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/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 any problems or concerns arise.)
Retinal vascular occulsions fall into one of two types,
according to the type of blood vessel(s) involved.
In some rare cases, both artery and vein occlusions may occur together
(in the same eye).
In such situations, physicians may consider the possibility of underlying
causes such as leukemia, trauma, or collagen vascular disorders if the
cause of the retinal vascular occulsion(s) is not already
fully known and understood.
More about Ophthalmology: This section includes short definitions
of many diseases, disorders, and conditions of the eyes and visual system.
For definitions of other terms in this category, choose from the list
to the left (but note that this is not a complete/exhaustive list).
Other related pages include the diagram
of the eye, and definitions
of parts of the eye, a description
of the human retina, and definitions
of parts of the retina, and the section of short definitions
of clinical and surgical procedures re. eyes and human visual system.
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