Glaucoma and Stress: What the Research Actually Says, explains Dr Shibal Bhartiya. Most people know glaucoma damages vision. Fewer know…
Tag: normal tension glaucoma diagnosis
Can Routine Eye Tests Miss Glaucoma?
It is difficult to believe that sometimes routine eye tests miss glaucoma. Most patients diagnosed with glaucoma say the same thing:
“But I was getting regular eye check-ups.”
This question is painful, but very important.
Routine eye tests can sometimes miss early glaucoma. Not because doctors are careless, and not because patients did anything wrong, but because glaucoma is a quiet disease that often hides in plain sight.
Understanding this helps patients make calmer, better decisions.
Why Routine Eye Tests Miss Glaucoma
1. Glaucoma Has No Early Symptoms
In early glaucoma, vision is usually perfect. You can read clearly, drive, and work normally while small optic-nerve fibres are already lost. This is called structural damage before functional loss.
Routine exams focused on glasses or cataract may not detect this.
2. Eye Pressure Can Be Normal
Many patients have normal-tension glaucoma. So a quick pressure check does not rule out disease. Moreover, your eye pressure fluctuates through the day. This is called diurnal variation of IOP.
Eye pressure is only one part of glaucoma evaluation, and moreover, one single reading is not adequate representation of what happens through the day. This is one of the reasons why routine eye tests miss glaucoma.
3. Single Tests Can Mislead
Glaucoma diagnosis needs a combination of:
• optic nerve examination
• OCT imaging
• visual field testing
• corneal thickness
• angle examination (gonioscopy / ASOCT)
• family history
• comparison over time
Looking at one test alone can miss subtle disease, or cause unnecessary fear.
If your OCT shows red areas or your field test is flagged, do not panic. Many of these findings need careful interpretation before they mean anything definitive.
4. The Brain Compensates
Patients adapt quietly. They stop night driving. Read more slowly. Walk carefully in dim light. the vision charts and power of glasses remain normal.
Routine exams rarely ask about these subtle changes.
5. Follow-Up Drift
Documentation of clinical findings is often inadequate. Patients are told to return after one year. Some don’t. Others just get their power of glasses checked. Some change doctors, others lose records. Sometimes reports are not compared carefully. Small progression is thus missed.
This is a systems problem, not a patient mistake.
How Often Do Routine Eye Tests Miss Glaucoma?
More often than most people realise. Population-based studies in India, including large community studies in South India, have shown that glaucoma frequently remains undetected. This is true even in people who had already undergone cataract surgery. Cataract surgery improves vision but does not rule out glaucoma.
Across India, it is estimated that around 90% of glaucoma cases remain undiagnosed.
Even in developed countries, glaucoma diagnosis is difficult. Studies show both under-diagnosis and over-diagnosis are common. This is because glaucoma cannot be diagnosed from one test alone. It requires interpretation of patterns over time.
These numbers remind us that glaucoma is a subtle disease, not a simple one.
What a Proper Glaucoma Check Should Include
A structured glaucoma evaluation includes:
• optic nerve assessment
• OCT nerve fibre analysis
• visual field testing
• corneal thickness measurement
• angle examination
• risk stratification
• comparison over time
Because glaucoma is a slow disease, continuity of care matters more than a single visit.
Who Should Be Checked Even If Vision Is Normal
• Age above 40
• Family history of glaucoma
• High myopia
• Diabetes or hypertension
• Long-term steroid use
• Women caring for families who delay their own care
These groups need structured follow-up. This does not mean everyone with these risk factors needs glaucoma investigations. It means they need a comprehensive eye evaluation, with special focus on glaucoma.
Who Needs Glaucoma Investigations, and When?
Glaucoma testing is recommended whenever risk factors are present, even if vision feels normal. This includes people with a suspicious optic nerve appearance, ocular hypertension (eye pressure above 21 mmHg), thin corneas, a strong family history of glaucoma, or previous eye injury. Patients with high myopia, diabetes, or long-term steroid use also need evaluation. Because glaucoma is usually silent early, investigations should begin when these risk factors are first detected and be repeated at intervals based on individual risk so that subtle progression is not missed.
