Types of Glaucoma: What Patients Need to Know
Primary Open-Angle Glaucoma
Primary open-angle glaucoma is the most common form of the disease, and it is often called the silent thief of sight because it causes no pain and no noticeable symptoms in its early stages. Regular comprehensive eye exams are the most reliable way to detect it before significant damage occurs. Left unmanaged, it can lead to irreversible vision loss over time.
This type occurs when the eye's natural drainage system, called the trabecular meshwork, becomes partially blocked over time. Fluid that normally circulates through the eye cannot drain efficiently, causing pressure inside the eye to rise gradually. The drainage angle itself appears open and normal on examination, but microscopic changes prevent proper fluid flow. Both eyes can be affected, though each eye may progress at a different rate.
Several factors raise a person's chances of developing this condition. Knowing your risk can help you and your eye doctor decide how often you should be screened.
- Age over 40, with risk increasing with each decade
- Family history of glaucoma in a parent or sibling
- African American, Hispanic, or Asian ancestry
- High eye pressure, also known as ocular hypertension
- Thin corneas or a large cup-to-disc ratio in the optic nerve
- Diabetes, high blood pressure, or heart disease
- Severe nearsightedness, also called myopia
In the early stages, most people notice nothing at all. As the disease progresses, gradual loss of side (peripheral) vision is usually the first change. Difficulty seeing in dim light and reduced depth perception can follow. Because symptoms tend to appear late, much of the damage can occur silently before a patient realizes anything is wrong.
Accurate diagnosis requires a combination of tests, not just an eye pressure reading. At our practice, we use advanced diagnostic tools to get a complete picture of your optic nerve health.
- Eye pressure measurement using tonometry
- Dilated optic nerve examination
- Visual Field Testing to map peripheral vision
- Optical Coherence Tomography (OCT) to measure nerve fiber thickness with precision
- Gonioscopy to examine the drainage angle directly
- Corneal thickness measurement, called pachymetry
The primary goal of treatment is to lower eye pressure enough to prevent further optic nerve damage. The right approach depends on how far the disease has progressed and how your eye responds to each option.
- Prescription eye drops such as prostaglandin analogs, beta-blockers, or alpha agonists to reduce pressure
- Selective Laser Trabeculoplasty (SLT), a laser procedure that improves the drainage angle
- Minimally Invasive Glaucoma Surgery (MIGS) options including the iStent, Hydrus Microstent, and Kahook Dual Blade for mild to moderate disease
- Sustained-release drug delivery implants such as Durysta and iDose for patients who need long-term pressure control
- Trabeculectomy or tube shunts for advanced or medication-refractory glaucoma
Our surgical team, including Dr. Salman Dar, brings specialized glaucoma surgery expertise and laser training to help determine which approach is best suited to your individual case.
Most people with well-controlled open-angle glaucoma maintain good functional vision and continue normal daily activities. Consistent use of prescribed drops, keeping all follow-up appointments, and promptly reporting any vision changes are the most important steps you can take to protect your sight.
Angle-Closure Glaucoma
Angle-closure glaucoma happens when the iris, the colored part of the eye, shifts forward and blocks the eye's drainage angle entirely, preventing fluid from leaving the eye. This blockage can build up slowly over months or years, or it can happen suddenly in what is called an acute attack, which is a medical emergency. Knowing the warning signs and your personal risk can be sight-saving.
Unlike open-angle glaucoma, where the drainage angle looks normal but is functionally impaired, angle-closure glaucoma involves a physical obstruction of the drainage angle by the iris. When fluid is completely blocked, pressure inside the eye can spike to dangerous levels very quickly. The acute form requires immediate emergency care, while the chronic form develops slowly and may be nearly symptom-free for a long time.
Certain anatomical features and demographic factors are closely associated with this type of glaucoma. Your eye doctor can examine your drainage angle to assess your personal risk level.
- People of Asian, Inuit, or Hispanic descent
- Women, who are affected more often than men
- Adults over 55
- Farsighted individuals (hyperopia) with smaller, more crowded eye anatomy
- Family history of angle-closure glaucoma
- Cataracts that cause the lens to swell and push the iris forward
- Certain medications that dilate the pupil, including some antidepressants and decongestants
An acute angle-closure attack requires emergency medical care without delay. Permanent vision loss can occur within hours if pressure is not relieved. Seek care immediately if you or someone you know experiences any of the following.
- Intense eye pain accompanied by a severe headache
- Sudden blurred or dramatically decreased vision
- Colored halos or rainbow rings around lights
- Eye redness and excessive tearing
- Nausea or vomiting alongside eye symptoms
- An eye that feels unusually firm or hard to the touch
Chronic angle-closure glaucoma develops gradually and may cause only mild, intermittent symptoms, such as brief episodes of blurred vision or halos around lights in dim conditions. Because these signs are subtle, this form is often missed without a thorough eye exam that includes gonioscopy to inspect the drainage angle directly.
