Papilledema and idiopathic intracranial hypertension
A detailed ophthalmic examination, including perimetry, is critical to the evaluation, treatment, and assessment of treatment response in patients with papilledema 1).
Physical examination of the nervous system is typically normal. apart from the presence of papilledema, with 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. Longstanding papilledema leads to optic nerve atrophy, in which the disc looks pale and visual loss tends to be advanced.
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
Papilledema is the hallmark sign of IIH. It occurs due to raised ICP transmitted to the optic nerve sheath. The elevated pressure, in turn, disrupts the axoplasmic flow within the nerve, resulting in swelling of the axons and leakage of water, protein, and other cellular content into the extracellular space of the optic disc, leading to optic disc edema 2)
The presence of papilledema certainly supports the diagnosis of IIH, but is not a formal part of the ICHD-3b diagnostic criteria for IIH. As such, the absence or inability of a provider to appreciate papilledema should not delay .further evaluations.
Although the majority of patients with IIH have papilledema, IIH without papilledema can occur 3).