RT Journal Article SR Electronic T1 Reply JF American Journal of Neuroradiology JO Am. J. Neuroradiol. FD American Society of Neuroradiology SP 1187 OP 1187 VO 20 IS 6 A1 David M. Yousem YR 1999 UL http://www.ajnr.org/content/20/6/1187.2.abstract