An acute attack is treated first with medications to rapidly lower eye pressure, followed by Laser Peripheral Iridotomy (LPI), a procedure that creates a small opening in the iris to restore fluid flow. In many cases, we also treat the unaffected eye preventively, since this condition commonly affects both eyes. If laser treatment is not sufficient, surgical options such as trabeculectomy or lens extraction may be recommended. For patients identified as at risk before any attack occurs, preventive LPI is an effective option.
Normal-Tension Glaucoma
Normal-tension glaucoma is a form that surprises many patients because eye pressure readings fall within the normal range, yet optic nerve damage and vision loss still occur. It accounts for a meaningful portion of open-angle glaucoma cases and is particularly common in certain populations. Comprehensive optic nerve evaluation, rather than pressure testing alone, is essential to identify this type.
In this form, the optic nerve sustains progressive damage despite eye pressure that stays below the traditionally accepted upper limit of normal (below 21 mmHg). Researchers believe that factors beyond pressure, including reduced blood flow to the optic nerve and increased nerve sensitivity, play important roles. Because pressure readings appear reassuring, this type can be missed when exams are limited to pressure checks only.
Certain health factors and backgrounds are associated with a higher likelihood of developing normal-tension glaucoma.
- Japanese ancestry, where this type is disproportionately common
- Women, particularly after menopause
- Family history of normal-tension or low-pressure glaucoma
- Low blood pressure, especially during sleep
- Vasospastic disorders such as migraines or Raynaud's phenomenon, which affect blood vessel tone
- Sleep apnea or other conditions that reduce blood oxygen levels
Because eye pressure does not flag this type, diagnosis depends heavily on careful optic nerve imaging and visual field analysis. Optical Coherence Tomography (OCT) allows us to measure the thickness of nerve fiber layers with high precision, and Visual Field Testing maps any peripheral vision changes that have already occurred. Repeat testing over time is often needed to confirm a pattern of progression.
The treatment strategy centers on lowering eye pressure even further below normal to reduce stress on the optic nerve, and on supporting healthy blood flow to the nerve itself. Treatment options may include prescription eye drops to lower pressure, lifestyle measures such as regular moderate exercise to support circulation, blood pressure management to avoid nighttime pressure drops, and treatment of contributing conditions like sleep apnea. SLT and MIGS procedures may also be considered when appropriate.
Secondary and Congenital Glaucoma
Some forms of glaucoma develop because of an identifiable underlying cause, whether that is another eye condition, a medication, an injury, or a problem present from birth. These types require a treatment approach that addresses both the source of the problem and the elevated eye pressure. Understanding the underlying trigger is critical to choosing the right care.
Secondary glaucoma occurs when a known factor disrupts the eye's normal fluid drainage, causing pressure to rise and the optic nerve to sustain damage. Common underlying causes include inflammation from a condition called uveitis, prolonged use of steroid medications, protein deposits in the eye (pseudoexfoliation), pigment granules shed from the iris (pigmentary glaucoma), abnormal blood vessel growth related to diabetes (neovascular glaucoma), and trauma to the eye. Cataract-related complications can also trigger secondary glaucoma in some cases.
Symptoms vary widely depending on the cause. Some patients experience eye pain, redness, light sensitivity, or sudden vision changes, while others develop gradual vision loss similar to primary glaucoma. Treatment must address the root cause alongside the pressure issue, which may involve anti-inflammatory medications, management of systemic conditions like diabetes, adjusting steroid use when possible, and standard glaucoma medications, laser procedures, or surgery as needed.
Congenital glaucoma is a rare condition present from birth, occurring when the eye's drainage system does not develop properly. Fluid builds up inside the eye, increasing pressure and potentially damaging the developing optic nerve. Early recognition and treatment are essential, since delays can result in permanent vision loss during a critical window of visual development.
Parents and caregivers should watch for these warning signs and report them to a pediatric eye doctor promptly.
- Eyes that appear unusually large or noticeably different in size
- Cloudy or hazy corneas
- Excessive tearing without crying
- Sensitivity to light, causing squinting or covering the eyes
- Frequent eye rubbing or keeping eyes closed
Surgery is typically the first-line treatment, since medications are less effective in young children. Procedures such as goniotomy or trabeculotomy are used to open or create drainage pathways. Children treated early often develop good vision, but they require lifelong monitoring and may need additional care as they grow.
Our Glaucoma Care Team and Technology
Managing glaucoma well requires more than a single tool or technique. It requires experienced clinicians, advanced technology, and a plan tailored to how your specific type of glaucoma behaves. Our team at Dulles Eye Associates is committed to offering the full range of modern glaucoma care under one roof.
Dr. Salman Dar focuses on glaucoma surgery with extensive expertise in both laser-based and minimally invasive surgical approaches. Dr. Remil Simon brings dedicated experience in minimally invasive glaucoma surgery, helping patients with mild to moderate disease avoid or delay more involved procedures. Together, they provide care for the full spectrum of glaucoma, including medication-refractory cases where standard treatments have not provided adequate control.
