Long-term untreated papilledema leads to visual loss, initially in the periphery but progressively towards the center of vision.Physical examination of the nervous system is typically normal apart from the presence of papilledema, which is seen on examination of the eye with a small device called an ophthalmoscope or in more detail with a fundus camera. If there are cranial nerve abnormalities, these may be noticed on eye examination in the form of a squint (third, fourth, or sixth nerve palsy) or as facial nerve palsy. If the papilledema has been longstanding, visual fields may be constricted and visual acuity may be decreased. Visual field testing by automated (Humphrey) perimetry is recommended as other methods of testing may be less accurate. Longstanding papilledema leads to optic atrophy, in which the disc looks pale and visual loss tends to be advanced. Causes
"Idiopathic" means of unknown cause. Therefore, IIH can only be diagnosed if there is no alternative explanation for the symptoms. Intracranial pressure may be increased due to medications such as high-dose vitamin A derivatives (e.g., isotretinoin for acne), long-term tetracycline antibiotics (for a variety of skin conditions) and hormonal contraceptives. There are numerous other diseases, mostly rare conditions, that may lead to intracranial hypertension. If there is an underlying cause, the condition is termed "secondary intracranial hypertension". Common causes of secondary intracranial hypertension include obstructive sleep apnea (a sleep-related breathing disorder), systemic lupus erythematosus (SLE), chronic kidney disease, and Behçets disease. Mechanism
The cause of IIH is not known.
Clinical trial number NCT03500549 for "Study to Evaluate the Efficacy and Safety of APL-2 in Patients With Paroxysmal Nocturnal Hemoglobinuria (PNH)" at ClinicalTrials.gov