Glaucoma is a group of eye disorders that cause damage to the optic nerve. Learn more about glaucoma symptoms, causes, types, and treatment options.


Close to 8 million people around the world live with glaucoma, including more than 3 million people in the United States. The eye disease is one of the leading causes of blindness worldwide, with nearly 10 percent of affected people experiencing blindness in both eyes due to the damage it causes to the optic nerve. Each eye has its own optic nerve, each consisting of a bundle of more than a million nerve fibers. These nerves relay visual messages from your eye to your brain to help you see.

Learn more about glaucoma, including its symptoms, causes, and risk factors. Find out how it’s diagnosed and treated and discover ways to help prevent glaucoma and support your eye and vision health now and in the future.

What is glaucoma?

mature woman sitting on an exam table while a doctor examines her eyes for glaucoma

Glaucoma is a group of eye disorders that cause progressive damage to the optic nerve. This damage can result in the loss of retinal ganglion cells (RGCs), which can lead to gradual but permanent vision loss.

RGCs are neurons (nerve cells) found on the ganglion cell layer, the inner surface of the retina. (The retina is the thin, light-sensitive layer of tissue at the back of the eye.) RGCs collect visual information from the eyes and send it to the brain for processing. Blind spots and sometimes complete blindness may occur as a result of widespread damage to these nerve fibers.

Glaucoma ranks second among the most common causes of blindness worldwide and in the U.S. It trails only cataracts, an eye disorder that causes vision loss due to clouding of the lens of the eye. In the U.S., glaucoma is the leading cause of blindness among Black and Hispanic people.

Although people of any age can develop glaucoma, it occurs six times more often in those over the age of 60. But only half of the people affected by glaucoma know they have it. This may be because optic nerve damage occurs gradually. Vision deficits may go unnoticed until extensive damage has taken place.

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What are the signs and symptoms of glaucoma?

Glaucoma symptoms may appear gradually over time. Eventually, people can start to develop small blind spots in their peripheral (side) vision, although these vision deficits may not be apparent until widespread damage to the optic nerve has occurred. When left untreated, optic nerve damage can lead to blindness.

Glaucoma symptoms may vary, depending on the type of glaucoma someone has (see below). In general, the various types can cause:

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What causes glaucoma?

There are two general categories of glaucoma. Primary glaucoma is not the result of another health issue. Secondary glaucoma is caused by another condition.

Although the exact cause of primary glaucoma remains unknown, experts theorize that most (but not all) cases result from optic nerve damage caused by high intraocular pressure. This is a measure of the pressure exerted by the fluid inside the eye. The cause of secondary glaucoma can vary, depending on the type (see below).

Common causes of secondary glaucoma include:

  • Large cataracts
  • Cataract surgery
  • Eye infection
  • Eye inflammation
  • Eye tumors
  • Medications such as steroids

These issues can prevent eye fluids from draining properly, which raises eye pressure and damages the optic nerve.

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What are risk factors for glaucoma?

People over the age of 60 are at higher risk for all glaucoma types, which may be due in part to the continual loss of RGCs that occurs as you get older. People of African descent experience higher rates of a type of glaucoma called open-angle glaucoma. Another type called closed-angle glaucoma occurs more often in people assigned female at birth (AFAB) and in those of Inuit or Asian descent. Rates of normal-tension glaucoma are highest among people of Japanese descent. (See more on the different types of glaucoma below.)

Other risk factors include:

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What are the types of glaucoma?

There are several adult and childhood forms of glaucoma. These are typically classified as primary or secondary, depending on the causes.

Primary glaucomas

These aren’t caused by another health condition. In fact, their causes are unknown.

Primary open-angle glaucoma (POAG)

Primary open-angle glaucoma (POAG) is the most common type of glaucoma. Worldwide, around 74 percent of people living with glaucoma experience this type. In the U.S, around 80 to 90 percent of people with the eye disorder experience POAG.

The eye’s internal drainage system (also called the anterior chamber angle) ordinarily allows fluids to drain from the eye as new fluid is added. This fluid is known as aqueous humor. The result is the maintenance of stable pressure in the eye.

Drainage occurs where the cornea (the outermost, clear layer of the eye) and the iris (the colored part of the eye) converge, at a spot known as the drainage angle. With POAG, the drainage angle of the eye doesn’t allow for sufficient drainage.

