Schilder's disease, or myelinoclastic diffuse sclerosis, is a rare disorder characterised by an inflammatory white matter plaque of demyelination. Clinical signs and symptoms might be atypical for early multiple sclerosis and at imaging the lesion is easily taken for a brain tumour. Regardless of the use of Poser's criteria for clinical diagnosis of Schilder's disease proposed in 1986, diagnostic difficulties are still present, as evidenced by the many reported cases in the English literature revised (Pubmed indexed, period 1998-2008). It clearly emerges that neuroradiological features, observable in additional magnetic resonance sequences are crucial, besides the consideration of Poser's criteria, in differentiating between demyelinating lesions and brain tumours. A 29-year-old female patient is presented, where a careful evaluation of both the clinical and radiological features, which might have been at a first glance misleadingly suggestive for a brain tumour, allowed non-invasive diagnosis of Schilder's disease.