Cataracts are an age-related condition that affects the eye’s natural lens. Astigmatism is a refractive error that occurs when the shape of the cornea or lens impacts how the eyes refract (bend) light. There are different treatments for each of these conditions, but in some cases, cataract surgery can correct astigmatism. But the surgery isn’t designed to correct the refractive error.
Your optometrist can review your options with you during a comprehensive eye exam. There are several ways your eye doctor can correct astigmatism during cataract surgery, but each has its advantages and disadvantages, which we’ll review further down.
What Is Astigmatism?
Astigmatism is a common error that occurs when the front part of the eye—known as the cornea—or the lens has an irregular shape instead of perfectly round. Many people have mild astigmatism, but it doesn’t require treatment unless it impacts your daily activities.
If the abnormal shape of the cornea or lens is too great, it can cause blurry vision, which can also worsen the symptoms of other refractive errors. Eyeglasses or contact lenses are often the first line of correction for astigmatism, but various refractive eye surgeries may also be an option depending on the individual.
Astigmatism Symptoms
Astigmatism symptoms vary between individuals, but some of the most common include:
- Blurry vision
- Needing to squint for clear vision
- Frequent headaches & eye strain
- Difficulty seeing at night
What Is a Cataract?
Cataracts are an age-related condition and the leading cause of vision loss in Canada. Nearly everyone develops cataracts as they age because the eye’s natural lenses harden and change over time.
Typically a person develops cataracts in both eyes, but they may notice the symptoms in one before the other. An increased glasses prescription or brighter lighting may help you see as a cataract develops. But these solutions don’t fix or prevent the condition from worsening.
Cataract Symptoms
Cataract symptoms typically get progressively worse as the cataract develops. These symptoms include:
- Trouble seeing at night or in low-light settings
- Glare and bright light sensitivity
- Seeing halos around lights
- Cloudy, blurry, or double vision
- Trouble identifying colours
What Is Cataract Surgery?
Cataract surgery is the only way to “cure” a cataract. It’s the most common surgical procedure performed in Canada and is safe and effective. Your eye doctor may recommend this surgery if your cataracts begin interfering with your ability to see, cause problems in your day-to-day life, or impact your quality of life.
During this procedure, an eye surgeon removes the clouded natural lens and replaces it with an artificial lens called an intraocular lens (IOL).
Does Cataract Surgery Correct Astigmatism?
Monofocal lenses were once the most common IOL and are still a practical option for many. These IOLs correct distance vision, meaning you may still need reading glasses or glasses that specifically correct astigmatism.
Technology is continuously improving, and there are now several ways your eye surgeon can correct astigmatism during cataract surgery.
Toric Intraocular Lenses (IOLs)
Toric IOL is the preferred method of correcting astigmatism during cataract surgery. A toric lens is designed to sit in the eye with a certain orientation, just like a toric contact lens.
The surgeon takes precise measurements of your eyes to determine where the toric IOL must sit for optimal correction, marking it on your eye. They then insert the new lens into the eye and line it up with the mark they made.
One possible drawback of this procedure is the potential for the IOL to shift during the eye’s recovery from surgery. When such a shift occurs, the effectiveness of the correction may decrease, depending on the extent of the lens displacement.
Limbal Relaxing Incisions
Limbal relaxing incisions (LRIs) are typically simple to perform alongside some cataract surgeries. Before cataract surgery, the eye surgeon takes precise measurements of the eye to determine the length and number of incisions necessary to reduce the curvature of the cornea.
Clear Corneal Incision (CCI)
A clear corneal incision (CCI) may be an option for those with astigmatism depending on the severity. This procedure usually consists of a single incision on the steep axis of the cornea. While it is a more affordable and simple way to correct astigmatism, it’s important to know that it may not be as effective as other treatments. Other options like toric IOLs or LRIs are designed to provide better results in those with more severe astigmatism.
Discuss Your Options with Your Eye Doctor
Although these eye conditions have different causes and symptoms, progress in medical science enables eye surgeons to treat both cataracts and astigmatism at the same time. But there isn’t a one-size answer to which treatment will work for you.
It may be the perfect time to ditch your astigmatism-correcting glasses if cataracts interfere with your daily life and it’s time for cataract surgery. Give us a call at Avenue Optometry & Vision Therapy to set up an appointment with one of our experienced eye doctors. They can review your options with you and come up with a treatment plan.