The tissues located at the drainage angle are known as the trabecular meshwork. The trabecular meshwork is like a one-way valve, which opens to allow eye fluids to circulate and drain out of the front of the eye. It consists of a group of tiny canals made of spongy tissue through which most fluids drain out of the eye and into nearby blood vessels.

Over time, the eye’s drainage canals become clogged. Aqueous humor continues to be produced at a normal rate but it drains more slowly. As a result, intraocular pressure goes up, raising the risk of glaucoma.

The main type of vision impairment that occurs with POAG is peripheral or side vision loss (also called narrowed or tunnel vision). POAG tends to develop slowly over months or years. As such, vision loss and other glaucoma symptoms may not be noticed for a long time. Blindness may eventually result from extensive damage to the optic nerve.

Primary closed-angle glaucoma (PCAG)

This is also referred to as angle-closure, narrow-angle, or acute glaucoma. With primary closed-angle glaucoma, the angle between the iris and cornea becomes too narrow. The outer edge of the iris bunches up, which blocks or covers the eye’s drainage canals.

This can occur when the pupil dilates (expands) too fast or too much, such as when you first enter a dark room. In general, PCAG can cause symptoms such as blurry vision, eye pain, headaches, nausea, and rainbow-colored halos around lights at night.

PCAG can come in two forms:

Acute: With this PCAG type, the drainage angle causes sudden and complete blockage of the eye’s drainage canals. This is referred to as an acute angle-closure glaucoma attack. It causes a rapid increase in intraocular pressure, which requires emergency medical care to prevent blindness. Left untreated, this rapid rise in eye pressure can cause blindness within hours.

Call 911 or get emergency medical care if you experience an acute angle-closure glaucoma attack. Warning signs may include a sudden onset of intense eye pain (usually in one eye), blurry vision, and eye redness. This attack may also cause a severe headache accompanied by blurred vision and the appearance of rainbow-colored halos around bright lights.

Nausea and vomiting may also occur. Because these glaucoma symptoms can mimic those that occur with migraines, it may be mistaken for a migraine flare-up.

Chronic: With chronic PCAG, the eye’s drainage angle causes a slow but progressive obstruction of the eye’s drainage canals. As such, eye pressure rises slowly, much like open-angle glaucoma.

Chronic PCAG may cause symptoms such as blurry vision, eye discomfort, redness, or a headache that improves with sleep. For some, glaucoma symptoms may not be noticed until the damage becomes extensive.

Normal-tension glaucoma (NTG)

Also referred to as normal-pressure or low-tension glaucoma, this is a type of open-angle glaucoma that damages the optic nerve without causing intraocular pressure to exceed the normal range of 12 to 21 millimeters of mercury (mm Hg). Nevertheless, eye pressure still causes damage to the optic nerve.

The exact cause of NTG isn’t known. But it’s believed that certain factors that affect blood flow to the optic nerve and that compromise the structural integrity of the optic nerve tissue may play a role. These risk factors include:

  • Age older than 60
  • Being assigned female at birth
  • Family history of NTG among first-degree blood relatives (such as a parent or sibling)
  • History of higher than average eye pressures
  • Thin cornea
  • Inheriting genes such as optineurin (OPTN), TANK binding kinase (TBK1), and myocilin (MYOC)
  • Dementia types such as frontotemporal dementia and Alzheimer’s disease
  • Hypertension (high blood pressure)
  • Migraines
  • Nocturnal hypotension (low blood pressure during sleep)
  • Obstructive sleep apnea (a sleep disorder that occurs when the throat muscles relax and block the airway, disrupting breathing for short periods during sleep and causing other symptoms such as snoring and excessive daytime sleepiness)
  • Raynaud’s phenomenon (a condition that limits blood flow to the small blood vessels of the fingers, toes, and sometimes the ear lobes, lips, and nose, causing symptoms such as skin color changes, cold skin, and a tingling sensation)
  • Carotid artery disease (also called carotid artery stenosis, this condition causes narrowing or blockage of the carotid arteries, which are the main blood vessels that carry blood to your brain, head, and face)

Experts aren’t sure whether NTG is a separate eye disease or is part of the spectrum of POAG, although some features of NTG stand out. For instance, NTG often impairs central vision (the field of view when looking straight ahead). Hemorrhages (blood loss due to damaged blood vessels) also occur more often in the small blood vessels of the optic nerve with NTG.

Like POAG, symptoms may not be noticeable in the early course of the disease. Central vision gradually blurs, with peripheral vision loss also occurring as the condition worsens.

