As you get older, you may worry about developing glaucoma or cataracts, especially if you have a family history of these conditions. You may worry that if you get one, you are at greater risk of other chronic eye problems.
Fortunately, glaucoma and cataracts are not the same eye disease. They have different symptoms and treatments. Aside from a few risk factors, particularly age and eye trauma, they are not linked. One will not cause the other to develop, although they are often found at the same time in older adults.
This article compares cataracts and glaucoma, so you can learn more about both conditions, helping you understand why these conditions develop, what you may experience when these conditions develop, and how these progressive eye diseases are treated on a long-term basis. Both are very treatable. If untreated, their progression will lead to blindness.
It is important to work with optometrists and ophthalmologists to understand your symptoms, get a correct diagnosis, and start treatment.
Table of Contents
What are Cataracts?
Cataracts affect the lens of the eye, leading to cloudiness or darkening of the lens, preventing light from filtering back to the retina.
As you age or if your eye has suffered an illness or physical trauma, proteins in the lens can be damaged and begin to clump together. These clumps lead to spots that can cause fuzziness, blurriness, and other symptoms.
Older adults in the United States are the most likely to develop cataracts, although people who suffer head or eye trauma, a specific eye disease, or undergo a procedure like LASIK are also at risk of developing cataracts because of damage to the proteins in the lens.
Sometimes, a pregnant woman contracts an illness affecting her child in utero, or a genetic condition increases the risk of a baby being born with cataracts. Some illnesses, especially diabetes, increase the risk of developing cataracts.
There are no treatments to stop or prevent cataracts aside from surgery. However, you are not likely to need surgery immediately after you have been diagnosed with cataracts.
Most people who develop cataracts begin experiencing symptoms in their 40s or 50s and will not need surgery to improve seriously impaired vision until into their 60s. In the United States, over half of people in their 80s either have cataracts or have undergone surgery for cataracts. It is a routine surgery.
When you are diagnosed with cataracts in one eye, you will usually develop them in the other eye. If left untreated, cataracts can lead to blindness.
Types of Cataracts
These are types of cataracts:
- Nuclear cataracts, which form in the center and move outward
- Cortical cataracts, which form in streaks along the edges of the lens and move inward
- Congenital cataracts, which form in utero or just after birth
- Posterior capsular cataracts, which form at the bottom of the lens’s capsule, progress faster than other types of cataracts. They may also form as secondary cataracts after initial cataract surgery.
If you develop cataracts, the initial symptoms may seem like other conditions, especially refractive errors like farsightedness or nearsightedness. However, these symptoms will get worse faster than an existing refractive error, or you will experience other symptoms that are not associated with a refractive error you already have.
These are signs you may have cataracts:
- Faded or yellowing colors
- Blurry vision
- Needing updated prescription glasses or contact lenses more often
- Glare or halos around lights, especially at night
- Other difficulties with night vision
- Double vision in one eye
- Needing brighter light for normal activities like reading
You are most likely to experience cataracts as changes in your vision that seem like refractive errors like nearsightedness, farsightedness, or astigmatism. If you already suffer from a refractive error, you may experience sudden improvements in your vision and then worsening in your sight after that.
You may also see whitening of the pupil of your eye, which is the forming cataract.
What Is Glaucoma?
Glaucoma is considered a group of progressive eye diseases that lead to loss of nerve tissue and slow vision loss. When untreated, glaucoma will cause blindness. In fact, this series of conditions is the second-leading cause of blindness in the United States.
Types of Glaucoma
There are two basic kinds of glaucoma.
1. Primary open-angle glaucoma: This develops slowly without any symptoms or with very few symptoms. Until significant vision loss develops, most people are unaware they have glaucoma unless they get regular vision checkups that inspect their eye pressure.
At first, this condition affects side or peripheral vision, but this will advance to central vision loss as intraocular pressure (IOP) increases and more nerves in the eye are damaged. Both eyes will be affected by this vision loss over time.
This type of glaucoma may develop due to problems with the eye’s drainage system, which becomes inefficient with age, leading to slowly increased fluid buildup and therefore increased pressure. Another theory of the causes of this type involves poor blood flow to the eye.
2. Acute angle-closure glaucoma: This type of glaucoma is less common, but it appears abruptly with a sudden, rapid increase in eye pressure. Symptoms associated with this type include eye pain, redness in the eye, nausea from vision problems, halos or colored rings around lights, and blurry vision. It is an emergency condition in which vision can be lost quickly rather than progressively over years.
