Glaucoma

What is Glaucoma?

Glaucoma is an eye disease that adversely affects the optic nerve. If left untreated glaucoma leads to progressive vision loss and ultimately blindness. It is most common in older people, though it may occur at any age.

What are the Causes of Glaucoma?

Glaucoma is caused by damage to the optic nerve due to abnormally high intraocular pressure in your eye. The optic nerve supplies visual information from your eyes to your brain.

The intraocular pressure increases due to the accumulation of aqueous humour- the fluid that flows throughout the inside of your eye. When this fluid does not properly drain out from your eyes, it builds up and exerts pressure on the optic nerve, leading to nerve damage and vision problems.

What are the Types of Glaucoma?

The different types of glaucoma include the following:

Open-angle Glaucoma: This type is the most common form of glaucoma where the aqueous humour doesn’t circulate freely due to partial blockage in the trabecular meshwork present in the eye. The trabecular meshwork is the tissue through which the aqueous humour drains from the eye.

Closed-angle Glaucoma also called Angle-closure Glaucoma: With this type of glaucoma, a bulge develops in the iris leading to a blockage in the drainage angle between the cornea and iris. This hinders the free-flow of aqueous humour within the eye causing increased pressure.

Normal-tension Glaucoma: This type of glaucoma develops due to damage to the optic nerve despite normal eye pressure. It may be caused due to diminished blood supply to the eye or from an overly sensitive optic nerve.

Pigmentary Glaucoma: This type is caused due to the development of abnormal pigments in the iris which leads to blockage in the free flow of fluid in the eye causing pressure to build up.

Glaucoma in Children: Some children may develop glaucoma at birth or during the first few years of life due to an underlying medical condition or blockage in the flow of the aqueous fluid.

What are the Signs and Symptoms of Glaucoma?

The signs and symptoms of glaucoma depend upon its type and cause.

For open-angle glaucoma, the common signs include:

Patches of blind spots in your central or peripheral vision
Tunnel vision in the later stages

For angle-closure glaucoma, common signs include:

Eye pain
Severe headache
Blurred vision
Redness in the eye
Halos around lights
Nausea and vomiting

How is Glaucoma Diagnosed?

Glaucoma can be diagnosed with a thorough eye examination. You may also undergo any of the following tests:

Dilated eye examination and imaging tests to assess for optic nerve damage
Visual field test to check for areas of vision loss
Tonometry to measure the intraocular pressure
Gonioscopy to inspect the drainage angle between the cornea and iris in the front of your eye
Pachymetry to measure the corneal thickness

How is Glaucoma Treated?

Glaucoma is treated by lowering the intraocular pressure. The choice of treatment depends upon the intensity of your symptoms. The various treatment options include:

Eyedrops
Oral medicines
Laser therapy
Surgery such as minimally invasive glaucoma surgery (MIGS) and trabeculectomy
Insertion of a drainage tube in your eye to help drain away excess fluid
Laser peripheral iridotomy: This procedure is performed to treat acute angle-closure glaucoma. It involves the creation of a tiny opening in your iris using a laser to allow the free flow of aqueous humour.