Childhood glaucoma

Children can develop glaucoma when the drainage system in their eyes doesn't develop properly. The eyes of children with childhood glaucoma may:

  • Appear cloudy, red, and/or enlarged (one or both eyes)
  • Be sensitive to light
  • Produce excess tears

Childhood (or pediatric) glaucomas are classified based on when the condition develops. It’s diagnosed as primary congenital glaucoma (PCG) when the eye condition is present at birth or develops before 3 years old.

PCG is rare, affecting only around 1 in 10,000 babies born in the U.S. The condition is diagnosed as juvenile open-angle glaucoma when it develops after 3 years old.

The development of PCG has been associated with several genes. These include cytochrome P450 family 1 subfamily B member 1 (CYP1B1) and latent transforming growth factor-beta binding protein 2 (LTBP2). Structural defects in the trabecular meshwork and the aqueous humor drainage pathways have been tied to CYP1B1 gene mutations.

The LTBP2 protein can be found in the eye’s trabecular meshwork, helping to produce aqueous humor, regulate intraocular pressure, and develop zonules (the thread-like fibers that hold the lens of the eye in place). LTBP2 gene mutations may affect these processes.

Secondary glaucomas

In some cases, glaucoma may be due to another condition. For instance, childhood glaucoma may stem from other causes such as eye inflammation or trauma, cataract removal, or treatment with steroids. Other examples of secondary glaucoma include:

Exfoliative glaucoma

Also called pseudoexfoliation or pseudoexfoliative glaucoma (PEG), this is most often a type of open-angle glaucoma that occurs in some people with pseudoexfoliation syndrome (PEX). In rare instances, it may also be associated with closed-angle glaucoma. It’s the most common form of secondary open-angle glaucoma in the world.

PEX causes white, flaky protein deposits to build up in the drainage system and other parts of the eye such as the iris and lens. (The lens is the clear, curved part of the eye that sits behind the iris and helps to focus light on the retina to aid with vision. The retina is the light-sensitive tissue layer at the back of the eye.) Cataracts and glaucoma are among the eye complications associated with PEX.

Exfoliative glaucoma occurs more often in certain racial and ethnic groups, including people of Russian, Nordic, Mediterranean, and Indian descent. Mutations associated with the fibulin-5 (FBLN5) gene have also been tied to a higher risk of PEG.

This secondary glaucoma tends to cause higher intraocular pressure and progress faster than POAG. Episodes of high eye pressure occur more frequently with PEG. Intraocular pressure also fluctuates more often than with other types of glaucoma.

Neovascular glaucoma (NVG)

This secondary glaucoma occurs with disorders involving retinal ischemia (insufficient blood flow to the retina). The main conditions that involve retinal ischemia include:

  • Diabetic retinopathy (a type of diabetic eye disease)
  • Central retinal vein occlusion (blockage of the main vein where blood flows through the retina, causing blood and excess fluid to collect in the part of the retina that controls central vision called the macula)
  • Ocular ischemic syndrome (a condition that occurs when plaque builds up in the neck’s carotid artery, restricting or blocking blood flow to one or both eyes)

Retinal ischemia triggers the release of vascular endothelial growth factor (VEGF), a substance that promotes the growth of new blood vessels. These new blood vessels leak, grow in the wrong place in the eye (such as over the eye’s trabecular meshwork), and cause bleeding, inflammation, and scarring. As a result, eye pressure rises, damaging the optic nerve. NVG can cause glaucoma symptoms such as eye pain, discomfort, and redness, along with vision loss.

Pigmentary glaucoma

Also called pigment dispersion glaucoma (PDG), this glaucoma type occurs as a result of pigment dispersion syndrome (PDS). The syndrome causes the pigment from the back of the iris to flake off when friction occurs between the outer layers of the iris and the lens and zonules. These pigment flakes become trapped in the eye’s drainage canals, resulting in increased eye pressure and damage to the optic nerve.

Physical activities like jogging or running can cause pigment flaking in people with the syndrome. Eye pressure temporarily spikes but usually goes back down. These eye pressure spikes can lead to glaucoma symptoms such as blurry vision and seeing rainbow-colored halos around lights.

PDS occurs more often in young, white people assigned male at birth with myopia (nearsightedness). Pigment dispersion occurs less often as people get older, although the risk for glaucoma can persist.

