Choroidal metastases are cancer cells that have travelled through the bloodstream from another part of the body and seeded in the choroid—the spongy, ...
Choroidal folds are alternating grooves and ridges that form in the innermost coats of the back of the eye—the choroid, Bruch’s membrane, and retinal pigment ...
Choroidal melanoma grows from pigment‑making (melanocyte) cells in the choroid—the carpet‑like sheet of blood vessels that feeds the retina at the back of the ...
Chorioretinitis sclopetaria is a rare, trauma‑driven eye disease in which a shock wave from a high‑velocity object that passes close to the globe—but does not ...
Chiasmitis—also called chiasmal optic neuritis or optic‑chiasm inflammation—is a rare, sight‑threatening disorder in which the immune system, an infectious ...
Cherubism is a rare genetic bone condition that causes the lower face—especially the jaws and cheeks—to look round, full, and “angelic,” like the cherubs in ...
A cherry‑red spot is a distinctive, bright‑red circle seen in the very center of the retina (the fovea) when an eye‑care professional looks inside your eye ...
An eyelid chemical peel (sometimes called a periorbital chemical peel or chemexfoliation of the lids) is a controlled application of a caustic solution—most ...
A chemical injury of the conjunctiva—also called an ocular chemical burn—happens when a liquid, powder, or gas that is strongly alkaline (high‑pH) or acidic ...
Cheiro‑Oral Syndrome is a very specific kind of sensory stroke. In COS a tiny lesion—most often an ischemic “lacunar” infarct or a small bleed—damages the ...
Charles Bonnet Syndrome is a “phantom‑vision” condition in which a person who has already lost part of their sight suddenly starts seeing things that are not ...
CHARGE syndrome is a rare, life‑long birth condition that affects many different organs at once. The word “CHARGE” began as an easy memory aid for ...
Chalcosis (often called chalcosis bulbi) is a slow‑moving eye disorder that happens when a small piece of copper or a copper‑based alloy is left inside the ...
A chalazion (pronounced kuh‑LAY‑zee‑on) is a small, localized swelling inside the upper or lower eyelid that forms when thickened oil can’t escape from a ...
Cerulean cataract—sometimes called “blue-dot cataract” because of the tiny sky-blue speckles it scatters through the lens—is a rare, usually inherited form of ...
Cerebrotendinous xanthomatosis, usually shortened to CTX, is a very rare, inherited (autosomal‑recessive) metabolic disease in which the body cannot finish one ...
Cerebro‑oculo‑facial‑skeletal syndrome—often shortened to COFS syndrome—is a very rare, inherited, degenerative disorder that damages the brain, eyes, face, ...
Cerebral Visual Impairment (CVI)—sometimes called cortical visual impairment—is a brain‑based sight problem. The eyes themselves may be healthy, but the parts ...
Cerebral Venous Sinus Thrombosis is a rare type of stroke in which a blood clot forms inside the large collecting veins (dural venous sinuses and cortical ...
Cerebral venous and dural sinus thrombosis—often shortened to CVST or “dural‑sinus clot”—is a rare, potentially life‑threatening kind of stroke that happens ...