An optic nerve glioma is a tumor that grows from the support cells of the optic pathway, which is the “wire” that carries visual signals from the eye to the ...

Noonan syndrome is a genetic condition. It affects many parts of the body. It changes how a child grows and develops. It often causes a special look to the ...

Neurofibromatosis is a group of genetic conditions. In these conditions, small mistakes in certain genes make cells in nerves grow in the wrong way. This can ...

Neuroblastoma is a cancer that starts in very young nerve cells. These young nerve cells are called “neuroblasts.” They are baby cells of the sympathetic ...

A ganglioglioma is a rare brain or spinal cord tumor. It has two parts in the same lump. One part is made of nerve cells (ganglion cells). The other part is ...

Choroid plexus papilloma (CPP) is a rare, usually benign (non-cancer) brain tumor that starts in the choroid plexus, the spongy tissue inside the brain’s fluid ...

Pilomyxoid astrocytoma is a rare brain tumor that starts from star-shaped support cells in the brain called astrocytes. Doctors first recognized it as a tumor ...

Merkel cell carcinoma (MCC) is a rare but very aggressive skin cancer that starts in the top layer of the skin. Under the microscope it looks like a “small ...

Medulloepithelioma is a very rare eye tumor that starts from the non-pigmented ciliary epithelium—a thin inner lining in the front part of the eye that helps ...

Malignant optic glioma is a cancer of the optic pathway (the cable system that carries visual signals from the eyes to the brain). In simple terms, “malignant” ...

Malignant melanoma of the eyelid is a dangerous skin cancer that starts in pigment-making cells (melanocytes) located in the thin skin of the upper or lower ...

Your tear system is a small plumbing network. Tears flow from the eye corners through two tiny holes (puncta), into short channels (canaliculi), down into a ...

A lacrimal sac papilloma is a papilloma that grows from the lining of the tear drainage sac. The sac lining is “respiratory-type” mucosa (similar to nasal ...

The lacrimal gland is the tear-making gland. You have one above each eye, tucked into the outer (temporal) corner of the upper eyelid. It sits in a shallow ...

A circumscribed choroidal hemangioma is a benign (non-cancerous) blood-vessel tumor that grows inside the choroid, the spongy, vascular layer underneath your ...

Diffuse choroidal hemangioma is a birth-related (congenital) cluster of extra blood vessels inside the choroid, which is the thin, spongy, reddish layer of ...

Retinal vasoproliferative tumor (often shortened to VPT) is a rare, usually benign (non-cancer) lump that grows in the peripheral retina (the outer edge of the ...

A choroidal vasoproliferative tumor—more commonly called a retinal vasoproliferative tumor (VPT)—is a benign (non-cancer) lump made mostly of new blood vessels ...

A retinal angioma, also known as a retinal capillary hemangioma, is a rare, non-cancerous (benign) growth made up of extra blood vessels in the retina—the ...

A racemose hemangioma (RH) is a fast-flow vascular malformation, not a true tumor. Doctors also call it a retinal or iris arteriovenous malformation (AVM) when ...