This case demonstrates typical imaging features of ADEM, which although characterized as a

monophasic illness, individual lesions are not all at the same stage of evolution, thus some small or inapparent lesions early on can be seen to appear and mature even while other lesions regress. Additonally, relapsing forms of ADEM are certainly described (Relapsing disseminated encephalomyelitis (RDEM), and Multiphasic disseminated encephalomyelitis (MDEM)) although the demarcation between these and multiple sclerosis is contentious.

Importantly, this patient did not have relapsing / remitting long term course.