Toric contact lens are used to correct both astigmatism and hyperopia or myopia. They contain two different curvatures or powers. Toric contact lens are dual contacts as they combine the effects of a spherical lens as well as cylindrical lens. They are increasingly being prescribed to people with astigmatism. These patients don’t have a perfectly round cornea. Also, they are prescribed to people who need help with their closer-up or far-away vision.
In few cases, the patients may have astigmatism in only one eye. For these patients, the ophthalmologist may prescribe a toric lens for one eye and a spherical lens for the other eye. There are two types of toric contact lenses available just like regular contact lenses. The only difference is that unlike regular contact lenses, torics are not spherically symmetrical.
Toric contac lenses are partitioned into specific “up” and “down” parts. Regardless of the eye movement, the toric contact lens must maintain its orientation. Otherwise, the visual acuity is affected. If the toric lenses are made slightly thicker and heavier at the bottom, they maintain their orientation perfectly. During blinking, the upper eyelid pushes the thicker zone downwards. This push allows the lens to rotate into the correct place.
Cost and Fitting
More amount of expertise and time is required for fitting toric lenses than in the case of spherical contact lens. Hence, they are more expensive. These toric lenses are marked with many orientation marks or tiny striations to assist in fitting. These marks or striations are invisible to the wearer.
RGP and Soft Torics
A wide range of formats are available in toric contact lenses as same as regular contacts. For correcting astigmatism, rigid gas permeable contact lenses were prescribed in the past. But now the scenario has changed. Now, the torics come in RGP or soft types. They are also available in disposable, frequent replacement and extended wear forms.
