Retinal vascular occlusion

Retinal vascular occulsions are due to blockages in any of the blood vessels in the retina of the eye, resulting in reduced vision.

More specifically, blockage of either retinal arteries or retinal veins leads to retinal vascular occlusion by preventing sufficient blood flow to the retina, which is the "screen" onto which the eye projects the images of the outside world that are transmitted to the brain and perceived as "sight" or "vision".

Such blocked and therefore reduced circulation to the retina may result in:

• retinal bleeding,
• retinal swelling,
• retinal neovascularization (i.e. abnormal formation of new blood vessels),
• partial or total loss of vision, and
• in the most extreme untreated cases only, possibly cell death (i.e. leading to permanent damage).

Initial symptoms may vary and can involve subtle or very obvious changes or distortions in vision. For example, in some cases there may be a sudden yet painless blurring of, or reduction in, vision in the upper- or lower-half of the visual field, in others cases increasing vague haziness and / or a loss of clarity of visual perception. (Note that such general symptoms alone are insufficient to indicate retinal vascular occulsions. As for all medical concerns, professional advice should be sought if and when problems or concerns arise.)

Retinal vascular occulsions fall into one of two types, according to the type of blood vessel(s) involved.

They are:

• Retinal artery occlusions, and
• Retinal vein occlusions.

In some rare cases, both artery and vein occlusions may occur together in the same eye. In such situations, physicians might consider the possibility of underlying causes such as leukemia, trauma, or collagen vascular disorders if the cause of the retinal vascular occulsions is not already fully known and understood.