What Can I Do to Prevent Glaucoma?

Glaucoma is a group of eye conditions that damage the optic nerve, which is essential for vision. This damage is caused by abnormally high pressure in the eye. It can occur at any age but is more common in older adults and is one of the leading causes of blindness in people aged over 60. Glaucoma may not have symptoms until the condition is at an advanced stage. The vision loss due to glaucoma can't be recovered, hence, it's important to have regular eye check-ups for early diagnosis and treatment.

Glaucoma occurs because of optic nerve damage. The nerve gradually deteriorates, causing blind spots to develop in the visual field. The exact cause of this is unknown, but it is believed that the nerve damage usually occurs due to increased pressure in the eye.

Eye pressure increases due to the build-up of internal fluid (aqueous humor) that flows throughout the eyes. The fluid normally drains through a tissue called the trabecular meshwork at the angle where the iris (colored part of the eye) and cornea meet. If there is an overproduction of the fluid or the fluid does not drain properly, the fluid builds up causing increased eye pressure.

The signs and symptoms depend on the type and stage of the condition:

Open-angle glaucoma:

• Patchy blind spots in on the sides (peripheral) or central vision, usually in both eyes
• Tunnel vision occurs in the advanced stages

Acute angle-closure glaucoma:

• Severe headache and eye pain
• Nausea and vomiting
• Blurring of vision
• Halos around lights
• Redness of eyes
• Seeing rainbows around light

The damage caused by glaucoma can't be reversed. Early treatment and regular follow-ups can help slow or prevent vision loss, especially in the early stages. Treatment options include:

Prescription eye drops:

• Prostaglandins: These increase the drainage of the fluid in the eye (aqueous humor), resulting in decreased eye pressure.
• Beta-blockers: These reduce the production of fluid in the eye, resulting in decreased eye pressure.
• Alpha-adrenergic agonists: These reduce the production of eye fluid and increase the drainage of fluid.
• Carbonic anhydrase inhibitors: These reduce the production of fluid in the eye.
• Rho-kinase inhibitor: This suppresses the enzyme and rho kinase responsible for the fluid increase.
• Miotic or cholinergic agents: These increase the drainage of eye fluid.

Oral medications:

• Oral medications, such as carbonic anhydrase inhibitors, may be prescribed.

Surgery and other therapies:

• Laser therapy: Laser trabeculoplasty may be done for open-angle glaucoma. A small laser beam is used to open clogged channels in the trabecular meshwork.
• Trabeculectomy: A part of the trabecular meshwork is removed.
• Drainage tubes: A small tube/shunt is inserted in the eye to drain excess fluid and lower eye pressure.
• Minimally invasive glaucoma surgery (MIGS): This procedure reduces eye pressure, usually requires less postoperative care, and has less risk than trabeculectomy or installing a drainage device. They can be combined with cataract surgery.

Treating acute angle-closure glaucoma:

• This is a medical emergency and usually will require both emergency medical and laser or other surgical procedures. Laser peripheral iridotomy is a procedure in which a small opening is created in the iris using a laser. This results in fluid drainage relieving eye pressure.