Traumatic glaucoma

Traumatic glaucoma can result from injuries that either penetrate the eye or bruise the eye without penetrating it (referred to as a blunt trauma), such as from a blow to the head (concussion). Symptoms vary depending on the injury sustained.

Traumatic injuries can cause bleeding. Blood and other debris can pool and clog the eye’s drainage canals. Eye pressure rises as a result, damaging the optic nerve.

In some cases, excess scarring that results from damage to the drainage canals can also block blood flow, causing angle-recession glaucoma. This is a type of open-angle glaucoma that can occur years after getting injured.

Conditions such as an eye infection, myopia, and prior eye surgery or injury can make the eyes more prone to eye trauma, which can lead to glaucoma.

Uveitic glaucoma

Uveitic glaucoma affects about 20 percent of people with uveitis, a condition that causes the middle layer of the eye called the uvea to become inflamed. Uveitis can cause symptoms such as blurry vision, pain, redness, sensitivity to light, and eye floaters. (Floaters are clumps of cells that cause small dark shapes to move across your vision.)

Exactly how uveitis causes glaucoma isn’t clear, but some experts believe that inflammation and scar tissue that forms in the middle layers of the eye damages or blocks the eye’s drainage canals. This can raise eye pressure and damage the optic nerve.

Corticosteroids (also called glucocorticoids or steroids) used to treat uveitis can also increase intraocular pressure. This can cause or make uveitic glaucoma worse.

Some disorders that cause uveitis (such as Fuch’s heterochromic uveitis, herpetic uveitis, and Posner-Schlossman syndrome) often cause uveitic glaucoma in one eye only. Other associated disorders (such as the inflammatory disease sarcoidosis and various types of arthritis like ankylosing spondylitis and juvenile idiopathic arthritis) tend to affect both eyes.

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What are the stages of glaucoma?

Multiple glaucoma staging systems have been developed over the years. Although no particular system is considered the gold standard, they share certain similarities. Generally speaking, higher stages indicate more structural damage to the optic nerve and subsequent vision loss.

International Classification of Diseases (ICD) for glaucoma

One of the most widely used staging systems is the International Classification of Diseases (ICD), developed by the World Health Organization (WHO). Although ICD criteria require optic nerve damage consistent with glaucoma to be present for healthcare providers (HCPs) to make a diagnosis, disease severity is based on the results of a visual field test.

This test measures how wide of an area (up, down, and to the sides) you can see when you look straight ahead without moving your head. It also measures how sensitive your vision is in various parts of your visual field, which is the entire area your eyes can see.

The WHO’s classification system divides the entire visual field into three regions to help determine glaucoma severity:

  • Superior hemifield, which is the top half of the visual field
  • Inferior hemifield, which is the bottom half of the visual field
  • Central 5 degrees of fixation, which involves gazing at a point straight ahead (your central field of vision) to determine if there are any visual abnormalities within a 5- degree range of that point

Based on the results, the ICD system stages glaucoma as:

  • Mild glaucoma: Normal visual function, meaning no vision problems are detected
  • Moderate glaucoma: Visual abnormalities are detected in one hemifield, but not within 5 degrees of central fixation
  • Advanced glaucoma: Visual abnormalities detected in both hemifields and/or within 5 degrees of central fixation

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How is glaucoma diagnosed?

If glaucoma is suspected, your HCP will conduct a comprehensive eye exam to diagnose or rule it out. This exam often involves:

Measuring eye pressure

Tonometry is a test that measures intraocular pressure. It can help detect changes that occur with glaucoma. In general, readings above 21 mm Hg are considered high intraocular pressure.

Multiple forms of tonometry can be used. With most techniques, eye pressure is measured by determining the force needed to gently flatten a fixed area of the cornea. One such technique is air-puff tonometry. Also called no-contact tonometry, a rapid puff of air is used to slightly flatten the cornea. If your test results are abnormal, other tonometry methods may also be employed.

Applanation (or Goldmann) tonometry provides the most accurate intraocular pressure readings. Considered the gold standard, this method involves the use of a flat-tipped probe to gently applanate (flatten) a section of the cornea.

Other forms of tonometry use different instruments, although these also involve placing a small amount of pressure against the eye. For instance, a handheld device that resembles a large marker (called the Tono-Pen) may be used to measure intraocular pressure by gently touching the eye.

Another handheld device called the iCare tonometer instantly records eye pressure after gently tapping the surface of the cornea. This method may be easier to use in children and other people who have a hard time with other contact forms of tonometry.

