Dr. Callahan is a competent professional who answered all my questions with patience. Her caring staff provided reminders and follow-ups. I had cataract surgery on both eyes; now 20/20 vision!
John Mcallorum
Normal-Tension Glaucoma: What It Is and How We Treat It
Recognizing Symptoms and Risk Factors
Normal-tension glaucoma earns its reputation as a silent condition because it rarely causes symptoms in the early stages. Knowing the warning signs and risk factors helps you stay ahead of damage that would otherwise go unnoticed.
In the beginning, normal-tension glaucoma causes no pain, redness, or noticeable vision changes. The damage starts at the edges of your visual field, and the brain tends to fill in those gaps automatically so you may not notice anything is missing. By the time symptoms become obvious, meaningful damage has often already occurred.
Routine comprehensive eye exams are the only reliable way to detect this condition before you experience any symptoms.
As the condition progresses, blind spots begin to form in your side (peripheral) vision. These patches grow slowly and can eventually affect central vision if the condition is left untreated.
- Difficulty noticing objects to the side while looking straight ahead
- Trouble navigating in busy spaces or while driving
- Bumping into objects on either side
- Missing curbs or steps due to gaps in peripheral vision
Several general health conditions are associated with a higher risk of normal-tension glaucoma. These include cardiovascular disease, migraines, and any condition that affects blood flow to the eyes. Low blood pressure, particularly during nighttime sleep, can reduce circulation to the optic nerve and contribute to damage. Sleep apnea has also been linked to elevated risk.
If a parent, sibling, or child has been diagnosed with glaucoma of any type, your risk is meaningfully higher. Genetic factors appear to influence both optic nerve sensitivity and the structure of the eye's drainage system. We recommend regular screening for relatives of glaucoma patients, even when they have no symptoms.
Risk increases sharply after age 60, and women are diagnosed more frequently than men, though the reasons for the gender difference are still being studied. Japanese populations have the highest known rates of normal-tension glaucoma, and Asian ancestry in general carries somewhat elevated risk. People of any background can develop this condition.
How We Diagnose Normal-Tension Glaucoma
Diagnosing normal-tension glaucoma involves several tests that together paint a complete picture of your optic nerve health, eye pressure patterns, and vision. No single test is enough on its own.
We measure eye pressure using a tonometer, a device that gently touches the surface of the eye after numbing drops are applied. Because pressure naturally fluctuates throughout the day, we may check it at different times or schedule multiple visits to establish a reliable pattern. Normal-tension glaucoma is confirmed when pressure consistently stays below 21 mmHg but optic nerve damage is still present.
The thickness of your cornea, the clear front surface of the eye, can affect how accurately pressure measurements reflect the true pressure inside the eye. Thinner corneas may cause pressure to read lower than it actually is, while thicker corneas can cause it to read higher. We measure corneal thickness using a quick, painless test called pachymetry and use that information to interpret your pressure readings more accurately.
- Central corneal thickness measured by pachymetry
- Time of day when pressure is measured, since it fluctuates naturally
- Prior corneal surgery or irregularities that can affect readings
- Factors during the test such as breath-holding or eyelid squeezing
Our eye doctors examine the optic nerve at the back of the eye using specialized instruments and imaging technology. We take detailed photographs and scans at your initial visit to establish a baseline, then compare them at future visits to detect any changes. Optical coherence tomography (OCT) measures the thickness of the nerve fiber layer and can identify early thinning before vision loss becomes noticeable.
- OCT imaging to measure optic nerve fiber thickness
- Fundus photography to document the shape and color of the optic disc
- Nerve fiber layer analysis to detect subtle thinning
- Comparison images at follow-up visits to track changes over time
A visual field test maps where your vision is strong and where blind spots may be forming. During the test, you look into a machine and press a button each time you see a small light appear in different locations. The test takes about 10 to 15 minutes per eye and requires focused attention. We repeat it regularly to determine whether any areas of vision loss are stable or progressing.
We perform a procedure called gonioscopy to examine the drainage angle, the area inside the eye where fluid exits. A special lens is placed on the eye after numbing drops are applied, allowing a clear view of this drainage structure. This test helps confirm the angle is open and not blocked, which rules out other types of glaucoma and helps guide our treatment approach.
Ruling Out Other Causes of Optic Nerve Damage
When findings do not fit a typical pattern, we look carefully for other conditions that can damage the optic nerve. Getting the diagnosis right is essential to making sure you receive the most appropriate care.
Certain findings during your exam may lead us to investigate beyond the standard glaucoma workup. These situations are not common, but they are important to identify promptly so nothing is missed.