What Does “C:D Ratio” Mean?
The optic nerve has a small central hollow called the cup, surrounded by nerve tissue called the disc.
The cup-to-disc ratio (C:D) compares the size of this hollow to the whole optic nerve.
A C:D ratio greater than about 0.5, especially if it is increasing or the different between the two eyes is more than 0.2, can suggest possible nerve fibre loss and may need glaucoma testing.
However, C:D size varies naturally between people. Some individuals have large cups but healthy nerves. This is why the C:D ratio must always be interpreted along with OCT scans, visual field testing, and comparison over time. Numbers alone do not diagnose glaucoma, patterns do.

What Does “IOP > 21 mmHg” Mean?
IOP stands for intra-ocular pressure, the pressure inside the eye.
Pressures above 21 mmHg are considered higher than average. Ocular hypertension is defined as high eye pressures with no fucntional or structural damage to the optic nerve.
Not everyone with high pressure develops glaucoma, and some people develop glaucoma with normal pressure. But raised pressure increases risk and requires careful monitoring and sometimes treatment to protect the optic nerve.
Because glaucoma is usually invisible early, patients with ocular hypertension need structured follow-up even if vision is clear.
The Bigger Lesson
Early, consistent care prevents regret later. In glaucoma, we are not protecting eyesight today. We are protecting your vision for the rest of your life.
Healthcare systems are built around treating visible disease. Glaucoma is invisible early. So routine eye tests miss glaucoma. This is not anyone’s fault. But it means patients must ask questions and doctors must think long-term.
When a Second Opinion Helps
A second opinion is not about doubting your doctor. It is about understanding your own risk clearly.
Because glaucoma is subtle, a structured second opinion can be useful when:
• Reports are confusing
• Advised surgery suddenly
• Multiple drops started without explanation
• OCT and visual field results disagree
• Strong family history of glaucoma/ glaucoma blindness
A calm review of tests over time often clarifies risk.
The Importance of Serial Comparison
The most important glaucoma test is comparison.
We compare:
• OCT over years
• visual fields over years
• optic nerve photos
Progression becomes visible only in hindsight. That is why follow-up matters.
Common Misinterpretations
• Red OCT areas in high myopia
• Field defects from cataract
• Machine artefacts
• Ignoring early thinning
Patients should not panic. Or be falsely reassured, without explanation. A structured interpretation is essential to clarify, and stratify, risk.
My Approach
My approach to glaucoma evaluation begins with reviewing all prior reports in sequence: not just the most recent one. I look for patterns across OCT, visual field, and optic nerve imaging over time, because glaucoma progression only becomes visible when tests are compared, not read in isolation. Every patient receives a written risk summary and a clear explanation of what needs monitoring and why. I review all reports systematically with attention to long-term risk.
Closing Thought
Seeing clearly is not the same as seeing safely. In glaucoma, we are not protecting eyesight today. We are protecting your eyes for the rest of your life.
Early, consistent care matters more than dramatic late treatment.
Most patients who contact me are not yet sure they have glaucoma. That is exactly the right time to ask.
Read the research articles
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. This article was edited in April 2026.
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.
Available on Pubmed and Google Scholar
Dr Shibal Bhartiya
Glaucoma • Second Opinion • Advanced Care
www.drshibalbhartiya.com
+91 88826 38735
Read patient reviews on Google Business Profile
OCT and Visual Field
Understanding Glaucoma Investigations: OCT and Visual Field
OCT shows the structure of the optic nerve. Visual field tests show how vision is functioning. Patients struggle to understand why their doctor has reached a certain diagnosis, or treatment strategy. Many patients receive OCT and visual field reports full of colours and numbers. Both require careful interpretation, and an equally careful explanation. the truth is, your doctor is looking for a structure-function relationship, correlating it to your eye pressures, and the lifetime risk to your vision, and quality of life.