Assessing the optic nerve

Although measuring eye pressure often plays a key role in diagnosing glaucoma, tonometry test results aren’t enough to confirm the diagnosis. That’s because a third to half of people with the eye disease have eye pressures within the normal range.

In some cases, glaucoma isn’t the cause of high intraocular pressure. Moreover, many people with high intraocular pressure never develop glaucoma.

As such, your HCP will closely examine your eye to look for changes in the optic nerve and other parts of your eye that may have been caused by glaucoma. This may involve one or more of the following tests:

Slit-lamp exam and fundoscopy

During this exam, your chin rests on a soft pad to hold your head in place. Your HCP, meanwhile, uses a microscope called a slit-lamp and an ophthalmoscope (a small, handheld device equipped with magnifying lenses and a light) to take a close look at the back part of your eye (called the fundus). Your HCP will look for changes in the shape and color of your optic nerve and retina, including the macula (the part of the retina responsible for central vision).

Optical coherence tomography

Another way to assess the optic nerve (and detect and monitor glaucoma) is through optical coherence tomography (OCT). The test is similar to an ultrasound, but OCT uses light instead of sound waves to scan and create high-resolution images of your eyes while you rest your head on a chin rest. OCT may be performed up to six times a year to monitor any changes to your optic nerve and other parts of the eye (such as the macula).

Checking peripheral vision

Central vision is what you see straight ahead, while peripheral vision is everything you see that isn’t in your central vision. It’s what you see up and down and out of each side of your eye when your head is still.

Your HCP will conduct a visual field test to check your peripheral vision. This is often done with the help of a machine that tracks your ability to see small dots of light that move through the various visual field areas. This creates a map of your vision to help determine if, where, and how the optic nerve has been damaged.

Examining the eye’s drainage channels

Your HCP will want to examine the drainage channels in your eyes, also called its anterior chamber angle, which consists of the trabecular meshwork. The test to do so is called gonioscopy. This involves the use of a special handheld contact lens placed on the eye and a slit-lamp to illuminate the angle between the iris and the cornea.

The contact lens is equipped with a mirror that helps your HCP look at the inside of your eye from various angles. By examining your eye’s drainage channels, your HCP may be able to determine if you have open-angle or closed-angle glaucoma.

Measuring corneal thickness

Although several methods and devices can be used to measure corneal thickness (clinically referred to as central cornea thickness, or CCT), pachymetry is the most widely used approach.

Ultrasound pachymetry remains the gold standard for measuring CCT. It involves using a handheld device equipped with an ultrasonic probe that measures thickness when placed on the eye. The accuracy of the readings hinge on precise placement of the probe.

Newer techniques can create precise maps of the thickness and curvature of the cornea. These include high-resolution ultrasonography, optical coherence tomography (OCT), scanning-slit technology, and Scheimpflug-based anterior segment imaging.

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How is glaucoma treated?

Woman wearing a hospital gown and cap lying on a hospital bed during surgery to correct glaucoma

Because there’s currently no way to reverse optic nerve damage, no glaucoma treatments can restore vision loss. Lifelong treatment is usually required to help prevent further vision loss. That said, advances in glaucoma treatment offer hope that one day vision loss may be reversed.

Medications for glaucoma

Eye drops are usually the first line of treatment, although an oral medication may be considered if drops don’t sufficiently lower eye pressure. For people who require more than types of medication, combination drugs are also available.

Alpha-adrenergic agonists for glaucoma

These medications help decrease fluid production in the eyes while increasing fluid drainage. Examples of alpha-adrenergic drops used to treat glaucoma include apraclonidine and brimonidine.

Side effects may include:

Beta-blockers for glaucoma

These help reduce eye fluid production, which helps lower eye pressure. Examples of beta-blocker drops used to treat glaucoma include betaxolol and timolol.

Side effects may include fatigue and impotence. They can also slow your heart rate, lower blood pressure, and make breathing problems worse.

Carbonic anhydrase inhibitors for glaucoma

These reduce the rate of eye fluid production. Examples include brinzolamide and dorzolamide. These may be prescribed as eye drops or as pills taken orally.

Side effects may include frequent urination, metallic taste, and tingling in the fingers and toes. Other side effects include depression, kidney stones, and upset stomach.

