Uveal Effusion Syndrome (UES) is a rare eye condition where fluid collects in the potential space around the uveal tissues—the choroid, the ciliary body, and ...

Usher syndrome is a genetic condition that a person is born with. It mainly affects hearing, vision, and sometimes the balance system of the inner ear. In ...

Neurodegenerative diseases are long-lasting conditions where nerve cells (neurons) in the brain and spinal cord are damaged or die earlier than they should. ...

Urrets-Zavalia syndrome is a rare complication after eye surgery where the black center of the eye (the pupil) becomes stuck in a large, round, and ...

Upper eyelid retraction means the upper lid sits too high on the eye. In normal, relaxed gaze, the upper lid usually covers the top 1–2 millimeters of the ...

Upper eyelid blepharopathy means “a disease or dysfunction of the upper eyelid,” most often showing up as eyelid margin inflammation (blepharitis), meibomian ...

Bilateral pigmentary retinopathy means that both eyes show abnormal pigment changes in the retina, the light-sensitive layer at the back of the eye. The ...

Unilateral Pigmentary Retinopathy (UPR) describes a retina-degenerating condition in one eye that looks and behaves like retinitis pigmentosa (RP), but with ...

Bilateral coronal synostosis means both coronal sutures—the flexible seams running from ear to ear across the top of a baby’s skull—fuse too early. In a ...

Unilateral coronal synostosis means one of the baby’s two coronal sutures (the joints that run from ear to ear across the top of the skull, just behind the ...

Sudden visual loss means your eyesight drops quickly over minutes, hours, or a few days. You may notice a dark curtain, a gray shadow, foggy or blurred vision, ...

Ultramarathon-induced corneal edema is a temporary swelling of the clear front window of the eye (the cornea) that happens during or soon after very long, hard ...

TINU syndrome is a rare inflammatory disease that affects both the kidneys (specifically the tiny tubes and the tissue around them—this part is called ...

Tubulointerstitial Uveitis is known as tubulointerstitial nephritis and uveitis (TINU) syndrome—a disorder where the kidneys’ tubules/interstitium are inflamed ...

Tubulointerstitial nephritis (TIN) is inflammation and injury that mainly affect the tubules (the tiny pipes that balance water, salt, acid–base, and waste) ...

Tuberculosis uveitis (often called ocular TB) is inflammation inside the eye that happens when your immune system reacts to germs from Mycobacterium ...

Trochleitis means inflammation around the trochlea, the tiny pulley of cartilage at the inner-upper corner of the eye socket where the superior oblique tendon ...

Trisomy 21, commonly called Down syndrome, is a genetic condition where a person has three copies of chromosome 21 in their cells instead of the usual two. ...

Trisomy 13—also called Patau syndrome—is a genetic condition in which a person has three copies of chromosome 13 in their cells instead of the usual two. ...

Trigeminal trophic syndrome is a rare skin and nerve disorder that appears after damage to the trigeminal nerve (the 5th cranial nerve that carries feeling ...