The Differences Between Specialty Contact Lenses
Contact lenses have become an important alternative to eyeglasses since the 1970’s. That evolution began with the introduction of rigid gas permeable (RGP) lenses, a type of hard contact lens that enables oxygen to pass through the lens and reach the eye. RGP lenses are considered to be “hard” lenses because they retain their shape when on the user’s eye. Their hard design enables durability and easy care.
Soft contact lenses were the first “specialty” contact lens, though they are perhaps as common as RGP lenses today. When introduced to the United States market in 1971, these types of lenses quickly gained popularity for being more comfortable than their rigid predecessors. The soft design means the lenses feel less intrusive to the wearers’ eyes. It also means that soft lenses stay in place better than RGP lenses (a problem with hard lenses is that they can easily get knocked off the center of the eye) and are easier to adjust once in the eye.
By most measures, you wouldn’t regard rigid lenses and soft lenses as specialty lenses. These types of lenses are the standard in the contact lens market and are typically used as the first method for solving vision problems in patients who don’t wish to wear glasses. If a patient cannot achieve effective results through the use of standard hard or soft lenses, he or should would likely proceed to specialty lenses.
At Miami Contact Lens Institute, we are experts on a range of different specialty contact lens types. The first type is the scleral lens. Unlike most contact lenses, which sit right on the cornea, scleral lenses are designed to rest on the white of the eye, or the sclera. They then vault over the entire cornea, encasing that part of the eye in a reservoir of tears and preservative free saline. This design helps keep the eye hydrated, which reduces comfort problems. It also means that scleral lenses don’t have to match the curvature of the cornea exactly, an incredibly useful feature for patients with corneal irregularities. As such, these lenses are ideal for resolving issues with blurred or distorted vision.
Orthokeratology lenses are another specialty lens type we offer at Miami Contact Lens Institute. Patients wear this type of lens overnight, at which point it gently reshapes their cornea. The goal is to resolve vision problems related to irregular curvature of the cornea, including myopia (nearsightedness), hyperopia (farsightedness), and astigmatism. When the patient wakes up in the morning, they can remove the lenses and enjoy a day of clear vision. The cornea gradually reverts to its initial shape if the lens is not used regularly, which means ortho-K is not a permanent cure refractive errors. However, in providing the patient with the ability to see clearly during his or her waking hours—without glasses or contact lenses—ortho-K lenses have significant benefits. They are especially useful for athletes, pilots, firefighters, or other individuals who need to have clear vision without the encumbrance of glasses. They are most useful in children because they are also proven to slow down the progression of myopia which is becoming a worldwide epidemic.
Custom soft lenses are another type of specialty lens we offer. Some patients may think they are not good candidates for soft lenses because they have a high degree of astigmatism, myopia or hyperopia, because they have presbyopia or an unusual eye size. However, with the ability to customize soft lenses, any eye can be fit and there is essentially no limit in the parameters or curvature that can be chosen.
Finally, hybrid lenses are specialty lenses designed to incorporate the best features of both hard and soft lenses. Hard lenses retain their shape better than soft lenses and are less likely to lead to bacterial growth and eye infection. They also typically provide a slightly clearer vision. Soft lenses are more comfortable and more user-friendly. Hybrid lenses usually have a hard lens center with the edges of a soft lens. The resulting lens offers durability, sharp vision correction, comfort, and easy wear.
Which type of lens is right for you? Can you get by with standard soft lenses, or do you need something more specialized like a scleral lens or an ortho-K lens? At Miami Contact Lens Institute, we can help you find the right lens type and fit for you. Contact us today to schedule your first appointment.