Glaucoma is a group of eye conditions that damage the optic nerve, the health of which is vital for good vision. This damage is often caused by abnormally high pressure in your eye. Glaucoma is one of the leading causes of blindness for people over the age of 60. It can occur at any age but is more common in older adults.
Types of Glaucoma
There are several types of glaucoma, with the two main categories being open-angle glaucoma and angle-closure glaucoma.
- Open-angle glaucoma: The most common form, where the drainage angle formed by the cornea and iris remains open, but the trabecular meshwork is partially blocked. This causes a gradual increase in eye pressure. Many people don’t realize they have the condition until significant vision loss has occurred because open-angle glaucoma develops slowly and is painless.
- Angle-closure glaucoma: This type occurs when the iris bulges forward to narrow or block the drainage angle formed by the cornea and iris. As a result, fluid can’t circulate through the eye and pressure increases. Angle-closure glaucoma may occur suddenly (acute angle-closure glaucoma) or gradually (chronic angle-closure glaucoma).
Symptoms
Open-angle glaucoma often has no symptoms in its early stages. As the disease progresses, blind spots develop in your peripheral (side) vision. Acute angle-closure glaucoma, however, can present sudden symptoms such as severe eye pain, nausea and vomiting, sudden onset of visual disturbance, blurred vision, and halos around lights.
Causes
The exact cause of glaucoma is unknown. However, it’s believed to be related to a combination of genetic and environmental factors. Increased eye pressure is a significant risk factor for optic nerve damage. Other risk factors include age, family history, certain medical conditions like diabetes, and extreme nearsightedness.
Diagnosis
Glaucoma is diagnosed through a comprehensive eye exam that includes the following:
- Tonometry: This test measures the inner pressure of your eye.
- Ophthalmoscopy: This allows the doctor to examine the shape and color of your optic nerve.
- Perimetry: This visual field test measures all areas of your vision to identify any areas of vision loss.
- Gonioscopy: Used to check whether the angle where the iris meets the cornea is open or closed.
- Pachymetry: This ultrasonic wave test measures the thickness of your cornea, which can influence eye pressure readings.
Treatment
While glaucoma cannot be cured and lost vision cannot be restored, treatment and regular check-ups can slow or prevent vision loss, especially if the disease is detected in its early stages. Treatment options include prescription eye drops, oral medications, laser treatment, or surgery to lower eye pressure. Managing glaucoma is about preventing further damage and maintaining the quality of life through ongoing care and monitoring.
Prevention
Regular eye exams are the best form of prevention against glaucoma. Detecting the condition early allows for treatment that can slow the progression of the disease. People at higher risk, including those over 40, with a family history of glaucoma, or who have health conditions that increase the risk of glaucoma, should have more frequent eye examinations.
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