445