The most common cause of this type of glaucoma is trauma to the eye that causes the drainage angle in the eye formed by the cornea and iris to become blocked. It can be related to aging in some cases, leading to a chronic form of the condition that suddenly becomes a medical emergency; however, it is more often acute or caused suddenly.
3. Secondary glaucoma: This is the result of disease or an eye injury leading to abnormalities or damage. This is sometimes caused by eye surgery, like cataract surgery, but this is less likely.
4. Normal-tension or low-tension glaucoma: In this form of glaucoma, eye pressure remains low or in a normal range, but damage to the optic nerve occurs anyway. This is caused by an abnormally sensitive optic nerve, often caused by atherosclerosis, or a hardening of the arteries.
With blood flow issues, even normal eye pressure may be too much for the optic nerve, leading to nerve damage.
5. Congenital glaucoma: Children may be born with elevated eye pressure due to a defect in the drainage system, leading to nerve damage. They will have obvious symptoms like problems seeing, sensitivity to light, and excessive watering of the eyes. While these may not be noticeable immediately after birth, they will appear as normal infant and childhood development slows down due to the condition.
6. Pigmentary glaucoma: This occurs when the pigment from the iris sheds off and blocks the eye’s drainage system.
Pseudoexfoliation glaucoma: The eye produces extra material that sheds off the inner lining, blocking the meshwork.
Like cataracts, glaucoma is most often associated with age. People ages 60 and older are most likely to be impacted by both conditions.
Also, like cataracts, glaucoma cannot be prevented once it forms, but medications and surgery can treat the condition as it progresses. If it is diagnosed early, it can be successfully controlled.
Unfortunately, unlike cataracts, any loss of vision cannot be restored after surgery due to nerve damage.
For most types of glaucoma, there are few (if any) symptoms until the optic nerve becomes damaged. With regular eye exams, your optometrist will be able to follow the progress of any vision loss that shows up, along with your eye pressure, to determine the next steps in glaucoma treatment.
Without these regular checkups, the first sign of open-angle and secondary glaucoma is loss of spots of peripheral vision. This is similar to normal-tension glaucoma, although your optometrist may have a harder time diagnosing this condition.
Acute angle-closure glaucoma has sudden symptoms, indicating that a problem has rapidly developed. These include the following:
- Sudden blurry vision
- Severe eye pain
- Nausea or feeling sick to your stomach
- Rainbow rings, glares, or halos around lights
How Are Cataracts & Glaucoma Different?
Cataracts affect the lens of the eye, whereas glaucoma affects the optic nerve.
Each condition has different causes. Cataracts are caused by protein buildup on the lens, while glaucoma is caused by fluid buildup in the eye.
Glaucoma can result in permanent vision loss. While some vision loss occurs with cataracts, this is reversible with surgery that removes the cataract.
Cataracts are usually not considered a medical emergency, whereas glaucoma can be.
Similarities Between Cataracts & Glaucoma
Both cataracts and glaucoma can result in vision loss, particularly if they aren’t identified and treated early. Regular eye exams can help to detect both cataracts and glaucoma in their early stages, improving the patient’s long-term prognosis.
Diabetes is a risk factor for cataracts and glaucoma.
Do Cataracts & Glaucoma Affect Each Other?
Glaucoma and cataracts are two different conditions of the eye. You can have glaucoma and cataracts at the same time.
They are more likely to occur in older adults, and one may result from surgery for the other. Cataracts are more likely to form following glaucoma surgery.
If a cataract is very large, it may block the eye’s drainage system. This can lead to fluid buildup in the eye, increasing intraocular pressure and leading to glaucoma. Once the cataract is removed, eye pressure will usually decrease.
Eye Treatments for Glaucoma & Cataracts Are Different
Cataract Treatment & Surgery
Once you have received a diagnosis that you have cataracts, the treatment process will primarily involve monitoring the condition’s progress. You may need to make some lifestyle changes, like eating healthier or taking vitamin supplements, quitting smoking, and drinking less. These can all slow the progress of cataracts but will not stop the progress.
Eventually, when your sight limits your daily activities and makes it unsafe for you to perform normal functions like driving, even with corrective wear like glasses, your doctor will recommend surgery.
Cataract surgery is an outpatient procedure, and you will receive local anesthesia with eye drops. A minuscule incision will be made in your cornea and then another in the capsule containing the lens of your eye. The lens will be broken up, either with the help of lasers or just with a probe using a sound wave, and the lens pieces will be removed.
