Cytomegalovirus: A virus that may be carried in an inactive state for life by healthy individuals. It is a cause of severe pneumonia in people with a suppressed immune system, such as those undergoing bone marrow transplantation or those with leukemia or lymphoma.

Uvea: Layer of the eye beneath the sclera, consisting of the iris, ciliary body and choroid.

Retinal detachment: Separation of the light sensitive layer of the eye from its attachment to the underlying tissues

Cataract: Clouding of the lens of the eye or its capsule.

Subluxation of the lens: Partial displacement of the lens of the eye from its original position.