WHAT IS GLAUCOMA?
Glaucoma is caused by fluid building up inside the eye, thus raising the eye pressure. An increase in eye pressure would exert pressure on the optic nerve. Since the eye is a fairly rigid shell, the pressure in the eye is forced to escape from an exit at the back of the eye. This pressure on the optic nerve causes nerve damage. The optic nerve is responsible for sending signals from the eye to the brain, which gives us vision to see objects clearly.
Our eye constantly makes a fluid called the ‘aqueous humor’. This fluid flows into the eye and drains out constantly in an equal matter, achieving equilibrium. However, if the drainage angle is not working properly, the fluid builds up, and intraocular eye pressure increases. This uncontrolled increase in eye pressure causes optic nerve damage. The optic nerve is made up of more than a million tiny nerve fibers. This is like an electric cable with many small wires. An increase in eye pressure subsequently results in these nerve fibers dying, which then causes glaucomatous visual field defects.
Unfortunately, most of the time, you do not know if you have glaucoma without seeing an eye doctor. The most common type of glaucoma is open-angle glaucoma. However, there are NO warning signs and NO obvious symptoms during the early stages of glaucoma. As the disease progresses, blind spots and visual field defects slowly develop at the peripheral side of vision. Most people with open-angle glaucoma do not notice any change in their vision until it is too late, and the damage is quite severe.
This is why Glaucoma is known as THE SILENT THIEF OF SIGHT!! People who have severe vision damage from glaucoma may be able to see objects right in front of them and nothing at the side, like looking through a tunnel. Over time, if left untreated, it may progress to blindness.
HOW GLAUCOMA CAN BE TREATED?
Glaucoma damage is permanent and cannot be reversed. Although we cannot cure glaucoma completely, ophthalmologists can halt the disease and slow disease progression with eye drops, laser glaucoma therapy, and glaucoma eye surgeries. The goal of these treatments is to lower the eye pressure by either suppressing fluid production in the eye or increasing drainage of fluid out of the eye.
WHAT SHOULD WE DO?
Early eye screening is very important. Everyone should have a baseline eye examination with an ophthalmologist to screen for glaucoma and other eye diseases. Very often people do annual blood medical checks and dental checks but often overlook the importance of eye check-ups. In fact, those who have a family history of glaucoma eye disease are at higher risk and should see their ophthalmologist for an annual eye check-up at least once per year. With regular check-ups, we can catch the disease at its early stage and prevent visual loss.
WHAT TO EXPECT AT THE EYE CLINIC?
When seeing an eye specialist, the doctor will first take a history and identify any risk factors of glaucoma. This is followed by a series of eye examinations:
- Slit lamp examination.
- Goldman Tonometry – Intraocular eye pressure check to check the pressure in the eye.
- Gonioscopy – To evaluate the drainage angle of the eye using a contact lens.
- Dilated eye exam – To view and examine the optic nerve.
- Optical Coherent Tomography Eye Scan (OCT) – A non-invasive imaging eye scan that measures the severity of the loss of optic nerve fiber to look for structural damage.
- Visual field test – measures the functional damage of the optic nerve by mapping out the peripheral vision function, looking for any glaucomatous visual field damage like black spots or grey spots. The machine will show blinking lights. The patient will determine whether the blinking light is visible or not.
WHAT ARE THE TIPS TO PREVENT GLAUCOMA?
- Early detection and early treatment.
Glaucoma usually has no symptoms at its early stages. Those who have a family history of glaucoma eye disease are at higher risk and should see their ophthalmologist for a baseline check-up followed by an annual eye check-up at least once per year. With regular check-ups, we can catch the disease at its early stage and prevent visual loss. - Check your Medications!
People who are on long-term steroid use should always have regular eye checks and follow-ups with their eye doctor to prevent glaucoma. Steroids for a long period of time can increase the eye pressure. Increased eye pressure can cause glaucoma. It is important to check your eye pressure and optic nerve with your eye doctor, especially if you are on long-term steroid medication. Steroids can come in many forms including pills, injections, creams, steroid patches, steroid nasal sprays, and steroid inhalers. Traditional medication, plant roots, and herbs may also contain unknown amounts of steroids. Apart from glaucoma, steroids can also cause cataracts. Physicians and Dermatologists who have patients on long-term steroids often refer their patients to the ophthalmologist for eye checks. - Exercise helps, but only the right exercise!
Exercise can lower blood pressure and eye pressure, but the right exercise is needed. Cardiovascular exercises are good to encourage good blood circulation. However, prolonged straining, breath-holding, and positioning the head below the level of the heart are not advised as they cause a transient increase in eye pressure. This may be harmful to those who already have glaucoma. Before you exercise, speak to your eye doctor first for advice. - NO head-down position!
Avoid the head-down position for a prolonged period, like in yoga (Headstand and Handstand). An excessive amount of fluid buildup in the eye can worsen the damage for people who already have glaucoma. - NO tight neckties!
A tight necktie can increase eye pressure. The British Journal of Ophthalmology published a paper that found that wearing a tight necktie is significantly correlated to a higher incidence of glaucoma. Increased pressure around the neck will obstruct blood circulation from the head to the heart, thus increasing fluid in the eye and potentially increasing intraocular eye pressure. So, remember to loosen the tie! - Sleeping habits – Do not sleep face down.
If you have glaucoma, do not sleep in a prone position, whether face down, eyes on arms, or eyes on the pillow. This prone position would potentially obstruct fluid drainage in the eye and increase intraocular pressure. - Sleeping habits – Do you snore?
If you or your friend or family snore loudly during sleep, it may be obstructive sleep apnea (OSA). OSA patients have repeated episodes of pause and shallow breathing during sleep. They have a 10 times higher risk of glaucoma! Therefore, it is important to get tested for obstructive sleep apnea and get treatment. - Avoid eye injury.
Angle recession glaucoma can happen after a trauma to the eye. Remember to wear protective eyewear during sports or when working with heavy instruments. It is good to have protective sunglasses when out in the sun. An article in JAMA (Journal of the American Medical Association) found that sunlight increases the risk of exfoliation of glaucoma. - Blood pressure too low can be bad for glaucoma.
Keep track of blood pressure as nocturnal blood pressure dips can reduce blood supply to the eye. - Protective vitamins – A, C, E, B12.
B12 is good for maintaining the health of the optic nerve. Apart from that, studies showed that patients taking regular vitamins A, C, and E are less likely to have glaucoma.
For expert care, visit the DR JOCELYN WU EYE CENTRE to book your consultation.
