What is glaucoma?
Known as the“silent thief of sight”, Glaucoma slowly damages the eyes and can cause irreparable harm before there is any vision loss detected. Early detection and treatment are the most important steps to prevent vision loss. Glaucoma is a group of eye diseases that damage the optic nerve, a cable at the back of the each eye that connects it to the brain. It often affects both eyes, usually to varying degrees. As most cases won’t have any symptoms, one of the best ways to detect glaucoma is during a routine eye test – that’s why it’s so important to have one regularly.
What causes glaucoma?
An abnormality in the eye’s drainage system can cause fluid to build up, leading to excessive pressure that causes damage to the optic nerve. The optic nerve is a bundle of nerve fibers that connects the retina with the brain. This damage leads to loss of eyesight.
Glaucoma typically develops when this increased pressure damages the optic nerve, which connects the eye to the brain, and harms the nerve fibres from the retina, the light-sensitive nerve tissue that lines the back of the eye.
In acute glaucoma cases this pressure rises rapidly to higher levels, even causing pain.
Glaucoma typically develops when this increased pressure damages the optic nerve, which connects the eye to the brain, and harms the nerve fibres from the retina, the light-sensitive nerve tissue that lines the back of the eye.
In acute glaucoma cases this pressure rises rapidly to higher levels, even causing pain.
Types of glaucoma
The vision loss starts out in the edges of the visual field and slowly impacts the central vision. It takes months to years after the nerve damage has occurred before youmay notice the symptoms. Once vision is lost, it cannot be recovered.
There are various types of glaucoma:
Open-angle glaucoma
The most common form of glaucoma, this type is caused by damage to the filter in the eye’s drainage canals.
Angle-closure glaucoma
This type of glaucoma is caused by a rapid blockage of the eye’s drainage canals due to a closed or narrow angle between the iris and cornea where the filter is located.
Low-tension or normal-tension glaucoma
A type of glaucoma in which damage occurs to the optic nerve without eye pressure exceeding its normal range.
Congenital glaucoma
A type of glaucoma that occurs in infants when there are incorrect or underdeveloped drainage canals in the eye during the prenatal period.
Uveitic (inflammatory) glaucoma
This type of glaucoma caused by autoimmune and inflammatory disorders.
Neovascular glaucoma
A type of glaucoma associated with poorly controlled diabetes and other conditions that damage the blood vessels in the body.
Glaucoma Causes
Many factors lead to glaucoma. While increased eye pressure is the only known modifiable risk factor known at this time, is it not a cause. Glaucoma can also develop with normal eye pressure.
There are various types of glaucoma:
Open-angle glaucoma
The most common form of glaucoma, this type is caused by damage to the filter in the eye’s drainage canals.
Angle-closure glaucoma
This type of glaucoma is caused by a rapid blockage of the eye’s drainage canals due to a closed or narrow angle between the iris and cornea where the filter is located.
Low-tension or normal-tension glaucoma
A type of glaucoma in which damage occurs to the optic nerve without eye pressure exceeding its normal range.
Congenital glaucoma
A type of glaucoma that occurs in infants when there are incorrect or underdeveloped drainage canals in the eye during the prenatal period.
Uveitic (inflammatory) glaucoma
This type of glaucoma caused by autoimmune and inflammatory disorders.
Neovascular glaucoma
A type of glaucoma associated with poorly controlled diabetes and other conditions that damage the blood vessels in the body.
Glaucoma Causes
Many factors lead to glaucoma. While increased eye pressure is the only known modifiable risk factor known at this time, is it not a cause. Glaucoma can also develop with normal eye pressure.
Risk factors of glaucoma
Glaucoma can affect anyone, but certain factors can increase an individual's risk of developing the condition. Some of the key risk factors for glaucoma include:
- Your risk of developing glaucoma is four times higher if you have a close blood relative who has it.
- Age plays a big part. Chronic glaucoma affects up to two in every 100 people over the age of 40 and around five in every 100 people over 80.
- Consistently raised pressure in the eye, called ocular hypertension (OHT), is a risk factor.
- People with diabetes may be at higher risk of developing glaucoma.
- Very high blood pressure can lead to an increase in intra ocular pressure, which can increase your risk of developing glaucoma.
- Low blood pressure can lead to insufficient blood supply to the optic nerve, which can also cause problems.
- Eye conditions, surgeries or injuries: injury to the eye can cause secondary open-angle glaucoma, either immediately after the injury or some years later.
Glaucoma symptoms
Most people with glaucoma do not notice symptoms until they begin to lose eyesight. As glaucoma damages optic nerve fibers, small blind spots may begin to develop. These spots usually occur on the side or in the peripheral vision. Many people do not notice the blind spots until significant optic nerve damage has already happened.Blindness can result when the entire nerve is destroyed.
Symptoms of Acute-Closure Glaucoma
One type of angle-closure glaucoma, called acute angle-closure glaucoma, does produce noticeable symptoms. This is because there is a quick buildup of pressure in the eye. Each person may experience symptoms differently, which include:
Symptoms of Acute-Closure Glaucoma
One type of angle-closure glaucoma, called acute angle-closure glaucoma, does produce noticeable symptoms. This is because there is a quick buildup of pressure in the eye. Each person may experience symptoms differently, which include:
- Blurred or narrowed field of vision
- Seeing halos or “rainbows” around lights
- Vomiting
- Severe pain in the eyes
- Nausea
- Headache
