The most common form of glaucoma is open angle glaucoma. This is a progressive disease of the optic nerve caused by elevated pressure inside the eye. Vision that is lost from glaucoma can never be restored.

With glaucoma, because the trabecular meshwork (eye’s drainage filter) is clogged (1), the fluid present inside the eye, called aqueous humor, doesn’t drain well. As it builds up, it raises the pressure inside the eye (2). The high pressure damages the optic nerve by killing the nerve fibers that run into it (3) leading to the excavation of the optic nerve head.

As the pressure rises, the depth and width of the excavation increase, causing gradual loss of visual field. The side visual field is often affected first. Over time, the central visual field is also lost, leading to blindness.

Tests for glaucoma

Automatic Tonometry
This is a test to measure the intraocular pressure without making any contact with the eye.

OCT scan
With the OCT scanner, your doctor can perform multiple analyses for glaucoma including:

• Retinal Nerve Fiber Layer (RNFL) Analysis reveals the thickness of the layer of the retina that contains nerve fibers traveling up to the optic nerve. If glaucoma is present, this layer may gradually lose thickness.
• Optic Nerve Head Analysis reveals the structure of the optic nerve where it originates in the retina. With glaucoma, the excavation in the optic nerve head may gradually enlarge.

Revealing the complete picture

The OCT Scan
Without making any contact with the eye, the Stratus OCT scanner takes multiple pictures across the retina to show your doctor its internal structure.

This unique view is called cross-sectional images of the retina because it enables your doctor to look directly at a “cutaway” view of the layers of the retina and optic nerve head to evaluate their characteristics. Early detection is crucial in initiating or modifying the treatment of glaucoma and retinal problems before permanent damage occurs.

Testing your visual field

Your visual field is the total area you can see. During a visual field test, you press a button each time you see a light. A printout shows the size of the area you can see. Dark areas in your printout show reduced vision. As nerve damage increases, more dark areas appear.

The test is designed to verify the central and peripheral fields of vision. It should be repeated regularly and the results analyzed and compared to previous ones.

The glaucoma progression analyzer
This latest breakthrough in visual field combines the enhanced capability to detect glaucoma early with tools to monitor closely its progression.

Pachymetry
It was recently discovered that corneal thickness plays an important role in glaucoma. The Orbscan II scans thousands of points on the surface of the cornea to measure its thickness.

Digital photography
The advanced Topcon DC-1 Digital Camera is used to periodically take a series of digital photos of your eye and your optic nerve head. The images are transmitted instantly to computerized imaging software so that they can be analyzed and compared over time.

This technology allows your doctor to detect changes that might not be noticed during a regular ophthalmic exam. Your doctor can actually show you detailed images of your eye and your optic nerve on the computer screen, while explaining how the glaucoma is progressing in your case.

Did you know that?
Your risk of developing glaucoma is higher if you are over 50 years old, if you have myopia, diabetes, or if there is a history of glaucoma in your family.