Glaucoma diagnosis is rarely based on one scan. Also glaucoma often has no symptoms. It requires understanding patterns over time: how the optic nerve looks, how visual fields change, how eye pressure behaves, and how your individual risk factors fit together.
OCT shows the structure of the optic nerve. Visual field tests show how vision is functioning.
Neither test alone can diagnose glaucoma. This is why reports sometimes seem confusing. A red area on OCT may be normal for a highly myopic eye. An abnormal visual field may simply reflect fatigue or cataract. On the other hand, subtle early glaucoma can be missed if reports are not compared carefully across months and years.
In glaucoma care, numbers do not treat disease. Understanding does.
My approach focuses on calm, structured interpretation of OCT and visual field reports so patients can make informed decisions about long-term eye health. Because glaucoma is usually invisible early, our goal is not only to see clearly today, but to protect vision safely ten years from now.
If your reports are confusing, conflicting, or leading to rushed treatment decisions, a structured glaucoma second opinion can help bring clarity.
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 1,500+ patient reviews on Google.
Understanding OCT
OCT measures thickness of nerve fibres. Red areas may indicate thinning.
But interpretation depends on:
• age
• myopia
• optic nerve size
• machine variability
• baseline comparison
One abnormal OCT does not prove glaucoma. But ignoring subtle changes can be dangerous.
Understanding Visual Fields
Visual field tests measure functional vision.
But results vary with:
• patient attention
• fatigue
• learning effect
• cataract
• dry eye
One abnormal field may not mean disease. Repeated patterns matter more when evaluating progression.
Why OCT and Visual Field Reports Must Be Interpreted Together

Glaucoma diagnosis needs both structure and function. OCT shows nerve structure. Visual field shows vision function. When both OCT and Visual Field show similar changes over time, diagnosis is stronger, and rooted in deeper evidence.
The Importance of Serial Comparison

The most important glaucoma test is comparison.
We compare:
• OCT over years
• visual fields over years
• optic nerve photos
Progression becomes visible only in hindsight. That is why follow-up matters.
Common Misinterpretations
• Red OCT areas in high myopia
• Field defects from cataract
• Machine artefacts
• Ignoring early thinning
You should not panic, or be falsely reassured. What you should ask for is a detailed explanation.
When to Seek Specialist Interpretation
• Conflicting reports
• Advice for surgery
• Multiple drops
• Normal pressure but abnormal OCT
• Strong family history
A structured interpretation can clarify risk.
My Approach
Reports are reviewed systematically with attention to long-term risk.
Patients receive:
• clear explanation
• risk assessment
• management options, including follow up schedule
• missing data list
Because glaucoma care is about continuity, and steady compliance with treatment.
⭐ FAQs – OCT and Visual Field Interpretation
1. My OCT report shows red areas. Does this mean I have glaucoma?
Not always. OCT compares your nerve thickness with an average database.
Red areas can appear in:
• high myopia
• large optic nerves
• normal anatomical variation
• machine artefacts
OCT is only one part of glaucoma diagnosis. It must be interpreted with visual fields, optic nerve exam, and follow-up over time.
2. My visual field test was abnormal once. Should I worry?
A single abnormal visual field does not confirm glaucoma. Visual fields depend on attention, fatigue, dry eye, cataract, and learning effect. Doctors usually repeat the test to confirm a pattern. Consistency over time matters more than one report.
3. Can OCT be normal but glaucoma still present?
Yes. No one test is infallible when it comes to glaucoma diagnosis.
Very early glaucoma can be missed on OCT, especially in normal-tension glaucoma or small optic nerves. This is why clinical examination and follow-up are important. Glaucoma diagnosis is a pattern seen over time, not one scan.
4. Can visual fields be normal if glaucoma is already present?
Yes. Structural nerve damage often occurs before functional loss. Patients may have normal visual fields but abnormal OCT or optic nerve appearance. Early detection focuses on protecting long-term vision before symptoms appear.
