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  • Review Article
  • Published:

The current role of MRI in differentiating multiple sclerosis from its imaging mimics

An Erratum to this article was published on 20 March 2018

This article has been updated

Key Points

  • MRI is crucial in the diagnosis of multiple sclerosis (MS), revealing the dissemination in space and time of white matter lesions (WMLs) and helping to rule out alternative diagnoses

  • WMLs with a distribution similar to that seen in MS can occur in many disorders, from common age-related vascular disease and migraine to neuromyelitis optica spectrum disorders and rarer conditions

  • The distribution of WMLs can help to differentiate MS from antibody-mediated CNS disorders

  • The proportion of lesions that exhibit the central vein sign and the presence of cortical lesions can be useful in differentiating MS from some of its mimics

  • Meningeal enhancement, indistinct (ill-defined) lesions that increase in size over time, macrobleeds and microbleeds, infarcts, cavities, symmetrical lesions that spare U-fibres, siderosis and extensive spinal cord lesions suggest diagnoses other than MS

  • We suggest the mnemonic iMIMICs to remember the atypical MRI features that indicate a diagnosis other than MS

Abstract

MRI red flags proposed over a decade ago by the European Magnetic Resonance Network in MS (MAGNIMS) have guided clinicians in the diagnosis of multiple sclerosis (MS). However, the past 10 years have seen increased recognition that vascular disease can coexist and possibly interact with MS, improvements in the reliability of ways to differentiate MS from novel antibody-mediated CNS disorders (such as anti-aquaporin-4 antibody and myelin-oligodendrocyte glycoprotein antibody-associated diseases) and advances in MRI techniques. In this Review, MAGNIMS updates the imaging features that differentiate the most common mimics of MS, particularly age-related cerebrovascular disease and neuromyelitis optica, from MS itself. We also provide a pragmatic summary of the clinically useful MRI features that distinguish MS from its mimics and discuss the future of nonconventional techniques that have identified promising disease-specific features.

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Figure 1: Typical imaging features of multiple sclerosis with conventional MRI and possible differentiating features with nonconventional MRI.
Figure 2: Use of the iMIMICs mnemonic in the differential diagnosis of multiple sclerosis using MRI.
Figure 3: Age-related white matter lesions and cerebrovascular disease lesions.
Figure 4: Neuromyelitis optica spectrum disorder brain lesions.
Figure 5: Imaging features of other multiple sclerosis mimics.

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Change history

  • 27 March 2018

    In the version of this article originally published online, the heading of the third column in Table 1 was "Percentage of lesions that meet criteria". This heading should be "Percentage of patients that meet criteria". The error has been corrected in the print and online versions.

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Acknowledgements

The authors would like to thank Ricardo Franca for his help with the design of Figure 2.

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R.G., O.C., F.B., C.E., M.H., F.P., P.P., A.R., N.E. and J.P. researched data for the article. R.G., O.C., F.B., M.F., F.P., P.P., A.R., N.E. and J.P. made substantial contributions to discussion of the content. R.G., O.C., F.B., F.P., P.P., N.E. and J.P. wrote the article. All authors reviewed and edited the article before submission.

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Correspondence to Jacqueline Palace.

