Association of MRI Findings and Visual Outcome in Idiopathic Intracranial Hypertension

• Authors: Amit Manohar Saindane, Emory University; Beau Benjamin Bruce, Emory University; Bryan D. Riggeal, Emory University; Nancy J Newman, Emory University; Valerie Biousse, Emory University
• Journal Title: American Journal of Roentgenology
• Volume: Volume 201, Number 2
• Publisher: American Roentgen Ray Society (ARRS) | 2013-08, Pages 412-418
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.2214/AJR.12.9638
• Subjects: Health Sciences, Radiology; Health Sciences, Opthamology; Biology, Neuroscience
• Keywords: CSF; idiopathic intracranial hypertension; intracranial pressure; MRI

Abstract

OBJECTIVE Patients with idiopathic intracranial hypertension (IIH) have elevated intracranial pressure (ICP) without identifiable cause. The clinical course is variable, resulting in irreversible vision loss in some, and a benign course in others. While MRI findings have been described in IIH, their association with visual outcome has not been evaluated. MATERIALS AND METHODS 46 patients with IIH underwent funduscopic evaluation, visual field testing, lumbar puncture with opening pressure (OP) measurement, and MRI. Patients were stratified into: Group 1: no vision loss (n=28), Group 2: some vision loss (n=10), and Group 3: severe vision loss (n=8). MRI findings in the orbits, pituitary gland, and optic canals, and frequency of skull base cephaloceles and transverse sinus stenosis (TSS) were assessed blinded to the patients’ visual outcome. Demographic, clinical, and MRI findings were evaluated for association with visual outcome. RESULTS Patients in group 3 (worst visual outcome) were significantly younger (P=0.03) and had higher OP (P=0.04) than the other groups. There were no significant differences in gender, race, or body mass index. Despite worse visual outcomes and sometimes fulminant vision loss, there were no differences in the frequency of orbital MRI findings, TSS, or in optic canal diameter and pituitary appearance among the three groups. Group 3 had significantly lower cephalocele frequency than the other groups (P=0.04). CONCLUSION While MRI findings may suggest elevated ICP and the diagnosis of IIH, they are not predictive of visual outcome in IIH.