[1] ST LOUIS CHILDRENS HOSP, DIV PEDIAT NEUROL, ST LOUIS, MO 63178 USA
[2] WASHINGTON UNIV, SCH MED, EDWARD MALLINCKRODT INST RADIOL, ST LOUIS, MO 63130 USA
[3] WASHINGTON UNIV, SCH MED, EDWARD MALLINCKRODT INST RADIOL, EDWARD MALLINCKRODT DEPT PEDIAT, ST LOUIS, MO 63130 USA
[4] WASHINGTON UNIV, SCH MED, EDWARD MALLINCKRODT INST RADIOL, DEPT NEUROL & NEUROSURG NEUROL, ST LOUIS, MO 63130 USA