Many diseases cause transient or permanent visual loss.
Transient loss (amaurosis fugax) occurs most often as a result of blood
flow problem to the eye and may precede a stroke. Inflammation of the eye
nerve (optic neuritis) is associated with eye pain and causes transient
loss of vision, which if unattended may proceed to permanent loss.
Diabetes and glaucoma (increased intra eye pressure) are other common
causes of disturbed vision.
Eyes look at objects, but the brain sees them. Many
disorders of the brain cause blindness. Either the whole of the visual
field, or more typically part of it, is lost depending on the area of the
brain involved. The brain also controls the eye ball movement which is
essential for identical images in both eyes or else double vision is the
Obviously every visual disturbance, even if it is a
transient one, should be evaluated.