Everything You Need to Know About Glaucoma
Glaucoma is one of the world’s leading causes of blindness, silently affecting millions without warning. This sneaky condition often goes unnoticed in its early stages, gradually damaging the optic nerve, which is the vital highway that carries visual information from your eyes to your brain. Left unchecked, glaucoma can lead to permanent vision loss, making early detection and intervention absolutely essential to preserve your sight.
This blog aims to provide essential knowledge about Glaucoma causes and symptoms, the latest treatments, and prevention, helping you protect your eye health from this sight-threatening condition.
What is glaucoma and its causes?
Glaucoma is a group of eye diseases characterised by damage to the optic nerve, often connected to increased intraocular pressure (IOP)—the pressure inside the eye. Since the optic nerve is crucial for transmitting visual signals to the brain, any damage can severely impact vision.
A 2023 study estimates glaucoma prevalence in adults aged 40 and above in India to be between 2.7% and 4.3%. By 2040, glaucoma is expected to affect an additional 27.8 million people in Asia, with India and China bearing the highest burden. It currently causes 5.5% of total blindness in India, affecting 1.2 million people.
The main cause of glaucoma is ocular hypertension, where improper drainage of the eye's fluid (aqueous humour) leads to increased pressure. However, some types of glaucoma can develop even with normal IOP, and the exact cause in these cases remains unclear.
What are the risk factors for glaucoma?
The risk factors for glaucoma may include poor blood flow to the optic nerve or structural weaknesses. Here are some of the risk factors for glaucoma:
- Age: The risk increases with age.
- Family history: A family history of glaucoma increases the likelihood.
- Ethnicity: People of African or Asian descent are more prone.
- Health conditions: Diabetes and hypertension can raise the risk.
- Eye injuries: Previous eye trauma can increase vulnerability.
- Corticosteroid use: Long-term use of corticosteroid medications may elevate the risk.
What are the symptoms of glaucoma?
One of the primary concerns with glaucoma is that it often develops slowly and painlessly, with symptoms not noticeable until the condition is quite advanced. Early signs of glaucoma are subtle, which is why routine eye exams are essential, particularly if you’re at a higher risk. Common glaucoma symptoms include:
- Gradual loss of peripheral (side) vision
- Blurred or tunnel vision in later stages
- Seeing halos around lights
- Sudden vision loss or eye pain (more common in acute angle-closure glaucoma)
The lack of noticeable symptoms in the early stages is why it’s usually referred to as the "silent thief of sight." Without regular eye exams, many people are unaware they have the condition until notable vision loss has already occurred.
What are the different types of glaucoma?
There are many types of glaucoma, each with different causes, symptoms, and management strategies. The most common types include:
Type of Glaucoma | Description | Signs and Symptoms |
Open-Angle Glaucoma | This is the most common form of glaucoma, where the drainage angle between the cornea and iris remains open, but the trabecular meshwork becomes clogged, leading to increased intraocular pressure (IOP). | No noticeable symptoms in the early stages, gradual loss of peripheral vision over time. Often detected during eye exams. |
Angle-Closure Glaucoma | Occurs when the iris is too close to the drainage angle, blocking fluid drainage and increasing IOP. It causes sudden and severe symptoms. | Severe eye pain, headache, nausea, vomiting, blurred vision, halos around lights, red eyes. Immediate treatment is required. |
Normal-Tension Glaucoma | Optic nerve damage occurs despite normal intraocular pressure. The cause is not fully understood but may involve poor blood flow to the optic nerve. | Progressive vision loss (mainly peripheral vision), no noticeable symptoms in early stages. |
Congenital Glaucoma | A rare form present at birth, caused by abnormal development of the eye’s drainage system. | Eye enlargement, light sensitivity, excessive tearing, cloudiness in the cornea, and in severe cases, vision loss if untreated. |
How to diagnose glaucoma?
The diagnosis of glaucoma involves a comprehensive eye exam performed by an eye care professional, typically an optometrist or ophthalmologist. Here are some of the common glaucoma diagnosis methods:
- Eye Pressure Test (Tonometry): This measures the intraocular pressure (IOP) to determine whether it’s elevated. Elevated IOP is a primary indicator of glaucoma, though it doesn’t necessarily mean a person has the condition.
- Optic Nerve Assessment: The optic nerve will be examined for signs of damage. This can be done using imaging techniques such as optical coherence tomography (OCT) or by inspecting the optic disc (the part of the eye where the optic nerve connects to the retina).
- Visual Field Test: This checks for loss of peripheral vision, which is one of the first signs of glaucoma. A computerised test is commonly used to map out the patient’s field of vision.
- Pachymetry: This measures the thickness of the cornea, as a thicker or thinner cornea can affect IOP readings and may influence the diagnosis of glaucoma.
If glaucoma is diagnosed, your healthcare provider will discuss possible treatment options based on the severity and type of glaucoma.
What are the best treatments for glaucoma?
While there is no cure for glaucoma, there are several glaucoma treatment options available to help manage the condition and prevent further vision loss. The goal of treatment is to lower intraocular pressure (IOP) to levels that reduce the risk of optic nerve damage.
1. Glaucoma eye drops and medication: The most common form of treatment for glaucoma is medication, typically in the form of eye drops. These medications work by either reducing the production of aqueous humour (the fluid in the eye) or improving its drainage. Common classes of eye drops include:
- Prostaglandin analogs
- Beta-blockers
- Alpha agonists
- Carbonic anhydrase inhibitors
2. Oral medications: In some cases, oral medications such as carbonic anhydrase inhibitors may be used to lower IOP.
3. Laser therapy: Laser treatments can be used to improve drainage in the eye or reduce fluid production. Common types of laser therapy include:
- Laser trabeculoplasty: Often used for open-angle glaucoma to improve fluid drainage.
