A 19-year-old woman consulted the neurologist for headache and diplopia. Physical examination revealed no focal neurological findings except diplopia due to an abducens nerve paresis. Visual acuity and visual field examinations were normal. Fundoscopy showed bilateral papilledema. The patient was referred to our department for an MRI examination. MRI of the brain was revealed no intracranial mass lesion, hydrocephalia or venous sinus thrombosis. Additional T2 high resolution sequences of the orbits showed however tortuosity of the optic nerves with dilatation of the perioptic subarachnoidal spaces (arrows in Fig. A). Also flattening of the posterior sclera and protrusion of the optic nerve papilla into the posterior globes was seen (arrowheads in Fig. A). After gadolinium administration, T1WI of the orbits showed enhancement and protrusion of the prelaminar optic nerve (arrows in Fig. B). Based on the clinical and imaging findings the diagnosis of idiopathic intracranial hypertension was made. The diagnosis was confirmed by lumbar puncture with opening CSF pressure of 38 cm H2O. CSF was evacuated to a closing pressure of 15 cm H2O. The patient was also treated with Diamox and clinical symptoms gradually improved so the patient could be dismissed from hospital.