5. How often should OCT and visual field tests be repeated?
It depends on your risk of glaucoma progression or vision loss.
• Low risk: once a year
• Glaucoma suspect: every 6–12 months
• Established glaucoma: every 3–6 months
Your doctor decides based on progression risk. Regular comparison (and therefore, regular follow up) is the most important part of glaucoma care.
6. Why do my OCT numbers change between tests?
Small changes happen because of:
• machine differences
• scan alignment and test retest variability
• eye dryness
• cataract
• natural variation
Doctors thus look for consistent trends, not small fluctuations.
7. Can cataract affect visual field results?
Yes.
Cataract can cause diffuse depression on visual field testing. This may look like glaucoma but improves after cataract surgery. This is why reports must be interpreted carefully.
8. My eye pressure is normal. Why do I need OCT and Visual Field?
Many patients have normal-tension glaucoma. Pressure alone cannot rule out disease. OCT and visual field testing help detect subtle nerve damage. Glaucoma diagnosis needs multiple data points, eye pressure is only one of them.
9. Can glaucoma tests (OCT and Visual field) be wrong?
Tests are not “wrong,” but they can be misleading if taken in isolation. Machines measure data. Doctors interpret patterns. Also, visual fields can have fixation losses (you looked away from the fixation light), as well as false positives and false negatives. High rates of any of these can make your visual fields unreliable.
A structured review reduces unnecessary treatment and dangerous delay.
10. When should I seek a glaucoma second opinion?
Consider a second opinion if:
• You are advised surgery suddenly
• Reports are confusing
• Multiple drops are started without explanation
• OCT and visual field results disagree
• Strong family history exists
Clarity helps you make calm, informed decisions.
11. What is the most important glaucoma test?
The most important test is comparison over time. Glaucoma progression becomes visible only when reports are compared across months and years. Continuity of care is essential, and one all clear diagnosis does not mean you don’t need a follow up visit.
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.
12. Can glaucoma be cured if detected early?
Glaucoma cannot be reversed. But early detection and regular care can preserve useful vision for life. The goal is not perfect tests today, but safe vision ten years from now, and always.
Closing Thought
Numbers do not treat glaucoma.
Understanding does.
Protecting vision requires careful interpretation over time.
If you would like your OCT or visual field reports reviewed in a structured glaucoma second opinion:
📞 +91 88826 38735
🌐 drshibalbhartiya.com
Second Opinion Form for teleconsults
Related Reading
- Why Do I Need a Visual Field Test?
- Understanding Your OCT Report in Glaucoma
- Visual Field and OCT: Structure & Function Correlation
- Glaucoma Diagnosis in Gurgaon
- Glaucoma Progression: What It Means and How to Slow It
- Get a Glaucoma Second Opinion in Gurgaon
- Get an Online Glaucoma Consult
Read the research articles
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. This article was updated in April 2026.
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.
Access her work on Pubmed, Google Scholar, ResearchGate and ORCID.
Dr Shibal Bhartiya
Glaucoma • Second Opinion • Advanced Care
www.drshibalbhartiya.com
+91 88826 38735
1500+ Five Star Patient Reviews Google Business Profile
Upload your reports for a structured review.
For people unable to come to Dr Bhartiya’s clinic: Read more about teleconsultation for glaucoma
Glaucoma Diagnosis in Gurgaon
Glaucoma Diagnosis in Gurgaon: What to expect
Glaucoma steals vision silently. Most patients feel no pain and notice no changes, until significant nerve damage has already occurred.
Early diagnosis changes everything. In, Gurgaon, Dr. Shibal Bhartiya offers a complete glaucoma diagnostic workup using advanced imaging and functional testing.
If you have a family history of glaucoma, are over 40, or have been told your eye pressure is high, this page explains exactly what your evaluation involves.
Why Early Glaucoma Detection Matters
Vision lost to glaucoma cannot come back. But when you catch it early, treatment halts further damage. That is why a thorough diagnostic evaluation is essential, not optional.
