Visual snow is a neurological visual phenomenon where you see countless tiny, flickering dots—like “TV static”—across your entire field of view, all the time, ...

Visual neglect—often called hemispatial neglect or simply neglect—is a problem of attention and awareness, not a problem of eyesight itself. A person with ...

Vici syndrome is a very rare genetic condition that starts early in life and affects many organs at the same time. The condition is usually caused when a child ...

Vestibular disease rehabilitation is a therapeutic program that uses specific exercises and education to retrain how your balance system works. Your balance ...

Vertical gaze palsy means a person cannot move both eyes normally up or down on command. The problem is not in the eyeball muscles themselves—it is usually in ...

Vertebrobasilar Insufficiency (VBI) is reduced blood flow to the back of the brain that can cause dizziness, imbalance, double vision, slurred speech, ...

Vernal keratoconjunctivitis is a long-lasting (chronic), allergy-type inflammation of the front surface of the eye and the inner side of the eyelids. It mostly ...

The vasculature of the orbit means all blood vessels that bring blood to and take blood away from the tissues inside the eye socket. This includes the arteries ...

Varicella Zoster Virus (VZV) is the virus that causes chickenpox the first time you catch it and shingles when it wakes up again later in life. After ...

Varicella Zoster Virus (VZV) stromal keratitis is inflammation and injury in the middle layer of the cornea (the clear front window of the eye) caused by the ...

Valsalva retinopathy is a sudden bleed in front of the retina (a preretinal hemorrhage) that happens after an intense, brief strain—like a hard cough, ...

Uveitis–Glaucoma–Hyphema (UGH) syndrome is a problem that can happen after cataract surgery when an artificial lens or another device inside the eye rubs ...

Hyphema means blood inside the front chamber of the eye (the space between the cornea and the iris). The blood comes from tiny torn blood vessels in the iris ...

Uveitis masquerade syndromes are eye problems that look like uveitis (inflammation inside the eye) but are not true autoimmune uveitis. In other words, the eye ...

Uveitic cataract is a cataract (a clouding of the eye’s natural lens) that develops because of uveitis, which is inflammation inside the eye. The eye’s inner ...

Uveitis is inflammation inside the eye, focused on a layer called the uvea. The uvea is the eye’s middle coat and includes the iris (the colored ring that ...

Uveitic glaucoma is high pressure inside the eye that happens in a person who has uveitis (inflammation inside the eye). The uvea is the “middle coat” of the ...

A hypermature cataract is the end stage of a cataract. A cataract means the natural lens inside the eye has turned cloudy. In early stages, only part of the ...

Uveal pseudomelanoma means a spot or mass in the eye that looks like a uveal melanoma (a true eye cancer) but actually isn’t cancer. “Uveal” refers to the ...

Uveal lymphoma is a cancer of lymphocytes (a type of white blood cell) that grows inside the uvea of the eye. The uvea is the middle layer of the eyeball and ...