What are the causes of papilledema (optic disc swelling)?

From the Guidelines

Papilledema is primarily caused by increased intracranial pressure (ICP) that transmits to the optic nerve head, resulting in optic disc swelling, with the most common causes including space-occupying lesions, idiopathic intracranial hypertension, and cerebral venous thrombosis, as seen in a study published in 2024 1. The causes of papilledema can be categorized into several groups, including:

• Space-occupying lesions like brain tumors, cerebral edema, hydrocephalus, and intracranial hemorrhage
• Idiopathic intracranial hypertension (pseudotumor cerebri), particularly in young overweight women, as noted in a study published in 2018 1
• Inflammatory processes and increased ICP due to meningitis and encephalitis
• Certain medications, such as tetracyclines, vitamin A derivatives, and corticosteroid withdrawal, which can induce papilledema
• Venous sinus thrombosis, which obstructs cerebrospinal fluid drainage, as discussed in a study published in 2011 1
• Malignant hypertension, which can cause papilledema through severe blood pressure elevation
• Obstructive sleep apnea, increasingly recognized as a contributor through nocturnal CO2 retention and cerebral vasodilation The underlying mechanism involves blocked axoplasmic flow in the optic nerve due to increased pressure, leading to accumulation of axoplasm at the optic disc and subsequent swelling, as explained in a study published in 2018 1. Prompt identification of the cause is essential, as papilledema can lead to permanent vision loss if the underlying condition remains untreated. According to the most recent guidelines, patients with papilloedema should have regular follow-up and monitoring, including documentation of visual acuity, pupil examination, formal visual field assessment, dilated fundal examination, and BMI calculation, as recommended in a study published in 2018 1.

From the Research

Causes of Papilledema

The causes of papilledema can be categorized into several groups, including:

• Idiopathic intracranial hypertension (IIH) 2, 3, 4, 5
• Conditions that decrease cerebrospinal fluid (CSF) outflow, such as:
  • CSF derangements 2
  • Mechanical blockage of CSF outflow channels 2
• Conditions that increase CSF production, although this is rare 2
• Other causes, including:
  • Intracerebral mass lesions 5
  • Cerebral hemorrhage 5
  • Head trauma 5
  • Meningitis 5
  • Hydrocephalus 5
  • Spinal cord lesions 5
  • Impairment of cerebral sinus drainage 5
  • Anomalies of the cranium 5
  • Cerebral venous sinus thrombosis 3, 4

Pathogenesis of Papilledema

The pathogenesis of papilledema is complex and involves the transmission of elevated intracranial pressure to the subarachnoid space surrounding the optic nerve, which hinders axoplasmic transport within ganglion cell axons 2. The main mechanism of optic nerve damage is intraneuronal ischemia secondary to axoplasmic flow stasis 3, 5.

Diagnosis and Investigation

Diagnosis and investigation of papilledema typically involve a thorough ocular examination, including visual field testing, and ocular imaging such as color fundus photographs and optical coherence tomography 4. Joint care between ophthalmologists and neurologists is key to treating the underlying condition and managing any visual dysfunction and headache 4. Magnetic resonance imaging of the brain and orbits with venography sequences is the preferred neuroimaging modality to look for indirect imaging signs of increased intracranial pressure and to rule out nonidiopathic causes 2. Lumbar puncture with measurement of opening pressure and evaluation of CSF composition should also be performed 2.