Contrast-enhanced fat-suppressed FLAIR for the characterization of leptomeningeal inflammation in optic neuritis

• Published in: Multiple sclerosis Vol. 25; no. 6; pp. 792 - 800
• Main Authors: Pino-Lopez, Luis, Wenz, Holger, Böhme, Johannes, Maros, Máté, Schlichtenbrede, Frank, Groden, Christoph, Förster, Alex
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01-05-2019; Sage Publications Ltd
• Subjects: Adult; Biomarkers; Cerebrospinal fluid; Female; Humans; Image Enhancement; Inflammation; Magnetic Resonance Imaging; Male; Meninges; Meninges - diagnostic imaging; Middle Aged; Multiple sclerosis; Neuritis; Neuroimaging; NMR; Nuclear magnetic resonance; Optic neuritis; Optic Neuritis - diagnostic imaging; Young Adult; FLAIR; Contrast-enhanced; leptomeningeal inflammation; fat-suppressed; optic neuritis
• ISSN: 1352-4585; 1477-0970
• DOI: 10.1177/1352458518770268

Background:
Leptomeningeal contrast enhancement on fluid-attenuated inversion recovery (FLAIR) images has been reported in patients with multiple sclerosis and interpreted as a biomarker of inflammation. In this study, we sought to evaluate this phenomenon in patients with optic neuritis (ON).
Methods:
A total of 42 patients with suspected ON were included in this prospective study and underwent a dedicated study magnetic resonance imaging (MRI) protocol including native and contrast-enhanced fat-suppressed thin-section axial and coronal FLAIR images on an 1.5 T magnetic resonance (MR) system.
Results:
After diagnostic workup, 34 patients with final diagnosis of ON were analyzed in detail. On contrast-enhanced fat-suppressed FLAIR images, 25 (73.5%) patients with ON demonstrated perioptic leptomeningeal enhancement, and in 3 (8.8%) patients, this was even the only pathological MRI finding. In comparison, patients with perioptic leptomeningeal enhancement on contrast-enhanced fat-suppressed FLAIR images had a higher prevalence of additional hyperintense brain lesions (p = 0.022) as well as cerebrospinal fluid (CSF)-specific oligoclonal bands (p = 0.013) than patients without.
Conclusion:
Perioptic leptomeningeal contrast enhancement on fat-suppressed FLAIR images is a novel marker in ON and possibly reflects a leptomeningeal inflammatory process preceding or accompanying ON. Thin-section contrast-enhanced fat-suppressed FLAIR images might be a useful addition in MRI protocols for patients with suspected ON.