McDonald diagnostic criteria for multiple sclerosis are MRI criteria used in the diagnosis of multiple sclerosis (MS) were introduced in 2001, revised in 2005 and again recently in 2010.
This latest revision improves sensitivity from 46% to 77% with a slight tradeoff in specificity (slight deterioration from 94% to 92%), with an overall accuracy of 86% 2. For the previous criteria please see McDonald diagnostic criteria 2001-2005.
As before the diagnosis of multiple sclerosis requires establishing disease disseminated in both space and time.
Dissemination in space
Dissemination in space requires ≥1 T2 bright lesions in two or more of the following locations 1:
- spinal cord
- if a patient has a brainstem / spinal cord syndrome, the symptomatic lesion(s) are excluded from the criteria, not contributing to the lesion count
Dissemination in time
Dissemination in time can be established in one of two ways:
- a new lesion when compared to a previous scan (irrespective of timing)
- T2 bright lesion and/or gadolinium-enhancing
- presence of asymptomatic enhancing lesion and a non-enhancing T2 bright lesion on any one scan
Primary progressive multiple sclerosis (PPMS)
In addition to the above criteria, the diagnosis of primary progressive multiple sclerosis has also been revised. The diagnosis now requires:
- ≥1 year of disease progression (this can be determined either prospectively or retrospectively)
- plus two of the following three criteria