Idiopathic intracranial hypertension (IIH) is defined as intracranial pressure (ICP) greater than 25 cmH2O, with a constellation of clinical and radiographic findings including permanent vision loss, venous sinus thrombosis and hydrocephalus respectively. An MRI brain with optic nerve diffusion restriction can add to the diagnostic yield in difficult cases. 

A 27-year old, female, at 16-weeks gestation presented with a 2-week history of holo-cephalic positional headache, peripheral vision loss and diplopia. Past history was suggestive of miscarriages and gestational hypertension, She reported constant, severe bi-temporal headache worse with lying flat, visual acuity was 20/50 OD and 20/30 OS with visual obscurations. Multiple attempts to a successful fundoscopic exam revealed bilateral grade IV papilledema with markedly elevated optic disc margins and scattered peri-papillary exudates, flame hemorrhages and 3+ humping of the vessels concerning . A subsequent MRI brain wo contrast showed restricted diffusion involving both the optic discs, in addition to flattening of the globe, empty sella, and slit ventricles. An MRV demonstrated bilateral transverse sinus stenosis. She underwent a lumbar puncture with an ICP elevated at greater than 55cmH2O, with a negative CSF analysis. Immediate management with high-dose Acetazolamide was started. Venous stenting was deferred until after delivery. Plan for neurosurgical intervention with right ventriculo-atrial shunt was executed with headache resolution but no changes in vision. She followed up with her ophthalmologist, visual fields showed nerve fiber layer defects with papilledema without vision improvement.