Papilledema represents swelling of the optic nerve head due to increased what?

• A. Increased intraocular pressure
• B. Increased intracranial pressure
• C. Retinal detachment
• D. Optic neuritis

Answer: (B)

Papilledema is swelling of the optic nerve head caused by raised intracranial pressure. When intracranial pressure increases, this pressure is transmitted along the optic nerve’s surrounding subarachnoid space to the optic nerve head. That pressure disrupts axoplasmic flow in the nerve fibers as they pass through the lamina cribrosa and leads to edema and swelling of the optic disc. This mechanism is distinct from issues caused by the eye’s own pressure, such as glaucoma, where high intraocular pressure damages the optic nerve but doesn’t produce the same optic disc swelling pattern linked to intracranial pressure. Retinal detachment involves separation of the retina from underlying tissue, not swelling of the optic nerve head. Optic neuritis is inflammation of the optic nerve, typically with painful vision loss, rather than edema from ICP.