- Significant asymmetry between the two eyes in nerve damage or vision loss
- Visual field patterns that do not match typical glaucoma presentations
- Rapid decline in vision or nerve appearance over a short period
- Decreased color vision or unusual pupil responses
- Unusual optic disc pallor that seems out of proportion to the degree of damage
- Very young age at presentation or accompanying neurologic symptoms
Additional steps may include repeat visual fields and OCT testing, a review of all current medications including steroids, and occasionally neuroimaging based on our clinical judgment.
Because circulation problems may contribute to normal-tension glaucoma, we sometimes recommend evaluations beyond the eye exam. Checking blood pressure, including patterns during nighttime sleep, can uncover circulation issues that deserve attention. We may refer you to your primary care doctor or a cardiologist to address heart health, blood pressure patterns, or sleep disorders.
It is important not to change or stop any blood pressure medications without consulting the doctor who prescribed them. Managing these factors requires careful balance between supporting optic nerve circulation and maintaining control of heart and stroke risk.
Treatment Options We Offer at NewView Eye Center
Even when eye pressure is already within the normal range, reducing it further has been shown to slow or stop optic nerve damage in normal-tension glaucoma. Our treatment approach is tailored to each patient and may involve a combination of eye drops, laser procedures, and coordination with other specialists.
Eye drops are often the first line of treatment. They work by either reducing the amount of fluid the eye produces or improving how well fluid drains out. Our eye doctors select the right type based on your overall health, other medications you take, and how your eye responds.
- Prostaglandin analogs to increase fluid outflow from the eye
- Beta-blockers to reduce fluid production (used with caution in asthma or certain heart conditions)
- Alpha agonists that act on both production and drainage
- Carbonic anhydrase inhibitors for additional pressure reduction
- Rho-kinase inhibitors as an option for some patients
Each class of eye drop carries potential side effects. Prostaglandins may cause changes to eyelash growth or skin tone around the eyes. Alpha agonists can cause allergic reactions in some patients. Preservatives in certain drops can worsen dry eye over time. Our team reviews your regimen regularly and adjusts it as needed.
The goal is typically to lower your eye pressure by at least 30 percent from your starting level. For patients whose nerve damage is progressing more quickly, we may aim for a greater reduction. Targets are individualized based on the severity of existing damage, the rate of progression, corneal thickness, and how your body responds to treatment.
We monitor your response closely and revise your target pressure if circumstances change. No two patients are alike, and we adjust the plan accordingly over time.
Selective laser trabeculoplasty, or SLT, is an in-office laser procedure that uses gentle, targeted energy to stimulate the eye's natural drainage system and improve fluid outflow. It can lower eye pressure meaningfully and may reduce the number of eye drops you need, though many patients still continue with some medication. The effect of SLT can diminish over time, but the procedure can often be repeated.
- Performed in our office with no incisions and minimal discomfort
- Most patients return to normal activities the same day
- Temporary light sensitivity or mild blurring may occur for a few hours after
- A follow-up visit is scheduled within a few weeks to check pressure
- There is a small risk of a temporary pressure spike immediately after treatment
Contact our office right away if you experience severe pain, significant vision changes, or worsening redness after an SLT procedure.
YAG laser peripheral iridotomy (YAG PI) creates a small opening in the iris, the colored part of the eye, to improve fluid flow and relieve certain types of pressure buildup. While it is used more commonly in angle-closure glaucoma, our eye doctors evaluate each patient's anatomy to determine which laser approach is most appropriate. We offer a full range of in-office laser treatments as part of our glaucoma care.
Minimally invasive glaucoma surgery, or MIGS, includes a group of procedures designed to improve fluid drainage with a smaller incision and faster recovery than traditional surgery. We offer goniotomy as part of our MIGS options. MIGS procedures are well suited for patients who need more pressure reduction than drops and laser alone can provide, but who are not yet candidates for more involved surgery.
The amount of pressure reduction from MIGS is typically more modest than from traditional surgery. Our eye doctors will discuss which approach fits your situation based on your current pressure, the degree of nerve damage, and your overall health.
If medications, laser treatments, and MIGS are not sufficient to halt progression, more involved surgical options may be considered. For patients who need very low target pressure, procedures such as trabeculectomy (which creates a new drainage pathway) or tube shunt surgery may offer more significant pressure reduction. Our team will refer you to the appropriate surgical specialist when more complex intervention is indicated and will coordinate that care closely.
When circulation problems appear to be contributing to optic nerve damage, we work with your other physicians to address them. This may involve coordinating with your primary care doctor to review blood pressure medication timing, treating sleep apnea, or managing underlying cardiovascular conditions. Improving circulation to the optic nerve is a meaningful part of a complete treatment plan for many patients with normal-tension glaucoma.