- Laser iridotomy: Recommended for angle-closure glaucoma to create a new drainage pathway for fluid.
4. Surgical Intervention: For advanced glaucoma or cases where other treatments have been unsuccessful, surgery may be necessary. The most common surgical procedure is a trabeculectomy, which creates a new drainage pathway for the fluid. Newer surgical options, such as minimally invasive glaucoma surgery (MIGS), offer less risk and quicker recovery times.
5. Implantable devices: Another latest treatment for glaucoma is glaucoma drainage devices (shunts), which are surgically implanted to help drain fluid from the eye, lowering IOP. These devices are especially useful in cases where other treatments have failed or for patients with severe glaucoma.
How to prevent glaucoma?
While it may not be entirely possible to prevent glaucoma, there are steps you can take to reduce your risk and protect your vision.
Glaucoma management is key to preventing further damage and preserving your eyesight. Here are some practical tips:
- Get regular eye exams: Especially if you are over 40 or have risk factors such as a family history of glaucoma, high blood pressure, or diabetes.
- Maintain a healthy lifestyle: By managing your blood pressure, avoiding smoking, and eating a balanced diet rich in antioxidants, which may help protect your optic nerve.
- Manage eye health: Use protective eyewear during activities that could cause eye injury, and seek medical advice if you experience any vision changes.
- Take medications as prescribed: Consistently use glaucoma medications, including eye drops, even if you don’t experience symptoms. Skipping doses can lead to an increase in IOP and damage to the optic nerve.
- Be aware of early signs: Symptoms such as changes in peripheral vision or seeing halos around lights, and seek immediate medical help if you experience any sudden changes in vision.
Expert’s opinion on glaucoma:
Dr Ronnie Jacob George, director (of the glaucoma department) at Sankara Nethralaya Hospital, Chennai, and director of the Medical Research Foundation, said, “It is important for those in their 40s and above to get regular eye check-ups once every year. If the pressure is high, vision loss can happen within months. Otherwise, it can take nine to ten years.”
Dr Soundari S, Regional Head-Clinical Services at Dr Agarwals Eye Hospital, Chennai, said, “There are also glaucoma drainage devices. These devices have shown successful IOP control in complicated glaucomas like neovascular glaucoma, uveitic glaucoma and previously failed trabeculectomy.” She also added, “The choice of treatment, depending on the type and severity of glaucoma, includes medication, laser therapy and surgical intervention.”
Frequently Asked Questions
1. What are the don'ts when you have glaucoma?
When you have glaucoma, avoid skipping your prescribed medication, as it can increase eye pressure and damage the optic nerve. Don’t engage in activities that could injure your eyes, and avoid taking medications that could raise intraocular pressure, such as certain steroids.
2. What are the 5 stages of glaucoma?
The five stages of glaucoma begin with normal IOP, where no damage occurs. In early-stage glaucoma, increased IOP shows no symptoms. Moderate glaucoma sees peripheral vision loss, while advanced glaucoma results in significant impairment. In end-stage glaucoma, severe optic nerve damage leads to blindness. Timely treatment is essential for vision loss prevention and to stop the progression of blindness.
3. What are the worst foods for glaucoma?
A 2018 NIH study stated that high levels of caffeine, sodium, and sugar can significantly increase intraocular pressure (IOP), leading to a worsening of glaucoma. As a result, foods such as caffeinated beverages, high-sodium foods, sugary snacks, trans fats, and excessive alcohol should be avoided to help manage the condition and support overall eye health.
4. What is usually the first sign of glaucoma?
The first sign of glaucoma is usually a gradual loss of peripheral vision, often without noticeable symptoms. Since glaucoma can progress silently, early detection is crucial for glaucoma and blindness prevention. Regular eye exams are essential for monitoring and managing the condition.
5. What are the natural remedies for glaucoma management?
Natural remedies for glaucoma management include consuming a diet rich in antioxidants, such as leafy greens and omega-3 fatty acids, which may support overall eye health. Regular exercise can also help lower intraocular pressure (IOP), but always consult a doctor before stopping prescribed treatments.
Wrapping up
Glaucoma is a serious eye condition that can lead to permanent vision loss if left untreated. Early detection through regular eye exams and proper management can help prevent significant damage to the optic nerve. By staying informed, adhering to prescribed treatments, and adopting a healthy lifestyle, you can protect your eyesight and reduce your risk of glaucoma.
"An ounce of prevention is worth a pound of cure." – Benjamin Franklin
Also, read our other articles on eye health:
1. Frequently Asked Questions About Glaucoma
2. Debunking The Common Myths About Glaucoma
3. All You Need To Know About Conjunctivitis (Pink Eye)
4. Are You At Risk Of Eye Floaters?
References
1. Dietze J, Blair K, Zeppieri M, et al. Glaucoma. [Updated 2024 Mar 16]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK538217/
2. https://www.nei.nih.gov/learn-about-eye-health/eye-conditions-and-diseases/glaucoma
3. Wagner IV, Stewart MW, Dorairaj SK. Updates on the Diagnosis and Management of Glaucoma. https://pmc.ncbi.nlm.nih.gov/articles/PMC9673042/
4. Hollands H, Johnson D, Hollands S, Simel DL, Jinapriya D, Sharma S. Do findings on routine examination identify patients at risk for primary open-angle glaucoma? The rational clinical examination systematic review. https://pubmed.ncbi.nlm.nih.gov/23677315/
5. Al Owaifeer AM, Al Taisan AA. The Role of Diet in Glaucoma: A Review of the Current Evidence. https://pmc.ncbi.nlm.nih.gov/articles/PMC5997592/