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. (Learn More)
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. (Learn More) 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. (Learn More)
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. (Learn More)
Cataracts and Glaucoma: Are They Connected or a Coincidence?
There are several conditions that affect the eyes, especially in middle age and older adulthood. Two of the more infamous conditions are glaucoma and cataracts. If you are aging or have a family history of either of these issues, you may worry that your vision will get worse until you go blind. You may be concerned that, if you have one condition, you will develop the other. And you may worry about how these conditions are managed with modern medicine.
Cataracts This condition is a disease affecting the lens of the eye, leading to cloudiness or darkening of the lens, preventing light from filtering back to the retina. You may have trouble seeing because the world becomes fuzzier or colors become duller. You may have increasing problems seeing well at night, making night driving dangerous.
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, or other symptoms.
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.
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 such a normal procedure that it is an outpatient operation.
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. However, as mentioned, the surgery is performed often and is well understood.
While cataracts are one basic condition, 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.
There are two basic kinds of glaucoma.
- 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 involve poor blood flow to the eye.
- 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, seeing 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.
- 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.
- 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.
- 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 because their vision is blurry, 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.
- 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 age 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.
Signs and Symptoms
If you develop cataracts, the initial symptoms may seem like other conditions, especially refractive errors like farsightedness or nearsightedness. However, these will get worse faster than an existing refractive error, or they will take on other symptoms that are not associated with a refractive error you already have.
- 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 may also see whitening of the pupil of your eye, which is the forming cataract. Types of cataracts include:
- 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, and progress faster than other types of cataracts. They may also form as secondary cataracts after initial cataract surgery.
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:
- Sudden blurry vision.
- Severe eye pain.
- Nausea or feeling sick to your stomach.
- Rainbow rings, glares, or halos around lights.
Eye Treatments for Glaucoma and Cataracts Are Different
Cataract Treatment and Surgery
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.
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 constrains 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 miniscule 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 then the lens pieces will be removed. In some rare cases, often due to other medical conditions, the lens may be removed whole, but 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 lens 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:
- 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 goes not get better with over-the-counter painkillers.
- Vision loss.
- Secondary cataracts.
The most common condition after cataract surgery is secondary cataracts, but these are easily treated. Cataract surgery is considered medically important, so your health insurance, not your vision insurance, is likely to cover at least most of the cost.
Glaucoma Treatment: Medication First, Then Surgery Unlike cataracts, there are several medications that can slow glaucoma’s progress. These reduce pressure in the eye, greatly slowing the 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.
- 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 your eye.
- Carbonic anhydrase inhibitors to reduce how much fluid your eye produces.
- Miotics to make your pupil smaller (constrict), increasing how much fluid drains from your eye.
- Prostaglandin analogs to increase how much fluid drains from your eye.
Surgery for glaucoma is multifaceted, but aimed at reducing eye pressure. These include:
- 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.
Are They Linked?
Glaucoma and cataracts are two different conditions of the eye. They are more likely to occur in older adults, and one may result from surgery for the other, but they are otherwise not associated. One condition does not cause the other.
While treatment approaches have some similarities — they are both progressive conditions that need to be monitored and may require surgery — the procedures are different in both instances. 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.
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