Secondary Glaucoma

Secondary glaucoma describes a group of glaucomas caused by some other identifiable eye or systemic disease, eye surgery, eye trauma, prolonged use of certain medications, or ocular inflammation. There are many secondary causes of glaucoma.These can be either of the open angle or closed angle variety.

The eye receives its nourishment from a clear fluid that circulates inside the eye.

 
Fluid circulating inside eye

This fluid must be constantly returned to the blood stream through the eye's drainage canal, called the trabecular meshwork. In the case of open-angle glaucoma, something has gone wrong with the drainage canal. When the fluid cannot drain fast enough, pressure inside the eye begins to build.

Excess fluid builds pressure

This excess fluid pressure pushes against the delicate optic nerve that connects the eye to the brain. If the pressure remains too high for too long, irreversible vision loss can occur.

Excess fluid pressure pushes
against the optic nerve
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Diagnosing secondary glaucoma:

Everyone should be checked for glaucoma at around age 35 and again at age 40. Those considered to be at higher risk, including those over the age of 60 should have their pressure checked every year or two and every year after age 65.

Your doctor will use tonometry to check your eye pressure. After applying numbing drops, the tonometer is gently pressed against the eye and its resistance is measured and recorded.	Tonometry is used to check your eye pressure
An ophthalmoscope can be used to examine the shape and color of your optic nerve. The ophthalmoscope magnifies and lights up the inside of the eye. If the optic nerve appears to be cupped or is not a healthy pink color, additional tests will be run.	An ophthalmoscope is used to examine your optic nerve
Perimetry is a test that maps the field of vision. Looking straight ahead into a white, bowl-shaped area, you'll indicate when you're able to detect lights as they are brought into your field of vision. This map allows your doctor to see any pattern of visual changes caused by the early stages of glaucoma.	Perimetry maps your field of vision
Gonioscopy is used to check whether the angle where the iris meets the cornea is open or closed. This helps your doctor determine if they are dealing with open-angle glaucoma or narrow-angle glaucoma.	Goniscopy is used to help your glaucoma type

Treatments for secondary glaucoma:

This type of glaucoma is unlike chronic open angle glaucoma in that when the problem causing raised intraocular pressure is corrected or cured (if this is possible), the pressure may return to normal and further medication may be unnecessary. Unfortunately, existing damage to the visual field will remain.