MRI features of pediatric multiple sclerosis

Magnetic resonance imaging (MRI) is considered an essential tool in the diagnosis and management of patients with multiple sclerosis (MS), mostly due to its high sensitivity to depict white matter lesions and characterize disease dissemination in space and time. However, the standardization of its interpretation in adult patients with MS has not yet been paralleled in the pediatric population. For instance, until recently, the diagnosis of MS in the pediatric population did not include MRI criteria as it does in adults [1–4]. This is despite the fact that MRI has been studied for more than 20 years in the diagnosis of MS in pediatric patients [5]. Similarly, the operational definitions for pediatric-onset MS [6] that aim at creating a uniform terminology to be used in future prospective studies rely on the adult MRI criteria, not specific pediatric ones (see Chapter 2). MS in children has several characteristic features, including an almost exclusive relapsing–remitting course of disease [7,8] with more frequent relapses and seizures [9]. Involved anatomical regions differ somewhat in children and adults, with children showing more frequent involvement of the posterior fossa, and less frequent involvement of the spinal cord, although this remains to be confirmed [10]. These particularities raise questions about the ability to use the same diagnostic criteria in the children and adults with MS, especially in prepubertal patients in whom the clinical, biological, and radiological presentation seem to be distinct [11–13].