Normal-tension glaucoma is optic nerve damage that occurs while eye pressure stays in the normal range. Treatment aims to lower pressure further, usually by about 30 percent, and to monitor your nerve closely for change.
“You have glaucoma, but your pressure is normal.” Most patients find this sentence confusing. It sounds contradictory. It is not.
Normal-tension glaucoma is a recognised form of open-angle glaucoma. The nerve is more vulnerable than average, so ordinary pressure still harms it. That is not your fault, and you did not miss a warning sign. Glaucoma stays silent until late.
This page explains what the condition is, how I confirm it, and how I treat it. If you are still trying to find out whether glaucoma is possible, read Can I Have Glaucoma With Normal Eye Pressure?
Dr Shibal Bhartiya is a fellowship-trained glaucoma specialist and Mayo Clinic Research Collaborator with over 25 years of experience. Her approach focuses on identifying risk before damage is irreversible, simplifying treatment decisions, and protecting vision long-term. Emphasis on early detection, risk assessment, and continuity of care. She is rated 5 stars across 1,600+ patient reviews on Google.
Known for her structured approach to glaucoma risk assessment and progression analysis, Dr Shibal Bhartiya provides trusted second opinions for patients seeking clarity before major treatment decisions. Both, in person, and online.
What is normal-tension glaucoma?
Normal-tension glaucoma (NTG) is a type of open-angle glaucoma. The drainage angle is open. Your pressure stays within the statistically normal range, which means 21 mmHg or below. The optic nerve thins and your side vision narrows slowly.
Doctors also call it normal-pressure glaucoma or low-tension glaucoma. It is no milder than other types. It can cause permanent vision loss without treatment.
Causes and risk factors
Doctors do not fully understand the cause. These factors raise your risk:
- A family history of glaucoma
- Migraine or Raynaud’s phenomenon, where small vessels tighten easily
- Low blood pressure, especially at night
- Sleep apnoea
- East Asian ancestry, including Japanese and Korean populations
- Past disc haemorrhages
- Past major blood loss or shock
Blood flow and night-time blood pressure
Your optic nerve needs a steady blood supply. During sleep, blood pressure drops naturally. In some people with NTG, it drops too far and may reduce the nerve’s supply. Research on this link continues, and no treatment proves effective for blood flow itself.
Never stop or change your blood pressure tablets on your own. I ask your physician to review the dose and the timing. Read more on ocular blood flow and blood pressure and glaucoma.
Symptoms
Early NTG gives no symptoms. Late signs include patchy loss of side vision, trouble in dim light and bumping into objects. Regular check-ups catch it earlier than symptoms do.
What your eye tests can show
| Symptom | Cause | When to Worry |
|---|---|---|
| Thin optic disc with normal pressure on repeat visits | Classic normal-tension glaucoma | Any change on repeat OCT or visual field. This signals progression. |
| Pale disc rather than a cupped disc | The cause may not be glaucoma. Compressive, ischaemic or inflammatory conditions can mimic it. | Early loss of colour vision or sharpness, or field loss that stops at the midline. I arrange an MRI. |
| Normal clinic pressure, higher readings at night | Hidden pressure peaks | Visual field loss that outpaces the clinic readings. I measure pressure over 24 hours. |
| Thin central cornea | The device under-reads true pressure | Progression despite apparently low pressures. |
| Small bleed at the disc edge (disc haemorrhage) | Active stress on the nerve, common in NTG | Repeated haemorrhages. I tighten the target pressure. |
| Low night-time blood pressure on a 24-hour recording | Reduced nerve blood supply during sleep | Dizziness, or field loss after a change in blood pressure tablets. |
How I diagnose normal-tension glaucoma
I never diagnose it from one test. I assess:
- Your optic nerve and OCT scans
- Visual fields (perimetry), repeated over time
- Corneal thickness
- Gonioscopy, to rule out angle closure
- Pressure at different times of day, or over 24 hours
- A 24-hour blood pressure recording, in selected patients
- An MRI of the brain, when the pattern looks atypical
I also check for other causes, such as steroid use, past eye injury and inflammation.
