A 23-year-old woman complains of progressive loss of vision and papilledema. Investigations show normal findings on CT scan. A lumbar puncture shows marked elevation of pressure. What is the most likely diagnosis?

Pseudotumor cerebri is a condition that most commonly occurs in young adults, particularly in females. In this condition, ICP as measured by a lumbar puncture is elevated, while the size of the cerebral ventricles on imaging studies is small or normal. It is a generally progressive condition that causes headache and damage to the optic nerve, sometimes leading to loss of peripheral vision and blindness.