Glaucoma is the second leading cause of blindness. It includes a group of diseases with a common sign-optic nerve damage associated with visual field defect.

The most common form of glaucoma, primary open-angle glaucoma, develops gradually, without any alarm symptoms. Most people do not even suspect an eye problem until the vision is significantly impaired. When a damage of the optic nerve initiates, so called "Blind spots" appear in the visual field - most common in its peripheral parts. If glaucoma is not treated, it can lead to blindness in both eyes.

Fortunately, if glaucoma is diagnosed and treated in an early stage, the loss of visual functions can be prevented. Having glaucoma, however, requires regular monitoring and treatment for life.

Clinical signs and symptoms: Primary open-angle glaucoma progresses without or with scarce symptoms until it reaches an advanced stage. Open angle glaucoma affects both eyes, but asymmetrically. Thus, the loss of vision is noticed first in one eye.