Published ahead of print on January 14, 2010 doi: 10.3174/ajnr.A1934 American Journal of Neuroradiology 31:E30, February 2010 © 2010 American Society of Neuroradiology L.E. Ginsberga, G.I. Claymanb, B.S. Edeiken-Monroec, E. Rohrend andS.I. Shermane aProfessor of Radiology and Head and Neck Surgery Diagnostic Radiology bA.J.