Early detection matters most if you have:
- A parent, sibling, or child with glaucoma (family history)
- Eye pressure above the normal range
- Thin corneas are a known risk factor
- Diabetes, high myopia, or a history of eye injury
- Age over 40, especially with South Asian ancestry
💡 Research shows that South Asians have a higher risk of angle-closure glaucoma. A screening examination can identify this risk before any symptoms appear.
7 Tests Used to Diagnose Glaucoma
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 1,500+ patient reviews on Google.
Dr. Bhartiya uses a structured, evidence-based protocol. Each test answers a different question about the health of your optic nerve and visual system.
1. Intraocular Pressure (IOP) Measurement
High eye pressure is the most well-known glaucoma risk factor. Dr. Bhartiya measures IOP using Goldmann applanation tonometry, the gold-standard technique.
Normal IOP: 10–21 mmHg. Readings above this range trigger further evaluation. However, some patients develop glaucoma at normal pressures (normal-tension glaucoma), so IOP alone is never enough.
The test is quick and painless. It takes less than a minute per eye.
💡 IOP fluctuates through the day. Dr. Bhartiya may check your pressure at different times if she suspects normal-tension glaucoma.
2. OCT- Optic Nerve and RNFL Imaging
Optical Coherence Tomography (OCT) is the most important advance in modern glaucoma diagnosis. It gives Dr. Bhartiya a detailed cross-sectional scan of your optic nerve and retinal nerve fibre layer (RNFL).
OCT detects structural nerve damage up to 6 years before visual field loss becomes visible. This makes it the cornerstone of early detection.
OCT measures:
- RNFL thickness, thinning here signals glaucoma damage
- Optic nerve head parameters, including the cup-to-disc ratio
- Ganglion cell complex, a sensitive early marker of nerve loss
The scan is non-contact, takes about 5 minutes, and requires no eye drops in most cases.
💡 Dr. Bhartiya’s research background in optic nerve imaging means she reads OCT results with particular depth, looking beyond the machine’s colour codes and interpreting the raw data.
3. Visual Field Testing (Perimetry)
Glaucoma damages peripheral vision first. A visual field test maps exactly which parts of your vision are affected, and how severely. You sit in front of a dome-shaped screen and press a button each time you see a light flash. The test takes 5–7 minutes per eye.
Visual field testing answers three questions:
- Is there functional vision loss, and where?
- How fast is the damage progressing?
- Is current treatment working?
Results compare against age-matched norms. Serial testing over time is especially important, a single test shows the current state; repeated tests reveal the trend.
💡 Reliable results require full concentration. Bhartiya’s team explains the test carefully so your first attempt is accurate. But if there are too many false positives or negatives, they will request a repeat!
4. Corneal Pachymetry
Pachymetry measures the thickness of your cornea. This single measurement significantly changes how Dr. Bhartiya interprets your eye pressure.
Here is why. IOP measurements are affected by corneal thickness. A thin cornea makes pressure read falsely low. A thick cornea makes it read falsely high.
Average corneal thickness: ~545 microns. Corneas below 500 microns carry a significantly higher risk of glaucoma progression, even when IOP appears normal.
The test is painless and takes under 2 minutes. A small probe touches the cornea gently after numbing drops.
💡 Pachymetry is especially important if glaucoma is progressing despite treatment, and for patients with borderline IOP readings.
5. Gonioscopy: Examining the Drainage Angle
Gonioscopy is the only way to directly examine the drainage angle of the eye, where fluid exits. This examination determines whether your glaucoma is open-angle or angle-closure. That distinction drives every treatment decision.
Dr. Bhartiya places a specialised mirrored lens gently on your eye (after numbing drops) to visualise structures that are otherwise invisible.
Gonioscopy reveals:
- Open-angle glaucoma: the drainage angle is open but not working efficiently
- Angle-closure glaucoma: the angle is narrow or blocked, often needing laser treatment
- Secondary causes: such as steroid use, pigment dispersion, pseudoexfoliation, or neovascularisation
💡 Many patients in India have narrow drainage angles without knowing it. Gonioscopy at your first visit can prevent a potentially blinding acute angle-closure attack.
