RT Journal Article SR Electronic T1 CT angiography of the circle of Willis: is spiral technology always necessary? JF American Journal of Neuroradiology JO Am. J. Neuroradiol. FD American Society of Neuroradiology SP 1794 OP 1797 VO 18 IS 9 A1 Brown, J H A1 Lustrin, E S A1 Lev, M H A1 Taveras, J M YR 1997 UL http://www.ajnr.org/content/18/9/1794.abstract