Idiopathic intracranial hypertension: Imaging and clinical fundamentals

Table 2 Diagnostic criteria for idiopathic intracranial hypertension

	Diagnostic criteria for idiopathic intracranial hypertension1
I	Papilledema
II	Normal neurologic examination excepting abnormalities of the cranial nerves (VIth or VIIth nerve dysfunction)
III	Neuroimaging: Normal brain parenchyma without signs of hydrocephalus, mass, structural lesions, or abnormal meningeal enhancement on MRI (performed with and without gadolinium) for typical patients (female and obese), and on MRI (performed with and without gadolinium) along with MRV for other patients; if MRI is unavailable or contraindicated, a contrast-enhanced CT may serve as an alternative
IV	Normal CSF composition
V	Increase LP opening pressure [≥ 250 mm CSF in adults and ≥ 280 mm CSF in children (250 mm CSF if the child is not sedated and not obese)] in an appropriately performed LP
Neuroimaging criteria	A: Empty sella
	B: Posterior globe flattening
	C: Optic nerve sheath distention (with or without optic nerve tortuosity)
	D: Transverse venous sinus stenosis

¹Criteria: (1) An idiopathic intracranial hypertension (IIH) diagnosis is confirmed if criteria I-V are met; (2) If only criteria I-IV are met, then IIH diagnosis is probable; (3) If criteria I (papilledema) is not met, an IIH diagnosis can be made if criteria II–V are met, and the patient demonstrates a unilateral or bilateral abducens nerve palsy; and (4) If criteria I (papilledema) is not met and there is no abducens nerve palsy, an IIH diagnosis can be suggested (but not made) if criteria II-V are met, and also at least 3 of the 4 neuroimaging criteria (A-D) are met.

Adapted from Friedman et al[1]. MRI: Magnetic resonance imaging; MRV: Magnetic resonance venography; CT: Computed tomography; LP: Lumbar puncture; CSF: Cerebrospinal fluid.