What Does Toric Mean in Contact Lenses?

Medically Reviewed on 10/7/2021
what does toric mean in contact lenses
Toric contact lenses are designed to correct astigmatism, which is caused by abnormal curvature of the cornea. Learn about the pros and cons

Toric contact lenses are designed to correct astigmatism, which is caused by abnormal curvature of the cornea. Astigmatism is an ocular condition where the surface of the cornea is irregularly shaped. Because of this, the image formed over the retina is not sharp, causing blurred vision.

While standard contact lenses have a spherical surface, toric contact lenses have a geometric shape and have the ability to develop several focal lengths. Toric contact lenses are mostly prescribed for moderate corneal astigmatism (between 1-2 diopters).

What are the benefits of toric contact lenses?

Wearing a toric contact lens for astigmatism offers the following benefits:

  • Better field of vision than glasses which obstruct the peripheral field
  • Better fit over the cornea; hence, visual acuity is better than with glasses
  • Aesthetically pleasing
  • Less invasive compared with LASIK or surgical intervention
  • More flexible and therefore more comfortable than a rigid or hard lens
  • Better oxygen permeability to the cornea than a rigid lens (this is better for corneal health and viability in the long run)

Toric contact lenses have a different structure compared with lenses meant for myopia. They have a specific thicker zone (axis) that prevents them from rotating when they are in your eyes. This middle axis helps even out the irregularity over the corneal surface as seen in corneal astigmatism.

Do toric lenses correct all types of astigmatism?

Eyes are complex organs. The entire process of vision right from light falling over your corneas to the image being formed over the retina and being sent to the brain requires precise events to occur at precise angles. 

Moreover, in some people, astigmatism may be present in more than one axis. Correcting such compound astigmatism with a toric lens may not always be possible. Toric lenses, for example, will not help much if you have lenticular astigmatism (irregular lens surface).

Additionally, some individuals have very high-power astigmatism or progressive astigmatism, wherein choices in contact lenses get slimmer. Some individuals over 40 have presbyopia, and they may require glasses for reading even after wearing toric lenses because the lenses can be combined with either a myopic or hypermetropic power lens, but not both.

Are toric contact lenses worth it?

With the advances in ophthalmology, people with various refractive errors have multiple options to choose from. Each option (glasses, contact lens, surgery, and LASIK) comes with its pros and cons. If you do not want to try invasive procedures early on, you may give contact lenses a shot. 

However, people who want to go for LASIK must avoid using contact lenses for a long time because long-term use of contact lenses tends to thin out and weaken the cornea, making LASIK less effective and more complicated.

Keep in mind the following when wearing contact lenses:

  • Toric lenses are more expensive.
  • They need to be cleaned and disinfected daily. 
  • You should never sleep wearing the contact lens.
  • You should never use the contact lens for periods extending its expiry date.
  • You should never use the contact lens meant for someone else.

Make sure you get your contact lens from an experienced ophthalmologist. You may ask for a trial initially to see if the lens suits your eyes. In addition, if you use toric lenses, you should get your eyes checked annually.

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Medically Reviewed on 10/7/2021
References
https://www.aao.org/eye-health/glasses-contacts/contact-lens-102

https://www.uptodate.com/contents/overview-of-contact-lenses?search=toric%20contact%20lens&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1