Maria Ierardi was rendered wrongly in the original publication but has since been corrected. The publisher apologises for this error and the inconvenience caused. ... Radiology, University of Insubria , Viale Borri 57, 21100 Varese , Italy 1 Department of Radiology, BLuigi Sacco 2 University Hospital , Via G.B. Grassi 74, 20157 Milan , Italy - The name of the author Anna