6. Diurnal IOP Monitoring and the Water Drinking Test
Eye pressure is not constant. It fluctuates throughout the day and night, typically peaking around 4 AM and varying by as much as 6–8 mmHg over 24 hours. A single pressure reading in clinic captures only one moment in that cycle.
This matters because peak IOP, not average IOP, is what damages the optic nerve. A patient whose pressure appears well-controlled at a morning clinic visit may have dangerously high peaks overnight.
24-hour IOP monitoring records pressure every two hours over a full day and night. It is the most comprehensive method but is cumbersome and expensive. It is reserved for complex cases where standard clinic measurements are insufficient.
The Water Drinking Test is a practical alternative. Eye pressure is measured at baseline, then you drink approximately 10 ml per kg body weight of water over five minutes. Pressure is then recorded every 15 minutes for one hour. The test gives a reasonable estimate of peak IOP, pressure fluctuation, and how quickly your eye recovers to baseline.
If a water drinking test has been scheduled, carry a one-litre bottle of water. There are no other specific preparations.
💡 Dr Bhartiya has published peer-reviewed research on 24-hour IOP monitoring, target IOP, and continuous pressure recording in glaucoma patients. This is an area of active clinical research at this practice.
7. Optic Disc Photography
A high-resolution photograph of your optic nerve is taken and stored in your record. This image becomes one of the most important documents in your long-term glaucoma care.
The reason is straightforward. Glaucoma causes slow, progressive changes to the optic disc — changes that are often difficult to detect at any single visit. A photograph taken today gives your doctor a precise baseline to compare against at every future visit. Subtle changes that would otherwise go unnoticed become visible when images from different years are placed side by side.
Disc photography requires no drops in most cases. You sit in front of a fundus camera, look at a fixation target, and a bright flash takes the image. It takes under two minutes.
💡 Serial disc photography over years is one of the most powerful tools for detecting glaucoma progression — and one of the most underused in routine practice.
What to Expect at Your Glaucoma Evaluation
A complete glaucoma workup takes approximately 60–90 minutes. Here is the sequence:
- Brief history: symptoms, family history, current medications
- Visual acuity and refraction
- IOP measurement (both eyes)
- Pachymetry
- Gonioscopy
- Dilated fundus examination and optic nerve evaluation
- OCT imaging
- Visual field testing (where indicated)
- Detailed consultation: results, diagnosis, and treatment options
Dilation drops may be used during the examination. Your vision may be blurred for 3–4 hours afterwards. Plan not to drive yourself home.
Seeking a Second Opinion on Glaucoma?
Many patients come to Dr. Bhartiya after receiving a diagnosis elsewhere, unsure whether they need surgery, or concerned about a treatment recommendation.
A second opinion review includes a full re-evaluation of all existing tests, a fresh examination, and an honest, unhurried discussion of your options. Dr. Bhartiya brings her research expertise to every such case.
💡 Bring all previous reports, OCT scans, visual field printouts, and prescription history. The more information you bring, the more specific the guidance.
Book Your Glaucoma Diagnosis in Gurgaon
Do not wait for symptoms. Glaucoma gives no warning until significant damage is done.
Book a comprehensive glaucoma evaluation with Dr. Shibal Bhartiya at Gurgaon.
📞 Call or WhatsApp: +91 8882638735
🔗 Also read: Glaucoma Surgery in Gurgaon | Glaucoma Second Opinion | About Dr. Shibal Bhartiya
Frequently Asked Questions
Is glaucoma diagnosis painful?
No. All five tests are painless. IOP measurement, OCT, and visual field testing involve no contact with the eye. Pachymetry and gonioscopy use numbing drops first, so you feel minimal discomfort.
How often should I get screened?
If you have risk factors — family history, high eye pressure, thin corneas, or age over 40 — annual screening is advisable. For diagnosed patients, Dr. Bhartiya sets a personalised review schedule based on disease stage and stability.
