[1] Washington Univ, Dept Biomed Engn, St Louis, MO USA
[2] Washington Univ, Sch Med, Mallinckrodt Inst Radiol, St Louis, MO USA
[3] Washington Univ, Sch Med, Dept Pediat, St Louis, MO 63110 USA
[4] Washington Univ, Sch Med, Dept Neurol, St Louis, MO 63110 USA
[5] Brigham & Womens Hosp, Dept Pediat Newborn Med, 75 Francis St, Boston, MA 02115 USA