What is glaucoma?
Glaucoma is the disease of the optic nerve which carries visual signal from retina to the brain. It is usually caused by abnormally high eye pressure, which damage the optic nerve. You can develop glaucoma even without exceeding the normal range of eye pressure, which is 12-22 mmHg. There may be no symptoms of glaucoma until significant vision loss occurs. This is why glaucoma is also termed as “silent thief of vision”. Vision loss due to glaucoma can not be restored. There is no cure of glaucoma as of date. However, it can be prevented. It is important that you should see an eye doctor for early diagnosis.
What is eye pressure? How does it cause glaucoma?
Aqueous humor, the fluid which is produced by ciliary muscles in the eye is drained through the different channels or ducts to the blood stream. With the aging process, these ducts may get clogged, and the fluid builds up in the eye; thus, the pressure increases and damage the optic nerve. This common type of glaucoma is known as open angle glaucoma. This type of glaucoma usually causes gradual decrease in vision.
Another type of glaucoma is narrow-angle glaucoma. Angle, the space between the cornea and the color part of the eye (iris) is wide or narrow. The angle allows the eye fluid (aqueous humor) to pass through the ducts smoothly so that the eye pressure is stable. If those people with narrow-angle are dilated (dilating eye drops), the angle can be blocked, and the fluid can not pass through. This mechanical obstruction of the angle can result in an acute attack of narrow-angle glaucoma.
Eye injury can also cause glaucoma. Eye injury may block the drainage system of the fluid, which can increase eye pressure and cause damage to the optic nerve.
Having high pressure does not necessarily mean you have glaucoma. Sometimes you may have high eye pressure but there is no damage to the optic nerve. The Optic nerve may also look like glaucoma. This condition is known as ocular hypertension. When you have these signs, your doctor monitors you as a “glaucoma suspect“.
Glaucoma can be acquired at birth. Childhood or congenital glaucoma usually appears between birth and 3 years of age. If you see your child has a watery eye, light sensitivity, cloudy cornea, you should see an Ophthalmologist as soon as possible, for it may be glaucoma.
How is glaucoma diagnosed?
You should see an eye doctor to nab glaucoma at the early stage. Your doctor will dilate your eyes to check the optic nerve and retina. You will also have non-invasive diagnostic tests such as visual field, Optical Coherence Tomography (OCT), Pachymetry (measuring the thickness of cornea), Gonioscopy ( to evaluate the angle), Tonometry (eye pressure measurement). After reviewing all the diagnostic tests and clinical examination, your doctor will tell you if you have glaucoma.
Am I at risk of developing glaucoma?
You are at risk of developing glaucoma if;
- Over 60
- African American
- Family history of glaucoma
- Using steroid
- Eye injury
How is glaucoma treated?
Although there is no cure for glaucoma, it can be prevented. There are different treatment modalities to control eye pressure. You may need eye drops. People respond differently to the eye drops so your doctor will recommend you the best eye drops for your eyes. If you have an open-angle glaucoma, your eye doctor may recommend laser surgery to open the ducts of the drainage system. If you have a narrow-angle glaucoma, you might need laser to create an alternative pathway for the fluid to pass through. The goal of performing laser is to lower your eye pressure. Additionally, you may also need surgery, and your eye doctor will determine if it is indicated.
How do I know if I have glaucoma?
Open angle glaucoma usually has no symptoms. Diagnosing glaucoma at a very early stage is important to prevent loss of vision. However, as glaucoma progresses, you may experience headache, eye pain, blurred near vision, halos around light, and tunnel vision. In glaucoma, you start loosing your peripheral vision that progresses towards your central vision.
If there is an acute attack of narrow-angle glaucoma, you may experience severe pain, redness, and headache. Your vision may also drop significantly within a few hours. If you experience these symptoms, you should see an ophthalmologist immediately.