My eye pressure is normal. Can I still have glaucoma?
Yes. Normal-tension glaucoma is well-recognised and common in Asian populations. Dr. Bhartiya evaluates optic nerve structure and visual function alongside IOP — because pressure alone does not tell the whole story.
Can glaucoma be detected before symptoms appear?
Yes, and this is the entire point of a diagnostic evaluation. OCT detects structural nerve damage years before you notice any visual change. Early detection is the single most important factor in protecting your long-term vision.
What is the difference between open-angle and angle-closure glaucoma?
Open-angle glaucoma develops slowly and painlessly as drainage channels lose efficiency over time. Angle-closure glaucoma occurs when the drainage angle narrows or blocks — it can cause sudden pain, redness, and rapid vision loss. Gonioscopy distinguishes between the two and guides treatment.
How long does the full diagnostic evaluation take?
Approximately 60–90 minutes for a first-visit comprehensive workup. Follow-up visits for monitoring are usually shorter, 30–45 minutes.
How should I prepare for my glaucoma tests?
No specific preparation is needed. A few things will help:
Read a little about glaucoma beforehand and write down any questions you want to ask. Get a good night’s sleep before your visual field test, fatigue significantly affects results. Have a light meal before you arrive, as some tests take time. Continue all previously prescribed medications unless told otherwise.
If a water drinking test has been scheduled, carry a one-litre bottle of water. If dilation has been planned, arrange for someone to drive you home, your vision may be blurred for 3–4 hours after dilating drops. Bring something to read while you wait. Glaucoma investigations are painless, but they are time-consuming.
I have been advised gonioscopy. What does it involve?
Gonioscopy is used to examine the drainage angle of your eye, the area where fluid exits. It determines whether your glaucoma is open-angle or angle-closure, which drives every treatment decision.
Your doctor will apply numbing drops first, so the procedure is painless. A small mirrored lens is then placed gently on the eye. You will be asked to look in a specific direction while the doctor examines the angle with the slit lamp. The room lights are usually dimmed for better visibility.
Most people tolerate gonioscopy well. Occasionally, the procedure stimulates the vagus nerve and causes brief dizziness, this passes quickly. The whole examination takes a few minutes.
The visual field test sounds difficult. Any tips?
It is one of the harder tests to do well, but a few things help.
You will sit in front of a dome-shaped screen and press a button each time you see a flash of light. Keep looking at the central fixation light throughout, do not track the flashes. Press the button even if you are only partially sure you saw something.
Pace yourself. If you feel fatigued, tell the operator and take a break. If your eyes feel dry, blink or use your lubricant drops before continuing. Do not rush, pressing quickly to finish the test produces unreliable results and may mean you need to repeat it.
There is a learning curve. Your doctor may ask you to repeat the test at a subsequent visit, this is normal and not a cause for concern.
How is eye pressure measured?
The standard method is Goldmann applanation tonometry. Your doctor applies numbing drops and a small amount of orange dye, then brings a probe into gentle contact with the cornea. The test is painless and takes under a minute per eye.
Some clinics use a non-contact tonometer, the air-puff machine, which requires no drops and no contact. Both methods are accurate when performed correctly.
How does the doctor examine my optic nerve?
The optic nerve sits at the back of the eye and cannot be seen without special equipment. Your doctor will use one of two methods: an ophthalmoscope (a handheld light and lens), or a high-powered lens at the slit lamp. Dilating drops are often used to widen the pupil and allow a clearer view.
What the doctor looks for is the size and shape of the optic cup relative to the disc (the cup-to-disc ratio), the colour and rim tissue of the nerve, and any asymmetry between the two eyes. These findings, combined with OCT and visual field data, form the basis of diagnosis.
Read the research articles
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. This article was edited in April 2026.
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.
Available on Pubmed and Google Scholar
Dr Shibal Bhartiya
Glaucoma • Second Opinion • Advanced Care
www.drshibalbhartiya.com
+91 88826 38735
Patient reviews Google Business Profile