Peripheral (side) vision loss means the edges of what you can see shrink or disappear. You may still see clearly straight ahead, but you miss what happens to ...

Central vision is the sharp, detailed sight you use to read, recognize faces, thread a needle, or see the small details in a picture. It lives in a tiny area ...

Lymphocytic choriomeningitis (often shortened to LCM) is an infection caused by the lymphocytic choriomeningitis virus (LCMV). This virus belongs to a family ...

Lyme disease is a bacterial infection you get from the bite of an infected black‑legged tick. The tick feeds on a small animal (often mice) that carries ...

Lower eyelid retraction means the lower eyelid sits too low on the eye. Instead of gently touching the lower edge of the colored part (the iris), the lid is ...

Lower eyelid blepharoplasty is a surgery that improves the look and shape of the lower eyelids. In plain words, it is a carefully planned procedure to treat ...

Lowe syndrome is a rare, inherited condition that mainly affects the eyes, the brain/nerves, and the kidneys—which is why doctors also call it ...

Low vision means your sight is permanently reduced in a way that regular glasses, contact lenses, medicine, or surgery cannot fully fix. People with low vision ...

Long Anterior Zonules (LAZ) means some of the tiny “guy-wire” fibers that hold your lens—the zonules—reach farther onto the front surface of the lens (called ...

African eye worm is the common name for Loa loa, a tiny thread-like parasite (a filarial worm) that lives and moves in the soft tissues under the skin and ...

Loa loa filariasis, also called loiasis (pronounced low-ah EYE-uh-sis), is a parasitic infection (an illness caused by a tiny living thing) due to Loa loa, a ...

Lisch corneal dystrophy is a genetic eye condition that affects the skin-like surface layer of the clear window of the eye (the corneal epithelium). Tiny ...

Lipid keratopathy means fat (lipid) gets deposited inside the clear front window of the eye, called the cornea. The cornea is normally crystal-clear and has no ...

Lipemia retinalis is a look that eye doctors see at the back of the eye when the fat in the blood (especially triglycerides carried in “chylomicrons”) is ...

Linear interstitial keratitis is a very rare form of corneal inflammation in which a line-shaped streak appears inside the stroma (the middle, transparent ...

Your cornea (the clear “window” at the front of the eye) is covered by a very thin skin called the corneal epithelium. That skin constantly wears out and must ...

Ligneous conjunctivitis is a rare kind of long-lasting, often-returning “pink eye” where thick, wood-like (“ligneous”) layers—called pseudomembranes—build up ...

Light–near dissociation means the pupil doesn’t shrink to light, but does shrink when you look at something near. It’s a sign, not a disease. Think of it as a ...

Linear interstitial keratitis (LIK) is a non-ulcerative, line-shaped inflammatory streak inside the cornea’s stromal layer. It looks like a straight, pale or ...

Your cornea is the clear “window” at the front of the eye. Its skin-like surface (called the corneal epithelium) is constantly renewed by special repair cells ...