Astigmatism occurs when the cornea (the clear front cover of the eye) is irregularly shaped. Instead of the cornea having a symmetrically round shape (like a baseball), it is shaped more like a football, with one meridian being significantly more curved than the meridian perpendicular to it. The irregular shape of the eye makes it hard for traditional contact lenses to fit and provide clear vision and therefore requires specialized contact lenses such as soft toric lenses or rigid gas permeable lenses (RGPs).
What are Toric Contact Lenses?
Toric contact lenses are designed to correct astigmatism and custom made to fit the eye of the patient. Rather than having a perfectly spherical surface like standard contact lenses, toric lenses have a more oblong shape made to accommodate the shape of the astigmatic eye. Toric lenses can be made of either soft or rigid gas permeable (RGP) lens material, however the soft toric lenses are more common.
Soft toric contact lenses are also designed in such a way that the lenses must stay aligned on the eye to maintain proper vision. Sometimes as the eye moves or blinks the lens can rotate considerably on the eye. If this rotation continues with a soft toric lens, a rigid gas permeable lens might be more effective. Rigid gas permeable lenses have a longer initial adjustment time, but once this has passed they are usually just as comfortable as soft contact lenses and they are often easier to care for.
Toric lenses are available in every wearing schedule from daily disposable to long-term wear. Due to the customization required, toric lenses tend to be more expensive and may take more laboratory time to make than traditional lenses.
If you have astigmatism, finding the right fit for your contact lenses is essential. Speak to your eye doctor today for a full assessment to determine which type of toric lenses will work best for you to help you see and feel your best.