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M.H., G.C.D. and F.F. declare no competing interests. R.G. has received support for scientific meetings and courses and honoraria for advisory work from Bayer, Biogen, Merck, Novartis. O.C. serves as a consultant for Biogen, Novartis and General Electric, for which honoraria are all paid to the University College London Institute of Neurology. F.B. serves as a consultant for Biogen, Bayer, Genzyme, Jansen Research, Merck, Novartis, Roche, Synthon BV and Teva. N.D.S. has received honoraria from Biogen, Genzyme, Merck, Novartis, Schering and Teva for consulting services, speaking and travel support. He serves on advisory boards for Biogen, Merck and Novartis. C.E. has received funding for travel and speaker honoraria from Biogen, Bayer, Genzyme, Merck, Novartis, Shire and Teva, funding for research from Biogen, Merck and Teva, and has served on scientific advisory boards for Bayer, Biogen, Merck, Novartis, Roche and Teva. M.F. serves on a scientific advisory board for Teva, has received compensation for consulting services and/or speaking activities from Biogen, Merck, Novartis and Teva, and has received research support from Biogen, Novartis and Teva. F.P. has served on scientific advisory boards for MedImmune and the Novartis OCTIMS study, has received travel funding and/or speaker honoraria from Alexion-Chugai, Bayer, Biogen, MedImmune, Merck, Novartis, Sanofi, Shire Pharmaceuticals and Teva, has consulted for Alexion, Biogen, MedImmune, Sanofi and Shire Pharmaceuticals, and has received research support from Alexion, Bayer, Biogen, Merck, Novartis, Sanofi and Teva. P.P. has received speaker honoraria from Biogen, EXCEMED and Novartis. A.R. serves on scientific advisory boards for Novartis, OLEA Medical and Sanofi, has received speaker honoraria from Bayer, Biogen, Bracco, Merck, Novartis, Roche, Sanofi and Teva, and has research agreements with Siemens AG. L.K.'s institute (University Hospital Basel, Switzerland) has received, and used exclusively for research support, steering committee, advisory board and consultancy fees from Actelion, Addex, Bayer, Biogen, Biotica, Genzyme, Eli-Lilly, Merck, Mitsubishi, Novartis, Ono Pharma, Pfizer, Receptos, Sanofi, Santhera, Siemens, Teva, UCB and XenoPort, speaker fees from Bayer, Biogen, Merck, Novartis, Sanofi and Teva, support of educational activities from Bayer, Biogen, CSL Behring, Genzyme, Merck, Novartis, Sanofi and Teva, royalties from Neurostatus, and grants from Bayer Healthcare, Biogen, Merck, Novartis, Roche and Roche Research Foundations.T.Y. has received consultant, clinical trial or travel fees from Biogen, the European Society of Radiology, GlaxoSmithKline, IXICO, Novartis and Merck. J.F. has served on scientific advisory boards for, and received funding of travel for participation in scientific advisory boards and honoraria from, Biogen, Genzyme, Merck, Novartis, Sanofi, Takeda and Teva. C.G. has received compensation for consulting from Bayer and Biogen, and speaker fees for lectures from Biogen, Bayer, Genzyme, Merck, Novartis and Teva. C.G. has received speaker fees from Bayer, Biogen, Genzyme, Merck and Teva. J.S.-G. has received compensation for serving on scientific advisory boards or on speaker bureaus from Biogen, Merck, Novartis, Sanofi and Teva. N.E. has received honoraria from Biogen, Genzyme and Novartis for consulting services, speaking and travel support. He serves on advisory boards for Biogen, Merck and Novartis. J.P. has received support for scientific meetings and honoraria for advisory work from ABIDE, Alexion, Biogen, Bayer, Chugai Pharma, MedImmune, Merck, Novartis, Roche and Teva, and unrestricted grants from Bayer, Biogen, Merck and Novartis.

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Glossary

Dawson fingers

Elongated lesions along the subependymal veins, and thus perpendicular to the walls of the lateral ventricles, that are characteristic of MS.

Lacunae

Small (3–15 mm diameter) round or ovoid subcortical infarcts in the territory of one perforating arteriole with an MRI signal similar to that of CSF.

U-fibres

Short association fibres that connect adjacent gyri of the brain, located within the cortex or immediately beneath it in the outermost parts of the subcortical white matter.

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Geraldes, R., Ciccarelli, O., Barkhof, F. et al. The current role of MRI in differentiating multiple sclerosis from its imaging mimics. Nat Rev Neurol 14, 199–213 (2018). https://doi.org/10.1038/nrneurol.2018.14

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