An eye occlusion is a blockage in one of the arteries or veins supplying blood to the retina and/or optic nerve. These blockages can cause severe and sudden vision loss. Contact your eye care professional immediately if you experience sudden vision loss, and follow up right away with your family doctor.

Uveitis refers to the inflammation of the eye's middle layer, which consists of the iris, ciliary body, and choroid. Several fungal, viral, or bacterial infections lead to uveitis, as do certain autoimmune (systemic) and inflammatory conditions. In most cases of uveitis, however, the exact cause is unknown. Types