Most people assume their vision is intact. If you can read messages, recognise faces and move through familiar spaces without difficulty, there’s no reason to question it.
Glaucoma challenges that assumption. It develops gradually, often without pain or disruption to central vision, and daily life continues as usual even as the outer edges of sight begin to narrow. By the time something feels noticeably different, part of that vision may already be permanently lost.
Why glaucoma so often goes unnoticed
Glaucoma refers to a group of eye conditions that damage the optic nerve, which carries visual information from the eye to the brain. In many cases, this is associated with increased pressure inside the eye, although it can also occur when pressure appears within a typical range.
What makes glaucoma difficult to detect early isn’t just the condition itself, but how it progresses. There’s no clear starting point. Changes tend to begin at the periphery and move inward over time, while central vision remains largely intact, allowing people to continue with daily tasks without difficulty.
The brain also adapts by filling in small gaps in vision. These shifts are easy to overlook because they don’t interrupt daily life in obvious ways and are rarely noticed as a problem.
Dr Nandini, an ophthalmologist who specialises in glaucoma, explains that glaucoma is often called the “silent thief of sight” because in its early stages it usually causes no pain and no obvious symptoms. As a result, many people assume their eyes are healthy when their vision still seems normal.
The early signs can be subtle and easily overlooked. These may include:
- Gradual loss of side (peripheral) vision, usually affecting both eyes
- Difficulty noticing objects approaching from the side
- Subtle problems with contrast or seeing clearly in dim lighting
- Increased glare or slower adaptation to darkness in some individuals
Because the brain often compensates for early vision loss, most people don’t realise anything is wrong until the disease has progressed. This is why regular eye examinations are important, even when vision appears perfectly normal.
She also notes that people with a family history of glaucoma, high eye pressure, those over the age of 40, or people of African, Asian, and Hispanic descent, as well as those with high myopia or hypermetropia, may benefit from regular eye checks, as glaucoma can develop gradually without noticeable warning signs.
What early changes can look like in everyday life
These are usually subtle shifts in how you experience your surroundings. When symptoms do appear, they are often difficult to describe. Many people don’t recognise them as vision-related at first, and they are easily attributed to fatigue, ageing or prolonged screen use, which are common in many urban environments.
They may sound like this:
- “I didn’t notice someone approaching from my side.”
- “I feel less confident walking in dim lighting.”
- “Night driving feels more uncomfortable than before.”
- “Bright lights seem more glaring, especially when I’m tired.”
- “I sometimes miss things unless I turn my head fully.”
These signs are often linked to changes in peripheral (side) vision, which is typically affected first in glaucoma.
Rather than waiting for vision to feel worse, it can be more useful to notice how you move through your surroundings. Are you turning your head more often to check what’s around you? Missing movement at the edges of your vision? Feeling less confident in low light? These signs often appear before anything feels like a clear problem.
Often, it isn’t the individual but someone close to them who notices a shift first. A family member may observe small changes, such as pausing before stepping off a curb, misjudging movement in crowded spaces, or scanning their environment more deliberately. Over time, these adjustments may point to reduced awareness of what’s happening around them, not just changes in vision.
For caregivers, this creates a practical challenge. The signs can be easy to second-guess, but important not to ignore.
If you notice these signs, it’s worth arranging an eye check even if your vision still feels largely normal. Glaucoma can’t be confirmed based on symptoms alone, and waiting for clearer signs may delay detection.
Why diagnosis often happens late
Across many parts of Asia, healthcare is still largely reactive. If nothing feels wrong, it’s natural to assume everything is fine.
Glaucoma challenges that instinct. Because vision often feels stable for a long time, there’s little reason to question it. It’s usually only when changes begin to affect how you navigate unfamiliar environments or respond to movement around you that something feels different.
By then, the condition is often already established.
In screen-heavy, high-pressure lifestyles where visual fatigue is common, subtle visual differences are easily dismissed as fatigue rather than investigated further. This overlap can delay when people seek evaluation.
