Some neurological diseases that have signs that show up in the eyes. Papilledema (this photo) is often a sign of increased pressure inside of the head. Causes may include: brain tumor, bleeding, and idiopathic intracranial hypertension. Optic neuritis (an inflammation of the optic nerve) is often the first sign of multiple sclerosis. Ischemic optic neuropathy (there are several types) is basically a stroke of the optic nerve. Causes can range from inflammation, to clot, to lack of blood supply. Neuroretinitis is a broad spectrum disease that includes inflammation of the optic nerve and the retina. Two causes are cat scratch fever and tick bite.