MRI red flags may help avoid misdiagnosis of MS

A workshop of the European Magnetic Resonance Network in Multiple Sclerosis (MAGNIMS) has developed a series of 'red flags' for use alongside MS diagnostic criteria to alert clinicians to possible alternative diagnoses.Reporting the workshop conclusions in a recent issue of Lancet Neurol, the authors explain that there have been substantial efforts to define diagnostic criteria for MS, but the development of a set of "exclusion criteria" has received less attention. They say the red flags, which constitute a set of MRI features atypical for MS and suggestive of an alternative diagnosis, may help prompt clinicians to reconsider the differential diagnosis and "should represent the first step beyond the concept of 'no better explanation'". In the report, MRI red flags suggestive of an alternative diagnosis are categorised according to whether the lesion is in brain white matter, cortical grey matter, deep grey matter, spinal cord, or other. The authors explain that this approach resembles clinical practice more closely than using a disease-centred categorisation system. However, the authors also take a more systematic approach by providing more details of the red flags in the context of disorders that mimic MS. The authors say the red flags help take full advantage of the potential of MRI, reducing the chance of false-positive MS diagnoses while facilitating the correct diagnosis of other disorders. Thus, in patients positive for the International Panel criteria with no MRI red flags, a diagnosis of MS can be made. However, patients positive for the International Panel criteria with at least one MRI red flag would require additional tests to rule out other conditions. Reference...