Papilledema - swelling of the optic disk, the point at which the OPTIC NERVE enters the RETINA, that results from increased pressure within the skull. Papilledema typically signals serious neurologic damage such as STROKE or TRAUMATIC BRAIN INJURY (TBI) that causes bleeding (HEMORRHAGE), brain tumor, extreme HYPERTENSION, or inflammatory INFECTION such as ENCEPHALITIS and MENINGITIS. Though papilledema is not a disorder of the EYE, untreated it will result in complete loss of vision because the swelling interrupts the flow of blood to the optic NERVE.
Doctors check for any signs of papilledema during a routine OPHTHALMIC EXAMINATION, as often papilledema is an early sign of a neurologic problem. The need for intervention to relieve the intracranial pressure is urgent, not only to preserve vision but also often as a lifesaving measure. The nature of the intervention depends on the underlying cause. Extremely elevated blood pressure points to hypertension as the cause; other causes require NEUROLOGIC EXAMINATION for further evaluation and diagnosis. With prompt treatment to reduce the intracranial pressure, papilledema typically resolves in about six to eight weeks and vision, if affected, returns to its previous level.
Swelling around the optic disk may occur for various reasons that are not the result of increased intracranial pressure. These are usually ophthalmologic in nature, such as GLAUCOMA and ISCHEMIC OPTIC NEUROPATHY. The conditions threaten vision, but they are not life-threatening.
See also OPTIC NERVE ATROPHY; RETROBULBAR OPTIC NEURITIS; TOXIC OPTIC NEUROPATHY.
Resource: Facts On File Encyclopedia Of Health And Medicine
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