Miotics (cholinergics) for glaucoma

These eye drops cause the pupil to constrict (shrink or become smaller), which helps open the blocked drainage angle. Miotics such as pilocarpine, once used more prevalently, are no longer commonly prescribed due to the need for frequent use each day and the potential for side effects such as:

  • Blurred or dim vision
  • Eye redness and pain
  • Headache
  • Nearsightedness (also called myopia, which causes far-away objects to appear blurry, although close-up vision remains intact)
  • Pupil narrowing
  • Retinal detachment (an emergency situation in which the retina pulls away from the tissues that support it)

Prostaglandin analogs

Prostaglandin analogs or agonists (PGAs) help lower intraocular pressure by increasing drainage of eye fluids. Most are eye drops, with the exception of a dissolvable bimatoprost implant, which releases medicine over a 90-day period.

PGAs enhance the activity of the prostaglandin hormone, which helps regulate the outflow of aqueous humor. Examples include bimatoprost, latanoprost, omidenepag, and travoprost. Tafluprost is a preservative-free PGA.

Side effects may include:

  • Darkening of the iris and the skin on the eyelid
  • Droopy eyelids
  • Eyelash growth
  • Eye redness
  • Itching
  • Stinging

Nitric oxides

A gas naturally produced by the body called nitric oxide supports the function of cells that help regulate the trabecular meshwork. An example of a nitric oxide medication used to treat glaucoma is latanoprostene bunod. When metabolized by the body, this medication forms two active ingredients: latanoprost acid and nitric oxide.

Nitric oxide helps lower eye pressure by increasing the amount of aqueous humor that drains from the eye through the trabecular meshwork and another route called the uveoscleral pathway. In this unconventional route, eye fluid flows across the iris and front face of the ciliary muscle (a ring of smooth muscle in the eye’s uvea or middle layer) and drains through the sclera (white of the eye).

The most common side effect of this medicine is redness in the white part of the eye or the inside of the eyelid. Eye irritation may also occur. In rare cases, painful irritation may develop in the cornea. Swelling of the eye and eyelid lining may also occur.

Rho kinase inhibitors

Also called ROCK inhibitors, these keep rho kinase enzymes from increasing fluid production in the eye. They also help relax smooth muscle within the trabecular meshwork, which helps promote the flow of aqueous humor through the drainage canals. The only ROCK inhibitor currently prescribed for glaucoma is netarsudil, which can cause side effects such as eye redness and discomfort.

Laser therapy for glaucoma

Laser surgery can help lower intraocular pressure in people with progressive forms of glaucoma or who need additional treatment to control eye pressure besides medicine. The treatment may be just as effective as medicine for treating open-angle glaucoma. In some cases, it’s the first line of treatment for people newly diagnosed with the condition.

Examples of laser therapies for glaucoma include:

Laser trabeculoplasty

This short, painless procedure uses laser beams to expand the drainage holes in the eyes. During laser trabeculoplasty, a high-intensity beam of light is aimed at a special lens placed on the eye, which causes chemical and biological changes to the tissue within the trabecular meshwork. This allows for better flow of fluids out of the eye and into the bloodstream.

The results of this glaucoma treatment can last around one to five years or longer, although medications still need to be used. Examples of commonly used laser trabeculoplasty techniques include:

Argon laser trabeculoplasty (ALT): This older procedure uses a small laser beam to expand the drainage angle and unclog channels in the trabecular meshwork. ALT can only be repeated once.

Selective laser trabeculoplasty (SLT): During SLT, pigmented cells are selectively targeted, which leaves untreated sections of the trabecular meshwork intact. This glaucoma treatment can be repeated multiple times, as the effect eventually wears off.

MicroPulse laser trabeculoplasty (MLT): This treatment uses diode laser energy, which converts electrical energy into laser light energy. MLT delivers tiny pulses of energy instead of longer, continuous wavelengths. Therefore, it’s gentler and less disruptive to the eye than standard laser treatments.

Eye tissue is allowed to cool in between laser pulses. This helps minimize the chances of damage to the trabecular network.

Laser peripheral iridotomy

Laser peripheral iridotomy (LPI) is often used to treat acute or chronic closed-angle glaucoma. LPI corrects the abnormal position of the iris to stabilize eye pressure. Over time, this helps prevent acute angle-closure attacks (in which eye pressure suddenly and rapidly increases).

This treatment uses a targeted beam of light to create a tiny hole on the outer edge of the iris. This facilitates the passage of fluid between the anterior chamber (front part of the eye) and the posterior chamber (area behind the iris), bypassing the eye’s normal drainage route at the angle where the iris and cornea converge.

