In angle-closure glaucoma, the fluid at the front of the eye cannot reach the angle and leave the eye because the angle becomes blocked by part of the iris. This results in a sudden increase in pressure and is generally a medical emergency, requiring immediate treatment to improve the flow of fluid. Prompt medical treatment is necessary to prevent blindness. Prompt medical treatment is necessary to prevent blindness. Primary glaucoma cannot be contributed to any known cause or risk factor.
Secondary glaucoma develops as a complication of another medical condition or injury.
In rare cases, secondary glaucoma is a complication following another type of eye surgery. Most people who have glaucoma do not notice any symptoms until they begin to lose some vision. As optic nerve fibers are damaged by glaucoma, small blind spots may begin to develop, usually in the side or peripheral vision. Many people do not notice the blind spots until significant optic nerve damage has already occurred. If the entire nerve is destroyed, blindness results.