clinically isolated syndrome
Clinically isolated syndrome (CIS) is the first episode suggestive of demyelination . It can either be monofocal (single lesion) or multifocal . Not all patients with CIS will go on to develop multiple sclerosis however if at presentation there are changes on MRI suggestive of MS, then the chances of progressing to MS are high .
Latest McDonalds criteria (2017) allows an early diagnosis to be made solely on basis of dissemination in space on MRI, and the presence of CSF-specific oligoclonal bands, without the need for demonstration of dissemination in time on MRI.