Glaucoma is the second leading cause of blindness in the world and the leading cause of irreversible blindness. It is a result of an increase in the pressure of the eye (intraocular pressure) which causes progressive damage to the optic nerve. The optic nerve is responsible for carrying visual impulses to the brain and its damage results in loss of vision. In most cases, the condition progresses slowly and insidiously, and the patient is not often aware of the condition until a late stage. By the time one notices a deterioration of vision, there is often already moderate to severe damage to the nerve. This is why this disease has been called the “silent thief of sight”.
Different Types of Glaucoma
Most glaucomas present as a slowly progressive disease, with the common forms being Primary Open-Angle Glaucoma and Chronic Angle-Closure Glaucoma. These usually affect middle-aged or elderly people. Glaucoma may be inherited, which means that relatives of people with glaucoma have a higher risk.
Primary Open-Angle Glaucoma
This is the commonest type of glaucoma in most countries. The glaucoma progresses slowly and in the initial stage has no obvious symptoms.
Chronic Angle-Closure Glaucoma
Angle-closure glaucoma occurs commonly among Asians. Singapore has the highest reported incidence of angle-closure glaucoma in the world. In the chronic form, similar to Primary Open-Angle Glaucoma, this type of glaucoma progresses gradually, and often goes unnoticed for a long time. It results from progressive blockage of the drainage channels of the eyeball, resulting in a prolonged rise in eye pressure.
Acute Angle Closure Glaucoma
This type of glaucoma usually affects women in the middle or elderly ages. It develops because of a blockage of the fluid drainage pathway located in the angle of the eye, resulting in a rapid rise in the fluid pressure within the eye. The symptoms are sudden and dramatic requiring patients to seek medical attention urgently.
Glaucoma may arise when there is inflammation of the eyeball or when a cataract becomes too advanced and swollen. Other causes are eye surgery and injury to the eye.
Symptoms of Glaucoma
Those with Primary Open-Angle Glaucoma and Chronic Angle-Closure Glaucoma often do not have any symptoms in the early stage, because the peripheral vision is affected first and the disease is slowly progressive. Most people do not realise they have glaucoma until it is more severe when the central vision starts being affected. By which time, there may already be significant irreversible nerve damage.
Acute angle-closure glaucoma presents with sudden severe eye pain, redness, blurring of vision and haloes around lights. This is an eye emergency where medical consultation must be sought immediately.
Be aware of the following risk factors of glaucoma:
- Over the age of 60
- A history of glaucoma in your family
- Diagnosed with diabetes and high blood pressure
- Have an abnormally high or low degree of short- or long-sightedness
- Have had an eye injury or certain types of eye surgery
To reduce the risks of developing chronic glaucoma, pay careful attention to your eye health and undergo regular comprehensive eye exams as advised by your eye doctor.
Determine the Best Possible Treatment With Early Glaucoma Screening
Glaucoma progresses slowly and insidiously. Most people only have minimal symptoms during the early phase of the disease. They are only aware of the condition during the late stages. Glaucoma eye screening is very useful in picking up the disease early so that the best possible treatment may be started.