Accurate diagnosis and monitoring depend on tools that can detect subtle changes before they become significant. We use Optical Coherence Tomography (OCT) to generate detailed images of optic nerve fiber layers, and Visual Field Testing to precisely map peripheral vision. These tools allow us to track your disease over time and adjust your treatment plan based on objective data rather than symptoms alone.
When drops or laser treatment are not enough, our surgeons offer a wide range of surgical solutions. Minimally invasive options include the iStent, Hydrus Microstent, and Kahook Dual Blade, all of which can lower pressure with a shorter recovery than traditional surgery. For more advanced disease, trabeculectomy and tube shunts remain highly effective options. Sustained-release implants including Durysta and iDose are also available for patients who benefit from long-acting pressure control without daily drops. Selective Laser Trabeculoplasty (SLT) and Laser Peripheral Iridotomy (LPI) are performed in-office for appropriate patients.
Many patients with glaucoma also develop cataracts as they age. When both conditions are present, combining cataract removal with a MIGS procedure in a single operation can address both problems at once, reducing eye pressure while simultaneously restoring clarity of vision. Our surgical team is experienced in these combined procedures and can help determine whether you are a good candidate.
Frequently Asked Questions
These questions address practical decisions and situations that often come up as patients learn to manage their glaucoma long-term.
Yes, absolutely. Controlled pressure is an important goal, but it does not tell the whole story. Optic nerve damage and visual field changes can still occur even when pressure readings look acceptable. Routine visits allow your eye doctor to track these changes with OCT imaging and visual field tests, and to adjust your treatment plan before meaningful vision loss occurs. Attending every scheduled appointment is one of the most important things you can do for your long-term outcome.
Laser procedures such as SLT or LPI are typically performed in an office or procedure room, require no incisions, and involve minimal recovery time. They work by improving fluid drainage through existing pathways. Surgical options, including MIGS procedures like the iStent or Hydrus Microstent, and more traditional surgeries like trabeculectomy, involve creating or augmenting drainage pathways within the eye. Surgery is generally recommended when drops and laser treatments have not achieved sufficient pressure control, or when the disease is more advanced at the time of diagnosis.
For some patients, sustained-release implants such as Durysta or iDose offer an alternative to daily drops. These devices deliver medication continuously over an extended period, which can be particularly helpful for patients who have difficulty with adherence or who experience side effects from topical drops. Whether this is appropriate for you depends on your specific type of glaucoma, your pressure targets, and your overall eye health. Your eye doctor can review whether you are a candidate.
Medication-refractory glaucoma refers to cases where eye pressure cannot be adequately controlled despite trying multiple medications, laser treatments, or earlier surgeries. This does not mean the condition is untreatable. In these situations, more advanced surgical options such as trabeculectomy or tube shunts become important tools. Our team has experience managing complex, refractory cases and can discuss what the most appropriate next step looks like for your situation.
These symptoms can signal an acute angle-closure glaucoma attack or another serious eye emergency, and they require immediate attention, not a scheduled appointment. Go to an emergency room or contact an eye care provider right away. Time is critical in preserving vision during an acute episode, and waiting even a few hours can result in irreversible damage. If you have already been identified as at risk for angle-closure glaucoma, ask your eye doctor about preventive laser treatment before any emergency occurs.
The type of glaucoma you have is determined through a thorough examination that includes pressure testing, gonioscopy to inspect the drainage angle, optic nerve imaging, and visual field analysis. The type does significantly influence treatment. For example, angle-closure glaucoma typically requires LPI as a primary intervention, while normal-tension glaucoma may require lowering pressure well below normal ranges and addressing blood flow factors. Secondary glaucoma requires treating the underlying cause alongside the pressure. Your eye doctor will tailor the plan to your specific diagnosis.
Protecting Your Vision Starts Here
Glaucoma is a lifelong condition, but with the right care team and a plan built around your specific type and stage of disease, most patients can protect their vision and maintain their quality of life for years to come. At Dulles Eye Associates, our fellowship-trained eye doctors bring advanced surgical skills, precise diagnostic technology, and genuine commitment to patient-centered care to every visit. We welcome patients throughout Northern Virginia and the broader Washington, DC metro area, and we are here to help you take the next step in protecting your sight.
Out standing customer service, every time I walk in I get a warm welcome with great smiles. Always have a great experience with Mehvish in the front desk and Zeba at the optical. Highly recommend it:)
Asif Gill
I just had my LASIK surgery with Dr. Nasrullah, and everything went smoothly exactly as explained. Repeating post-op instructions helped a lot. 24 hours later, I could drive and see clearly.
Farah C
I classify as very elderly. I have been a patient at Dulles eye for approximately 8 years I have been completely satisfied, especially with Dr Dar. I recommend the entire practice with no reservation.
Dennis Monk
Wonderful practice - compassionate, kind and professional. Thanks Dr. Kang for everything.
Connie Walker
From check-in to check-out, the staff was professional and kind. Dr. Najafi listened carefully, answered all my questions with patience, and made me feel comfortable. I’ll be back for my next exam!
June Williams