What are toric lenses?

Toric lenses are a special type of contact lens for people with astigmatism.

Astigmatism is an eye condition which causes problems with both long and short-sightedness, due to an irregularly-shaped cornea.

Toric lenses come in three types:

• Soft lenses – this is the most common form of toric contact lens, made from hydrogel. Soft lenses are more comfortable to wear and easier to adjust, but have a higher rate of infection;
• Rigid lenses – also known as gas permeable contact lenses, these tend to be more difficult to adjust but are much more durable;
• Hybrid lenses – an uncommon form of toric contact lens which combines a soft centre with a rigid outer part, balancing comfort and durability.

How do toric contact lenses work?

Toric contact lenses have a complex shape which corrects for the irregular shape of the cornea in people with astigmatism. This is the key difference with a regular contact lens, which is spherical.

The irregular shape of the toric lens means that correct fitting is essential. A regular contact lens is symmetrical on all sides so if it rotates while in the eye, the wearer’s vision is not affected. A toric lens, in contrast, has different sections with differing refractive power. These sections need to be aligned properly with the parts of the cornea being corrected. If the lens rotates while in the eye, the resulting misalignment can produce blurry vision.

What are the risks of toric contact lenses?

It’s important to make sure that you regularly change your contact lenses and do not wear them for longer than is recommended. The main risks of misuse are dry eyes and infection. Infection can lead to serious eye problems and further loss of vision. For more information on contact lens-related problems, click here.

What are the alternatives?

The main alternatives to toric lenses if you have astigmatism are:

• Scleral contact lenses – a special type of contact lens which is larger and offers greater comfort.
• Glasses – these offer a cheaper solution without the risk of infection, but may interfere with playing high-impact or contact sports
• Laser eye surgery – laser eye surgery is a permanent solution that involves correcting any irregularities in the cornea. Not all forms of astigmatism can be corrected with laser eye surgery.