Surgery for glaucoma

Surgery is often reserved for people at high risk of significant vision loss from glaucoma.

Glaucoma filtration surgery

This is the most common type of glaucoma surgery. During this procedure, a new drainage route (called a trabeculectomy or tube shunt) is created, allowing eye fluids to bypass the clogged drainage canals. This reduces pressure on the optic nerve.

This treatment may be effective for at least one year, at which point the opening may start to close. The same eye can be treated multiple times with this technique.

Partial thickness surgeries

Alternative filtration procedures (such as viscocanalostomy, deep sclerectomy, and canaloplasty) may be used to remove only part of the drainage system to improve fluid outflow.

Minimally invasive glaucoma surgery (MIGS)

Also called microincisional or microinvasive glaucoma surgery, these newer surgical procedures help lower eye pressure with minimal tissue trauma and faster recovery times. Some of these procedures involve implantation of devices (such as a tiny stent or tube) in the trabecular meshwork, enhancing fluid outflow and decreasing eye pressure. MIGS is often performed at the same time as cataract surgery, allowing for one small incision to treat both conditions.

Tube implantation

Also called aqueous shunt surgery, this procedure involves placement of a tiny tube into the front chamber of the eye (often right in front of the iris). Fluid flows through the tube into an area in the back of the eye close to the implant, where it collects and drains into the bloodstream.

Visual rehabilitation for glaucoma

If you’ve experienced vision loss due to glaucoma, your HCP may recommend visual rehabilitation. This involves working with a low-vision specialist, such as an occupational therapist or physiatrist (a medical doctor who specializes in physical and rehabilitative medicine). The goal is to help you better adjust to vision changes.

These specialists can help you develop strategies for completing daily activities such as shopping, cooking, reading, writing, and moving around safely. They teach you how to use low-vision adaptive technology and assistive devices such as:

  • Screen readers, which help convert digital text to speech
  • Large-button keyboards to make typing easier
  • Magnification software that assists with reading on computers and other devices
  • Handheld or wearable magnifiers, which can magnify what you see
  • Telescopic devices worn over glasses, which can make objects in your visual field appear larger
  • Special eyeglasses equipped with prisms, which may aid with peripheral vision and help you steer clear of obstacles you may not easily see

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What are the possible complications of glaucoma?

Complications of glaucoma include varying degrees of visual field loss, which roughly 1 in 10 people with the eye disease experience. This can eventually progress to no light perception (NLP) vision.

The most severe form of vision loss and blindness, NLP means you’re completely blind and can’t see or detect any form of light. Only about 5 percent of people with glaucoma become blind.

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When should you see a healthcare provider?

If you notice your vision changing or detect unusual symptoms such as blind spots, it’s a good idea to get your eyes examined by an HCP as soon as possible. Bear in mind that glaucoma tends to develop slowly, which means you may not experience symptoms right away.

Rapid changes to your vision along with other potential glaucoma symptoms that come on suddenly and intensely may signal a medical emergency. These include sudden and severe:

  • Eye pain
  • Eye redness
  • Blurry vision
  • Headache
  • Nausea or an upset stomach

You may also see rainbow-colored halos when looking at lights. These may be signs of an acute angle-closure (or closed angle) glaucoma attack. Call 911 or get emergency medical care right away if these occur, no matter which type of glaucoma you may have been diagnosed with.

What questions should you ask your healthcare provider?

No questions are off limits when it comes to talking with your HCP about your health. Be sure to ask any questions you might have about glaucoma, such as symptoms you may encounter, treatment options, and complications that may occur.

Below are a few questions to help you get the conversation going:

  • Which type of glaucoma do I have?
  • What is the likely cause of my glaucoma?
  • What is my eye pressure? Is it too high?
  • What symptoms are associated with my type of glaucoma?
  • What short- and long-term vision changes can occur due to my glaucoma type? Am I likely to go blind?
  • What are my treatment options? What are the risks and benefits of each treatment?
  • Can lifestyle interventions improve my glaucoma?
  • Which, if any, activities do I need to avoid because of my glaucoma?
  • Does my type of glaucoma raise my risk for other eye diseases? If so, which ones and why?
  • How will you monitor the progression of my glaucoma? How often do I need to get a checkup to reassess my condition?

