Contact lenses are a welcome alternative for people who wear eyeglasses. They present freedom to people who do not wear eyeglasses. If you have an active lifestyle, this freedom can mean so much. This is more so if you do not like the effect of eyeglasses on your facial aesthetics, making contacts an option you would like to explore.
But while contacts appear similar to the untrained eye, some designs bring subtle differences. These differences are only subtle when you look at the lenses. But in terms of function, they significantly impact the lens. Because of the various eye conditions and their requirements, scientists have created two primary contact forms: traditional and specialty lenses.
Traditional contact lenses are lenses that correct myopia and hyperopia. The lenses sport simple designs featuring a single power across the entire surface. They have a standard size and often have standard materials. The most common type of conventional contact is made of silicon hydrogel, which falls under soft contact lens types.
These lenses are the same ones used for cosmetic or aesthetic purposes. Because they are soft and easy to fit, you can get these online from licensed dealers, as long as you have a recent prescription.
Specialty contacts are lenses that differ significantly in their design from conventional lenses. They are often designed for people with hard-to-fit conditions. These are conditions that may require variations in power within the same lens. Other conditions are complex and require larger diameters, while others need lenses that can maintain tears.
Some conditions are complex, requiring a particular type of lens that allows for complex prescriptions. Here are some of the hard-to-fit conditions that require specialty contact lenses:
Giant papillary conjunctivitis
These conditions all require their specific prescriptions and lens designs.
The most popular specialty contact lens is the scleral lens. This is much larger in diameter and is a rigid gas-permeable lens. Rigid gas-permeable lenses are stiffer and firmer than soft contact lenses.
Unlike standard-size lenses, scleral lenses rest on the sclera. The lens can thus vault over the cornea, forming a dam of tear underneath. These lenses work well for people with dry eyes and astigmatism.
Toric lenses are another type of contact lens that helps correct astigmatism. The lenses are made with varying powers on the same lens. Additionally, the lens is usually weighted at the bottom. It is designed to stay in the same position even when you blink. Because it has varying powers, the powers must be in the correct meridian for you to have a clear vision.
Orthokeratology or ortho-k lenses are special lenses designed for patients with progressive myopia. They may also work for patients who want to avoid wearing prescriptive eyewear during the day. You wear these lenses at night, letting them reshape the cornea while you sleep. You will have near-perfect vision throughout the day when you wake up.
For more on how specialty lenses differ from traditional contacts, visit Vision Source Grove Heights at our office in Houston, Texas. Call (346) 782-0288 to book an appointment today.