How I treat normal-tension glaucoma
I set a personalised target pressure based on your nerve, not on a fixed number. The Collaborative Normal-Tension Glaucoma Study found that lowering pressure by 30 percent reduced progression. That is why I aim to lower pressure even when it already looks normal.
Not everyone needs treatment on day one. Some nerves stay stable for years. When your nerve looks stable, I may first record several visual fields over the first two years. This measures your rate of change before I commit you to lifelong drops.
Eye drops
Drops are usually the first step. I choose them with your whole health in mind, because some drops can lower night-time blood pressure or heart rate. Read about glaucoma eye drops.
Laser treatment
Selective laser trabeculoplasty (SLT) can lower pressure. The amount varies from person to person. Laser helps when drops cause side effects or are hard to use. See laser or eye drops.
Surgery
When your nerve keeps progressing despite drops and laser, I discuss surgery. Because NTG needs a low target pressure, surgery sometimes becomes necessary. Options include trabeculectomy and drainage implants. See glaucoma surgery in Gurgaon.
Whole-body factors
I ask your physician to review night-time blood pressure, sleep apnoea and migraine. Treating these may protect your nerve alongside your eye treatment.
Lifestyle, honestly
- Exercise. Regular moderate exercise helps your circulation and may lower pressure slightly. Avoid heavy straining and long head-down yoga positions.
- Diet. No diet treats glaucoma. A balanced diet with vegetables, fruit and fish supports general health.
- Smoking. Smoking harms blood vessels. Stopping helps your overall vascular health. See smoking and glaucoma.
- Sleep. If you snore or stop breathing at night, ask for a sleep study.
- Stress. Chronic stress affects wellbeing. Choose relaxation methods you will keep up.
Living with a long-term condition feels heavy at times. Read about coping strategies. Caregivers can attend visits and learn the facts through glaucoma myths.
Monitoring and follow-up
Follow-up shows whether your treatment works. In the first two years I usually record several visual fields to measure your rate of change. I repeat OCT scans and review your target pressure at each visit. Your schedule depends on your stage, your stability and your risk of progression.
Why I look at pressure over 24 hours
A clinic reading captures one moment, usually in daytime. Goldmann tonometry cannot measure your pressure at night without waking you. I have reviewed the evidence on 24-hour pressure monitoring.¹ Large swings in pressure may raise the risk of progression, beyond the average level.¹˒⁴ Many glaucoma decisions still rest on one or two readings.² I order 24-hour monitoring in selected patients, such as those who progress while clinic pressures sit in target.¹
Setting your target pressure
In my review with Clement and Shaarawy, we found the evidence for lowering pressure strong.⁵ We also found that no method of setting a target has been validated.⁵ So I treat your target as a working estimate. I recheck it against your visual fields and OCT.
What doctors often miss
- Calling every pale or thin disc glaucoma. A pale disc can point to a neurological cause.
- Skipping an MRI when the pattern is atypical. Early colour loss or midline-respecting field loss needs a closer look.
- Treating the clinic pressure only. Night-time pressure and night-time blood pressure also matter.
- Judging progression from one visual field. Fields vary. Trends count more than single tests.
- Overlooking blood pressure tablets. Dose and timing can affect the optic nerve at night.
When to see a doctor
See a Doctor Urgently
Seek same-day care for any of these:
- Sudden loss of vision in one or both eyes
- A new dark curtain or shadow across your vision
- Severe eye pain with redness, nausea or halos around lights
- New double vision, or a sudden severe headache with vision change
See a Doctor
Book an appointment soon if:
- You notice new missing patches in your side vision
- Your night vision worsens
- You missed your planned follow-up
- You feel dizzy or faint after changing blood pressure tablets (call your physician the same day if you faint)
- You want a clear review of your target pressure and treatment plan
What this means for you
Normal-tension glaucoma is serious, but you can manage it. The goal is a stable nerve over decades, not a perfect number. Your target pressure, your follow-up and your whole-body health work together.
If you still feel unsure about your diagnosis or your treatment plan, a structured second opinion can bring clarity. I review your records over time and tell you whether to observe, refine or escalate.
