Brain versus orbital MRI in evaluating idiopathic intracranial hypertension

Objective: To evaluate the usefulness of brain MRI ascompared to orbital MRI in the assessment of idiopathicintracranial hypertension (IIH).Methods: The study was carried out at KingAbdul-Aziz University Hospital, Jeddah, Kingdom ofSaudi Arabia between January 2002 and December 2003.An MRI of the head and orbits was performed for 42patients with the clinical diagnosis of IIH, and 15 normalvolunteers. All cases of secondary increased intracranialpressure were eliminated. The images were evaluated forthe presence of empty sella, parenchymal abnormalities,ventricular and sulcal size changes, optic disc elevation,and optic nerve sheath distention.Results: The MRI of the head revealed empty sella in29 patients and in one normal volunteer. Brain MRI didnot reveal any parenchymal, ventricular or cisternalabnormalities in either group. Orbital MRI revealed opticnerve sheath distension and optic disc elevation in 36patients, and were normal in all volunteers.Conclusion: Brain MRI has limited value in theevaluation of IIH. Orbital MRI is the recommendedimaging modality for this entity.