When eye pressure is not the full story
Glaucoma is often associated with high eye pressure, but that’s only part of the picture. Some people develop optic nerve damage even when their eye pressure falls within what’s considered a normal range. This form, often referred to as normal-tension glaucoma, reflects a combination of factors such as blood flow, nerve sensitivity and individual susceptibility.
Glaucoma can still develop even in people whose eye pressure falls within the normal range, a form often referred to as normal-tension glaucoma. In these cases, damage to the optic nerve may occur because the nerve is more vulnerable to pressure, or due to factors such as reduced blood flow to the optic nerve or other structural differences of the eye.
This means that normal eye pressure doesn’t rule out glaucoma. Diagnosis relies on a combination of clinical assessments, including measurement of eye pressure, careful examination of the optic nerve, and visual field testing to detect early changes in peripheral vision.
For this reason, periodic comprehensive eye examinations are important and shouldn’t be limited to simple vision tests.
General recommendations include:
- Before age 40: At least one baseline comprehensive eye examination, especially if risk factors are present.
- From age 40–60: A comprehensive eye examination every 2–4 years.
- After age 60: Eye examinations every 1–2 years, as the risk of glaucoma increases with age.
Importantly, good vision doesn’t rule out glaucoma. Many people diagnosed in the early stages have no visual complaints at all, which is why regular eye checks remain an important part of protecting long-term eye health.
Who may be at higher risk
Understanding this pattern also changes how we think about risk. Glaucoma can affect anyone, but some groups may benefit from more regular monitoring:
- Adults over the age of 40
- Individuals with a family history of glaucoma
- People with diabetes or high blood pressure
- Those who have previously been told they have higher eye pressure
- Individuals using steroid medications over prolonged periods
Adults over the age of 40
Individuals with a family history of glaucoma
People with diabetes or high blood pressure
Those who have previously been told they have higher eye pressure
Individuals using steroid medications over prolonged periods
Certain populations, including people of Asian descent, may also have a higher prevalence of specific types such as normal-tension glaucoma.
In many Asian contexts, family health history isn’t always openly discussed or well documented, so conditions may only become visible when they’re more advanced. This makes risk harder to recognise, even within the same household.
Glaucoma risk isn’t the same for everyone, and certain groups may benefit from earlier or more frequent screening, even if they have no symptoms.
People who may require closer monitoring include:
- Those with a family history of glaucoma, particularly affected parents, siblings, or close relatives
- Individuals of African or Afro-Caribbean descent, who are more likely to develop glaucoma at a younger age and may experience faster progression
- People of Asian ethnicity, who have a higher risk of certain forms such as angle-closure glaucoma
- Adults over the age of 40, with risk increasing further after 60
- Individuals with high eye pressure, thin corneas, or significant near-sightedness (myopia)
- People with systemic conditions such as diabetes, vascular disease, or blood pressure dysregulation
For these groups, relying on symptoms isn’t advisable because glaucoma often develops without noticeable warning signs in the early stages. Targeted screening and personalised follow-up intervals play an important role in detecting the condition early and managing it effectively.
Why everyday habits can make symptoms easier to miss
In modern urban life, screen use, sleep patterns and prolonged sedentary behaviour shape how we experience visual fatigue.
These habits don’t directly cause glaucoma, but they can shape how symptoms are noticed and interpreted. When tired eyes, glare and discomfort are part of daily life, it becomes harder to distinguish between what feels typical for you and what may need to be checked. This is where lifestyle habits can mask early warning signs.
Everyday habits such as screen use, posture, and sleep aren’t considered direct causes of glaucoma, but they may influence eye pressure and overall eye health, which can be relevant for people who already have the condition or are at higher risk, explains Dr Nandini.
Prolonged screen time itself doesn’t cause glaucoma. However, extended periods of close-up work and reduced blinking can lead to eye strain and dryness, which may make visual discomfort more noticeable even though these effects aren’t linked to optic nerve damage.