Managing Normal-Tension Glaucoma Over Time
Glaucoma is a lifelong condition that requires consistent monitoring and ongoing care. Staying engaged with your treatment plan is the most important thing you can do to protect your remaining vision.
After diagnosis, we typically schedule follow-up visits every three to six months to check your optic nerve and visual field. If your condition is stable over time, we may extend visits to once or twice a year. Each appointment includes pressure measurement, optic nerve evaluation, and periodic visual field testing to catch any changes early.
Vision that has already been lost from glaucoma cannot be recovered. Our goal is to prevent further damage, which is why consistent monitoring matters so much.
While lifestyle changes alone cannot replace medical treatment, healthy daily habits can support your overall circulation and general eye health. These steps complement the care your eye doctor provides.
- Use your prescribed eye drops at the same times each day as directed
- Wait at least five minutes between different eye drops if using more than one
- Maintain a regular sleep schedule and seek treatment for sleep disorders
- Stay physically active and eat a diet rich in leafy greens and omega-3 fatty acids
- Avoid smoking, which negatively affects circulation throughout the body
- Continue all prescribed cardiovascular medications and consult your prescribing doctor before making any changes
Normal-tension glaucoma usually progresses slowly, but sudden changes always need prompt attention. Contact our office for a same-day evaluation if you notice any rapid increase in vision loss or new blind spots.
Some symptoms require emergency department evaluation and should not wait for an office appointment.
- Sudden severe vision loss or a dark shadow across any part of your vision
- Severe eye pain accompanied by nausea or vomiting
- New flashes of light together with many floaters and vision loss
- One-sided weakness, difficulty speaking, or a severe headache with eye pain
- Sudden halos around lights with redness and pain
Managing normal-tension glaucoma often involves your eye doctor, primary care physician, and other specialists working together. We share relevant information about your treatment and test results to ensure everyone is aligned. Keeping all your doctors informed about any changes in your medications or health helps prevent conflicts between treatments and supports your overall well-being.
Frequently Asked Questions
These questions address the practical decisions and concerns that often come up after a diagnosis of normal-tension glaucoma.
Without treatment, this condition can progress to severe vision loss, including legal blindness. With early detection, consistent treatment, and regular monitoring, it is often possible to slow progression substantially and preserve functional vision for many years. Outcomes depend heavily on how much damage has already occurred at the time of diagnosis and how closely the treatment plan is followed.
Yes. Even though your pressure falls within the normal range, reducing it further, typically by at least 30 percent, has been shown to slow or stop optic nerve damage. The principle is that your particular optic nerve appears to be sensitive to its current pressure level, and bringing it lower reduces the stress on those nerve fibers. This is why treatment is still recommended even when your numbers look acceptable on paper.
Genetic factors do contribute to normal-tension glaucoma, but many patients have no family history at all, which means other factors like circulation and optic nerve structure also play significant roles. If you have been diagnosed, we do recommend that your immediate family members schedule a comprehensive eye exam that specifically includes optic nerve evaluation. Early detection in relatives can prevent significant vision loss.
The core tools, including eye drops, SLT laser, and surgery, are similar to those used in other forms of open-angle glaucoma. The key difference is that target pressure goals are typically set lower, because we are starting from a normal baseline and need to reduce it further to achieve a meaningful protective effect. We also pay closer attention to blood flow and cardiovascular factors, since those appear to play a larger role in this form of the disease.
If you miss a dose, use your drops at the next scheduled time rather than doubling up. Missing an occasional dose is less harmful than the pressure spike that can result from applying too many drops too close together. Consistency over time matters far more than a single missed application. If you find it difficult to remember your drops regularly, let our team know so we can help you find a workable routine.
After SLT, many patients experience temporary light sensitivity or mild blurring for a few hours. We recommend arranging a ride home for your own comfort and safety, though you may feel fine relatively quickly. Before your procedure, ask our team specifically about what to expect given your individual circumstances so you can plan accordingly. Most patients return to normal activities, including driving, by the following day.
See Our Eye Doctors at NewView Eye Center
If you have been diagnosed with normal-tension glaucoma or have risk factors that concern you, our experienced team at NewView Eye Center is here to help. We offer comprehensive glaucoma evaluation and a full range of in-office treatments, including SLT laser therapy, YAG laser procedures, and MIGS, all delivered with the personalized attention our patients across Northern Virginia have trusted for decades. We look forward to partnering with you to preserve your vision for the long term.
What our Patients Says
Explore More
Find more information about our doctors, services, and technology that keep your eyes healthy and your vision at its best.