The diagnosis of primary progressive multiple sclerosis

A diagnostic approach to primary progressive multiple sclerosis. The diagnostic algorithm is adapted from that suggested by Thompson et al. [16]. Central to the approach is sound differential diagnosis to exclude competing conditions. The major split in the flow diagram is a demonstration of intrathecal immunoglobulin synthesis as either the presence of cerebral spinal fluid (CSF)-specific oligoclonal bands or elevated IgG index. Lesion requirements for definite neuroimaging findings (MRI+) and supportive but not fully conclusive neuroimaging findings (MRI+/−) are detailed in the text. Only convincing findings on visual-evoked responses (VER) contribute to this flow scheme. The presence or absence of these findings lead through the flow diagram to varying levels of diagnostic certainty including definite (PPMS), probable (prob PPMS), possible (pos PPMS) and not primary progressive MS (PPMS).