An Eye Specialist’s Guide to Glaucoma

If it’s not treated in time, glaucoma can cause you to lose vision and even irreversible blindness. So what is the cause and how can we prevent it?

1. Glaucoma is often referred to as the ‘silent thief of sight’

Glaucoma is a specific group of diseases that damages the eye’s optic nerve. It is known as the ‘Silent Thief of Sight’ because many people with glaucoma experience no early symptoms or pain. In fact, more than 90% of people with glaucoma are unaware they have it until they are officially diagnosed.

2. The condition is usually caused by a build-up of fluid within the eye

Your optic nerve is made up of over a million little nerve fibers, which connect your eye to the brain. If these nerves are put under pressure, it can cause irreversible damage and interfere with the signals responsible for transmitting images. More rarely, poor blood flow (despite normal eye pressure) causes damage to the optic nerve.

If left untreated, glaucoma can lead to permanent vision loss.

3. You could be at risk of glaucoma and not even know it

Several factors can increase your chances of developing glaucoma later in life. These include:

  • Raised pressure within the eye
  • Your age – the older you are, the higher your risk
  • A family history of glaucoma
  • Asian, African or Hispanic heritage
  • Previous eye injury
  • Severe nearsightedness (myopia) or farsightedness (hyperopia)
  • Long-term use of steroid medications
  • Thin corneas (the transparent layer at the front of your eye)
  • Health conditions like diabetes, high blood pressure and migraine

4. There are two main types of glaucoma

Glaucoma can be classified as either open-angle or angle-closure.

Open-Angle glaucoma is the most common form of the condition, where the iris is in the right position, and the uveoscleral drainage canals are clear. But the trabecular meshwork isn’t draining properly.  Hence, the drainage canals become clogged, leading to an increase in eye pressure. Usually, this is a lifelong condition that develops slowly and causes few symptoms in the early stages of the disease.

For Closed-Angle glaucoma, the iris is squeezed against the cornea, blocking the uveoscleral drains and the trabecular meshwork. In some cases, this causes:

  • reduced vision and loss of peripheral vision
  • swollen or bulging cornea
  • pupil dilation to a medium size that doesn’t change with increasing or decreasing light
  • redness in the white of the eye
  • nausea

These symptoms primarily appear in acute cases of closed-angle glaucoma but can also appear in open-angle glaucoma.

Remember, absence of symptoms is not proof that you do not have glaucoma.

5. Approximately 5.1 million people in the world have lost their sight from glaucoma

The number of glaucoma sufferers is rising every year.

While cataract is a more common condition, its effect on vision is often reversible, unlike glaucoma.

That’s why many experts predict that glaucoma may eventually become the most common cause of blindness worldwide.

6. If you catch glaucoma early, the prognosis is usually much better

If glaucoma is diagnosed too late, the vision of the patient will be permanently impaired.

However, if your glaucoma is mild or moderate, your doctor is far more likely to be able to prescribe an appropriate treatment to control eye pressure through medication or surgery, thus preserving your current state of vision.

Treatment options may include:

  • Eye drops
  • Laser eye surgery
  • Glaucoma surgery (trabeculectomy and tube drainage surgery)
  • Minimally invasive glaucoma surgery (MIGS)

In a traditional trabeculectomy, your doctor will create a new channel to drain fluid from your eye. While it will not help to restore your sight, this can help to lower the eye pressure and slow down the rate of vision loss in the future.

MIGS is a fairly recent innovation that may be suitable for you if you have mild to moderate glaucoma, and a low tolerance for glaucoma medications. With MIGS, you’ll benefit from a faster recovery time and a lower risk of complications.

7. You can prevent glaucoma

The first step is to always go for regular eye screening. If your eye doctor detects a problem, they may be able to prescribe you pressure-lowering eye drops, which will help to keep glaucoma at bay.

If you’re concerned about your risk for glaucoma, or if you’re experiencing unusual symptoms, make an appointment with our specialist today.


Glaucoma in Singapore: Stats, Risk Factors and Prevention. (n.d.). Retrieved 3 July 2018 from