Glaucoma is a group of eye related disorders that cause damage to the optic nerve that carries information from the eye to the brain. The optic nerve is a bundle of millions of individual nerve fibers that transmits the visual signals from the eye to the brain.
Increase in eye pressure may cause progressive damage to the optic nerve and loss of nerve fibers.
In most cases, glaucoma is associated with higher-than-normal pressure inside the eye — a condition called ocular hypertension. But it can also occur when intraocular pressure (IOP) is normal.
If untreated or uncontrolled, glaucoma first causes peripheral vision loss and eventually can lead to blindness.
Risk factors:
- Age >40 years
- Family history of glaucoma
- Far sightedness
- Hypertension
- Sleep apnoea
- Chronic eye inflammation
- Thinner corneas
- Medications which increase eye pressure – steroids
- Eye injuries
- Congenital glaucoma
Types:
Primary open angle glaucoma
- This is the most common form of glaucoma. Damage to the optic nerve is slow and painless. Those affected can lose a large portion of vision before they notice any vision problems.
- One theory about its development is that the eye’s drainage system becomes inefficient over time. This leads to an increased amount of fluid and a gradual buildup of pressure within the eye.
Angle closure glaucoma
- This is a less common type of glaucoma , however, a medical emergency.
- It can cause drop in vision over days if ignored
- It occurs when the drainage angle in the eye (formed by the cornea and the iris) closes or becomes blocked. Many people who develop this type of glaucoma have a very narrow drainage angle.
- With age, as this angle narrows, the fluid in the eye is blocked from the drainage system. Therefore the fluid builds up and eye pressure increases
Secondary glaucoma
This type of glaucoma results from an injury or another eye disease. It may be caused by a variety of medical conditions, medications, physical injuries, and eye abnormalities. Infrequently, eye surgery can lead to secondary glaucoma.
Normal-tension or low-tension glaucoma
In this form of glaucoma, eye pressure remains within the “normal” range, but the optic nerve is damaged nevertheless. It is not known why this happens. Possibly, people with low-tension glaucoma have an abnormally sensitive optic nerve. Or they may have a reduced blood supply to the optic nerve
Symptoms
The signs or symptoms of glaucoma can vary depending on the type. Primary open-angle glaucoma often develops slowly and painlessly, with no early warning signs. It can gradually destroy one’s vision without even knowing it. The first indication that a person has glaucoma may occur after some vision has been lost.
Acute angle-closure glaucoma results from a sudden blockage of drainage channels in the eye, causing a rapid buildup of pressure. In this form of the disease, a patient would have blurred vision, the appearance of halos or colored rings around lights, and pain and redness in the eye.
Diagnosis
Glaucoma is diagnosed through a comprehensive eye examination. Because glaucoma is a progressive disease, meaning it worsens over time, an early screening can help in diagnosis. Patients should have routine comprehensive exams to monitor any changes.
Treatment
Glaucoma treatment is aimed at reducing pressure in the eye. Regular use of prescription eye drops are the most common and often the first treatment. Some cases may require systemic medications, laser treatment for glaucoma, or surgery. While there is not yet a cure for glaucoma, early diagnosis and continuing treatment can preserve eyesight.
