title: Twenty classic signs in neuroradiology: A pictorial essay.
abstract: In this article we describe 20 classic signs in neuroradiology and provide illustrations of each; we also discuss the causes for their appearance, their reliability and sensitivity, and the differential diagnoses to be considered when they are encountered on imaging.
authors.affiliation: Department of Diagnostic Imaging, Hospital for Sick Children, University of Toronto, 555, University Avenue, Toronto, Ontario M5G 1X8, Canada.
authors.forename: Govind B
authors.initials: GB
authors.lastname: Chavhan
authors.forename: Manohar M
authors.initials: MM
authors.lastname: Shroff