(ii) at least two or more of the following neuroimaging signs: bilateral transverse sinus stenosis, empty sella, posterior sclera flattening, perioptic subaracnoid space distension; vertical tortuosity of the orbital optic nerve, tonsillar ectopia; (iii) altered pressure parameters for stage 1 or stage 2 of CSF hypertension; (iv) normal CSF contents; (v) symptoms relieved by a reduction in CSF pressure.