[1] Hosp Univ San Ignacio Pontificia Univ Javeriana, Dept Radiol, Radiol, Country Scan Ltda,Carrera 7 40-62, Bogota 110231, Colombia
[2] Washington Univ, Mallinckrodt Inst Radiol, Cardiothorac Imaging Sect, Dept Radiol, St Louis, MO USA
[3] Ctr Diagnostico Rossi, Dept Radiol, Buenos Aires, DF, Argentina