What is Papilledema?
Papilledema is optic disc swelling (usually bilateral) caused by elevated intracranial pressure, which can lead to permanent vision loss if the underlying condition is not treated. 1, 2
Definition and Pathophysiology
Papilledema specifically refers to swelling of the optic disc—the point where the optic nerve exits the eye—resulting from increased intracranial pressure transmitted through the cerebrospinal fluid surrounding the optic nerve. 1, 3, 4 The mechanism involves interruption of axoplasmic flow within the optic nerve, which is an energy-dependent process, leading to intraneuronal ischemia and potential permanent optic nerve damage. 5, 3
Clinical Presentation
Visual Symptoms
- Transient visual obscurations occur in the majority of patients—these are temporary episodes of blurred or lost vision lasting seconds, caused by transient ischemia of the optic nerve head from increased tissue pressure. 6
- Early in the disease, central vision, visual acuity, and color vision are typically preserved, though peripheral visual field defects may develop. 4, 7
- Progressive visual loss can occur with chronic papilledema if untreated. 3
Associated Symptoms
- Headache is present in nearly 90% of patients with idiopathic intracranial hypertension. 6
- Nausea and vomiting from elevated intracranial pressure. 4
- Pulsatile tinnitus (whooshing sound in the ears). 6
- Diplopia (double vision), often from sixth cranial nerve palsy. 1, 4
- Ataxia, altered consciousness, or other neurological symptoms depending on the underlying cause. 4
Fundoscopic Examination Findings
The optic disc demonstrates characteristic changes: 4
- Elevation and blurring of the disc margins
- Venous congestion and engorgement
- Retinal splinter hemorrhages near the disc
- Hard exudates and retinal infarcts
- Loss of the normal foveal depression
- Absence of spontaneous venous pulsations (though their presence doesn't exclude papilledema)
Common Causes
Primary Causes
- Idiopathic intracranial hypertension (pseudotumor cerebri): predominantly affects overweight women of childbearing age. 1, 3
- Intracranial mass lesions: tumors, abscesses. 1, 4
- Cerebral venous sinus thrombosis: requires urgent diagnosis and anticoagulation. 1, 8
- Intracranial infections: meningitis, encephalitis. 5, 4
- Subarachnoid hemorrhage and subdural hematoma. 4
Medication-Induced
Growth hormone therapy can cause or worsen papilledema by increasing intracranial pressure, which is why fundoscopic examination is recommended before initiating treatment. 1 Other medications include tetracyclines, vitamin A, retinoids, steroids, thyroxine, and lithium. 9
Critical Diagnostic Pitfalls
Papilledema can be asymmetric or rarely unilateral, which may lead to misdiagnosis as optic neuritis or other optic neuropathies. 5, 7 Patients with indwelling CSF shunts, tuberous sclerosis, or chronic granulomatous meningitis require periodic examination because imaging may fail to show conventional signs of elevated intracranial pressure despite true papilledema. 5
Vitreopapillary traction from vitreous adhesion around the optic nerve can mimic papilledema on examination and should be distinguished using optical coherence tomography. 1
Prognosis and Complications
The major morbidity is permanent vision loss from chronic axoplasmic flow stasis and optic nerve ischemia. 3 Vision loss can be irreversible if treatment is delayed, making prompt recognition and management essential. 1, 2 Some patients may present with acute visual loss despite disc swelling, which can be mistaken for optic neuritis rather than papilledema. 7