📞 +91 88826 38735 | 🌐 Contact Us | Second Opinion Form for teleconsults
Frequently Asked Questions
Is normal-tension glaucoma less serious than other glaucoma?
No. It can cause permanent vision loss if left untreated. Early diagnosis and regular monitoring matter as much as in any other glaucoma. Some patients stay stable for years, while others progress.
Why do I need drops if my eye pressure is already normal?
The goal is a pressure that is safe for your optic nerve, not a normal-looking number. Lowering pressure by about 30 percent reduced progression in the Collaborative Normal-Tension Glaucoma Study. Even a modest reduction may slow damage in many patients.
Can normal-tension glaucoma become severe?
Yes. Some people stay stable for many years. Others develop steady optic nerve damage. Regular visual fields and OCT scans detect progression early, so we can step up treatment in time.
How often should I be reviewed?
There is no single schedule. It depends on your stage, your stability, your pressure and your OCT and field results. In the first two years I usually record several visual fields to measure your rate of change.
Does blood pressure medicine affect normal-tension glaucoma?
It can. Blood pressure that drops too low at night may reduce blood supply to your optic nerve. Never change your tablets on your own. Ask your physician to review the dose and timing, and tell them about your glaucoma.
Book a Consultation
If you want a clear plan for your optic nerve, I am happy to review your reports. I also work with your local eye doctor when you live elsewhere.
Book an Appointment:
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This page is a part of the Glaucoma Hub. you may want to read about Glaucoma Progression, and Risk Stratification in Glaucoma. Other articles of interest could be Advanced Glaucoma Care in Gurgaon, What Good Glaucoma Care Actually Optimises For, What Happens If Glaucoma Is Left Untreated?, More Glaucoma Eye Drops is Not Better Glaucoma Care, 5 Mistakes Patients Make in Glaucoma Care and Do You Really Need Treatment for Glaucoma?
About the Author
This article was written by Dr Shibal Bhartiya, fellowship-trained glaucoma specialist and Mayo Clinic Research Collaborator, Clinical Director at Marengo Asia Hospitals, Gurugram, known for ethical, patient-centred glaucoma care and independent glaucoma second opinions. She is also the Program Director for Community Outreach & Wellness; and for the Marengo Asia International Institute of Neuro and Spine.
She has published peer-reviewed research on glaucoma management, examining how treatment decisions should balance medical evidence, patient preferences, and long-term vision outcomes.
As Editor-in-Chief of Clinical and Experimental Vision and Eye Research and Executive Editor of the Journal of Current Glaucoma Practice (Pubmed Indexed, official journal of the International Society of Glaucoma Surgery), Dr Shibal Bhartiya brings editorial and research depth to every clinical decision. Her 200+ publications, including 90+ PubMed-indexed publications and 28 edited textbooks span glaucoma biology, surgical outcomes, health equity, and emerging diagnostics.
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If you are unable to come to Dr Bhartiya’s clinic: Read more about teleconsultation
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Key Published Research by Dr Shibal Bhartiya on Eye Pressure
- Bhartiya S, Gangwani M, Kalra RB, Aggarwal A, Gagrani M, Sirish KN. 24-hour intraocular pressure monitoring: the way ahead. Rom J Ophthalmol. 2019;63(4):315-320. PMID 31915728.
- Bhartiya S, Wadhwani M, Rai O, Patuel M, Dorairaj S, Sirish KN. Diurnal variation of IOP in angle closure disease: are we doing enough? Rom J Ophthalmol. 2019;63(3):208-216. PMID 31687621.
- Bhartiya S, Ichhpujani P. Diurnal intraocular pressure fluctuation in eyes with angle-closure. J Curr Glaucoma Pract. 2015;9(1):20-23. PMID 26997828.
- Bhartiya S, Ichhpujani P. The need to maintain intraocular pressure over 24 hours. J Curr Glaucoma Pract. 2012;6(3):120-123. PMID 26997767.
- Clement CI, Bhartiya S, Shaarawy T. New perspectives on target intraocular pressure. Surv Ophthalmol. 2014;59(6):615-626. doi:10.1016/j.survophthal.2014.04.001. PMID 25081325.