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眼睛解碼

The Roles of Different Eye Care Professionals

Squint

Glaucoma

What are floaters?

Eye care for children and young adults

兒童護眼常識小冊子

Diabetic retinal diseases

Chalazion

Care of contact lens

Allergic conjunctivitis

親子護眼小冊子

戰勝黃班病小冊子

戰勝青光眼小冊子

青光眼手術

Retinal Detachment

Dry Eye Syndrome

白內障

LASER and laser pointers

Tear Gas and Pepper Spray

Precautions on the use of steroid eyedrops & ointment

Glaucoma

Glaucoma is the disease of the optic nerve, which is usually related to raised intraocular pressure. (figure 1). Patients' field of vision may become constricted (figure 3). Without proper treatment, vision will deteriorate and may lead to complete blindness. Early glaucoma has no obvious symptoms.

Glaucoma is classified into 3 types:

Open angle glaucoma (chronic)
Angle closure glaucoma (acute or chronic)
Glaucoma caused by other diseases

All types of glaucoma may cause permanent eye damage. Therefore, prevention of visual loss by early detection and treatment is crucial.

What is angle closure glaucoma?

Angle closure glaucoma is caused by occlusion of the narrow drainage angle (located between the iris and cornea), leading to an increase in eye pressure. If prolonged, the optic nerve fibres will be damaged. It may either occur without reason or caused by other diseases and may be acute or chronic. Acute angle closure glaucoma most commonly occur amongst middle-aged Chinese females, usually with obvious symptoms including: eye pain, blurring of vision, red eyes, headache, vomiting, etc. The eye pressure will be raised within a short period of time. Patients would usually consult an eye doctor and the doctor will reduce the eye pressure immediately.

Chronic angle closure glaucoma may be caused by acute angle closure glaucoma or occur insidiously. It usually has no symptoms and is detected late.

What is open angle glaucoma?

Open angle glaucoma is another commonly encountered condition. It is caused by blockage of the drainage site although the angle is open, leading to raised eye pressure and subsequent damage of the optic nerve. It may either occur without reason, or be caused by other diseases. It is usually detected late due to lack of symptoms.

What are the risk factors for glaucoma?

Risk factors include systemic diseases such as diabetes, hypertension, migraine or family history of glaucoma. Age, trauma, severe near-sightedness and steroid use may also increase the risk of glaucoma.

How to diagnose glaucoma?

The best way to diagnose glaucoma is to undergo regular eye check-ups. Clinical assessments include optic nerve examination, measurement of eye pressure and visual field examination.

How to treat glaucoma?

There is no cure for glaucoma, but if detected and treated appropriately, further damage to vision may be prevented or delayed. Currently, the most effective way of treating glaucoma is to decrease the eye pressure to an appropriate level by using eye drops, laser, eye surgery or a combination of these.

Eye drops is the most commonly used treated. Patients should use the medications timely and regularly. Commonly used eyedrops:
- Beta-blockers have been used for years, which reduce production of aqueous.
- Prostaglandin analogs are newer agents which increase drainage of aqueous.
- Others
Laser is used when the disease is not being controlled by eye drops alone. There are different types of laser treatments available that can be used in conjunction with eye drops to decrease the eye pressure.
Eye surgery is used when both eye drops and laser fail to control the disease. Surgery can decrease the eye pressure by either increasing aqueous drainage or reducing production.

"Doctor, I'm afraid. Will I become blind? How will glaucoma affect me?"

Although the visual damage by glaucoma is permanent, recent medical advances have led to better control. Don’t loose confidence, if you stay optimistic and comply with your treatment, you will not go blind. If your eye pressure can be controlled, your life will not be affected. You can also read more about glaucoma, discuss and share with relatives and friends. You will find that they are very supportive.

Glaucoma statistics:

Glaucoma is the leading cause of blindness in Hong Kong (23%).
Approximately 1,700,000 people in China are blind from glaucoma.
In Taiwan, approximately 200,000-300,000 people suffer from glaucoma.
According to population studies, 60% of blindness in Singaporean-Chinese are caused by glaucoma
Blinding diseases in Japan include diabetic retinal disease (18%), cataract (16%) and glaucoma (15%).
In Thailand, 3.8% of the population have glaucoma.
In Australia, 300,000 people have glaucoma.
In Hyderabad, India, a population study showed that blinding conditions include cataract (30%), retinal diseases (17%) and glaucoma (12%). In Hyderabad, blindness due to primary open angle glaucoma accounts for 19.5% and blindness caused by primary angle closure glaucoma accounts for 42%.
For every 100,000 of those aged 30 or above, 4.7 people in Finland, 10.4 people in Hong Kong and 15.5 Singaporean-Chinese people have acute primary glaucoma.
Females aged over 70 years have a 3.8 times higher risk of glaucoma. 24% of patients with glaucoma have a history of respiratory infection. 35% of patients with glaucoma have a history of cough mixture intake.
Malaysians and Indians in Singapore have a lower incidence of glaucoma than Singaporean-Chinese (6 vs 6.3 people).

Disclaimer: The content of this article is for reference only and does not serve diagnostic or treatment purposes nor does it serve as any recommendation towards the use of particular eye treatment products.