Posture can also affect temporary changes in eye pressure. For example, positions where the head is placed lower than the body for extended periods may increase intraocular pressure in some individuals. This is one reason patients with glaucoma are sometimes advised to be mindful of prolonged head-down or inverted positions, such as those adopted during certain yoga postures or similar activities.
Sleep patterns may also influence eye pressure. Some studies suggest that sleep position and nocturnal blood flow to the optic nerve could affect glaucoma progression in susceptible individuals. For example, consistently sleeping on one side may expose that eye to slightly higher pressure over time.
Overall, regular eye examinations and adherence to prescribed treatment remain the most important factors in managing glaucoma risk and progression. Lifestyle habits can support general eye health, but they shouldn’t replace proper medical monitoring.
How to describe what you are noticing to your doctor
One of the biggest challenges isn’t recognising symptoms, but explaining them clearly.
Many people default to saying, “My vision seems fine,” which may not reflect small but noticeable differences in how they see or respond to their surroundings.
A more useful approach is to describe specific situations:
- “I’ve started turning my head more to check my surroundings.”
- “I feel less aware of things happening beside me.”
- “I’m more cautious walking in unfamiliar places.”
- “Night driving feels different, but I can’t quite explain how.”
It can also help to mention when you first noticed these changes and whether they have been getting more frequent or noticeable over time. Many of these experiences relate to changes in peripheral (side) vision, which may not be obvious during everyday tasks like reading.
These observations help your doctor understand how your vision works in everyday situations, beyond what standard charts can capture. In many cases, this starts with a comprehensive eye check with an optometrist, who can assess your vision and refer you to an ophthalmologist, a medical eye specialist, if further evaluation is needed.
Making the most of your eye check
Asking a few focused questions during an eye check can help you understand what the findings mean and what to look out for between visits.
You can consider asking:
These questions help shift the consultation from d a routine check to a more informed discussion about risk, monitoring and next steps.
A routine eye examination may include measuring eye pressure (tonometry), assessing the optic nerve, and tests such as visual field testing to detect gaps in peripheral vision. These typically quick and non-invasive, involving a combination of imaging, pressure measurement and visual response assessments.
The biggest misconception about glaucoma is the belief that “if my vision is good, my eyes are healthy.” This misunderstanding often delays diagnosis because glaucoma can cause irreversible damage to the optic nerve long before noticeable vision changes occur, says Dr Nandini. As a result, many people only seek medical attention once significant sight loss has already developed.
Addressing this misconception requires a broader community effort. This includes:
- Shifting the message from simple vision testing to comprehensive eye evaluations, based on best practice guidelines that focus on identifying the early features of glaucoma before vision is affected.
- Encouraging routine eye examinations as part of general health care, similar to checks for blood pressure or diabetes.
- Using clear, accessible language to explain that glaucoma is manageable but not curable, and that treatment is most effective when the condition is detected early.
- Supporting awareness initiatives, such as World Glaucoma Week (held every March) and Glaucoma Awareness Month (January), which help highlight the importance of screening and education.
Early diagnosis does more than preserve vision. It helps protect independence, quality of life, and confidence. Strengthening awareness, education, and access to screening remains one of the most effective ways to reduce preventable vision loss from glaucoma.
Glaucoma is often picked up on a test, not because something feels wrong. Most people don’t notice the change. They adjust to it as it happens, often without realising what’s been lost.
When was your last eye check, and what was it actually assessing?
Dr Nandini Sankaranarayanan, UAE
Specialist Ophthalmologist,
Glaucoma Specialist and Cataract Surgeon,
Medcare Eye Centre, Dubai
Instagram @eyedoctornandini
This article was produced by Healthful For You. The views and opinions expressed throughout are those of the authors and do not necessarily reflect those of the Expert Contributor. The Expert Contributor has provided input solely for the EXPERT INSIGHT and TIP segments, based on their professional expertise. These comments are intended to offer general guidance and may not apply to all individuals. Any interpretations or conclusions beyond that section are those of Healthful For You. This article is not a substitute for personalised medical advice, diagnosis, or treatment. Please consult your doctor or a healthcare professional regarding your specific health needs.
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