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Can you prevent glaucoma?

senior couple wearing protective eyeglasses on an outdoor walk to prevent glaucoma

There’s no science-backed way to prevent glaucoma, but early diagnosis and treatment are key to preventing the optic nerve damage and vision loss it often causes. One of the most effective ways to do this and protect your eye health in general is by getting regular eye exams.

Check with your HCP to find out when to start getting tested for glaucoma and how often this needs to be done. In general, health experts recommend you get screened for glaucoma every:

  • 1 to 3 years after age 35, if you carry a higher risk for glaucoma
  • 2 to 4 years, if you’re younger than 40 years old
  • 1 to 3 years, if you’re between 40 and 54 years old
  • 1 to 2 years, if you’re between 55 and 64 years old
  • 6 to 12 months, if you’re 65 and older

Reduce eye pressure with exercise

If you have glaucoma or are at risk for it, be sure to talk with your HCP before starting or making significant changes to your exercise routine. You may also want to consult with a certified personal trainer or clinical exercise physiologist with experience developing training programs for people with health conditions such as glaucoma.

Moderate-intensity physical activity may help lower eye pressure associated with various types of glaucoma, such as primary open-angle glaucoma. It may also help increase ocular perfusion pressure, which helps improve blood flow through the eye (called ocular blood flow). (Ocular perfusion pressure is a measure of arterial blood pressure entering the eye, minus the intraocular pressure of the eye.)

Sticking with an exercise routine can help sustain these eye health benefits. You may want to try moderate activities such as walking briskly or jogging three or more times a week. Yoga may also help reduce eye pressure, although it’s best to avoid inverted poses such as headstands and controlled breathing techniques such as pranayama, as these can raise eye pressure.

Try to practice gentle, slow-moving forms of yoga. If you opt to practice inversions, get into these postures slowly. If you choose to continue with pranayama, avoid the phase of Ujjayi breathing in which you forcefully exhale while saying a prolonged “haaaaah.” Breathe out normally instead.

Use eye protection

Protect your eyes to help preserve your eye health, as eye injuries may lead to secondary types of glaucoma such as traumatic glaucoma. This includes wearing protective eyewear appropriate for the activity you’re doing, such as safety glasses and shields for home improvement projects or the proper goggles and helmets for sports.

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What is the outlook for glaucoma?

The outlook for glaucoma often depends on the stage it’s in, when it’s detected, and how early treatment is started. The prognosis tends to be better if the optic nerve hasn’t sustained any damage and you follow your glaucoma treatment plan correctly, adjusting it as needed with guidance from your HCP. The more damage to the optic nerve, the worse the prognosis tends to be.

Diagnosing and treating glaucoma as early as possible can help slow the progression of the disease and minimize visual impairment. Adhering to your treatment plan and keeping up with routine eye exams and glaucoma tests are key to preserving your eye health, especially since the disease can change or progress with little to no warning. Adjustments to your treatment plan may need to be made periodically based on changes to your symptoms and the results of follow-up eye tests.

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Living with glaucoma

Getting diagnosed with glaucoma and not knowing what may happen to your vision can be highly stressful. While living with glaucoma may involve making adjustments to your daily routine, this doesn’t mean you have to limit your life. Many people with the disease, especially those who stick to their glaucoma treatment plan, are able to live full and active lives.

You’re not alone. Reach out to people you trust for support. If needed, consider talking with a licensed mental health provider. Joining an in-person or online support group for people with glaucoma may also be helpful. Sharing your thoughts, hopes, and fears with people who have firsthand experience of what you're going through may improve your emotional health.

Safety tips for living with glaucoma

Keep these tips in mind to help you stay safe at home:

  • Keep pathways in your home free of obstacles and tripping hazards (such as area rugs).
  • Carry a flashlight when walking outdoors at night and install additional lighting in your home. Because your eyes may not adjust easily in dark settings when you have glaucoma, it helps to increase the brightness in dark or dim areas such as hallways or closets.
  • Mark steps and handrails inside and outside of your home with brightly colored tape or paint to help you navigate steps and stairs safely. Loss of peripheral vision can make it more difficult to see these areas.
  • Make it a point to consistently close cabinets in your kitchen, bathroom, and other areas of your home, which can reduce the risk of these doors hitting you and injuring your head.
  • Before you pick up an item on the floor, place your hand (palm facing away from you) about 12 inches from your face to make sure you don’t hit the edges of tables or countertops with your head or other body parts.

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Featured glaucoma articles

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