In some rare cases, often due to other medical conditions, the lens may be removed whole. However, this process has a longer recovery time due to greater impact on the eye.
Once the lens is removed, it will be replaced with an artificial lens called an intraocular lens (IOL). The most common version of this lens is a monofocal lens, but there are multifocal lenses for seeing all distances, toric lenses to simultaneously correct astigmatism, and other types of lenses that are more expensive and may not be covered by insurance.
Typically, recovery from cataract surgery requires several days of rest at home, and vision may not be restored for weeks or months after the procedure. Monofocal lenses mean that you will likely need reading glasses after the procedure, so you can focus on up-close activities.
Your ophthalmologist will work with you on the full list of activities to avoid and a timeline for when you can start returning to specific activities or hobbies, like reading and exercising.
There are a few risks from cataract surgery, but these are rare. They include the following:
- Infection in the eye
- Bleeding in the eye
- Swelling in the eye or increased intraocular pressure
- Swelling of the retina
- Detached retina
- Damage to other parts of the eye
- Pain that does not get better with over-the-counter painkillers
- Vision loss
- Secondary cataracts
The most common condition after cataract surgery is a secondary cataract, but this is easily treated. Cataract surgery is considered medically important, so your health insurance, not your vision insurance, is likely to cover most of the cost.
Glaucoma Treatment: Medication First, Then Surgery
Unlike cataracts, several medications can slow glaucoma’s progress. These reduce pressure in the eye, greatly slowing damage to the optic nerve.
You may get one or several prescriptions to treat glaucoma, depending on how high your eye pressure is and how rapidly the condition developed. The medications you use may change over time, as the disease progresses.
These medications include the following:
- Alpha agonists, which reduce the amount of fluid in the eyes and increase the amount of fluid that drains from the eye
- Beta-blockers to reduce the amount of fluid produced by the eye
- Carbonic anhydrase inhibitors to reduce how much fluid the eye produces
- Miotics to make your pupil smaller (constrict), increasing how much fluid drains from the eye
- Prostaglandin analogs to increase how much fluid drains from the eye
Surgery for glaucoma is multifaceted but aimed at reducing eye pressure.
Laser surgery: The laser-assisted procedure is called laser trabeculoplasty, which helps drain fluid with a high-energy laser beam aimed at the trabecular meshwork. This may be more temporary than other procedures. It may need to be repeated in the future, or another approach to surgery may be needed.
Acute angle-closure glaucoma is a medical emergency, needing immediate surgery called peripheral iridotomy. This is a laser surgery that creates a small hole in the iris, allowing fluid to drain freely into the front chamber of the eye, where it can be removed more easily.
Conventional surgery: This is a trabeculectomy, a filtering microsurgery that creates a drainage flap allowing fluid to percolate out into the rest of the vascular system.
Drainage implants: This is for adults with uncontrolled glaucoma, secondary glaucoma, or children with glaucoma. A silicone tube inserted into the eye directs the draining fluids out of the eye, relieving pressure.
Can You Have Cataract & Glaucoma Surgery at the Same Time?
You may find yourself with both diagnoses. That means you may use eye drops to treat your glaucoma, while your cataracts are monitored for years until they need surgery to restore your vision.
Generally, you can have both surgeries at the same time. Your ophthalmologist will assess whether this is appropriate for your situation.
While treatment approaches have some similarities — they are both progressive conditions that need to be monitored and may require surgery — the procedures are different for each condition.
Glaucoma & Cataracts FAQs
Which is worse: glaucoma or cataracts?
Glaucoma is sometimes considered more serious since it can be acute and require emergency medical attention. Vision loss from glaucoma might also be permanent, whereas vision loss from cataracts is generally reversible. Vision is often fully restored once the cataract is removed.
Neither condition is worse since it depends on the specifics of each person’s situation.
Can cataracts be mistaken for glaucoma?
It’s not likely. Cataracts are sometimes misdiagnosed as presbyopia. Glaucoma is sometimes misdiagnosed as a different type of optic nerve issue.
What are the symptoms of cataracts and glaucoma?
Cataract symptoms include clouded or blurry vision, halos around lights, poor night vision, vision changes, and colors appearing duller. Glaucoma symptoms include eye pain or pressure, nausea, vomiting, blurry vision, headaches, and eye redness.
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