[1] Univ Basel Hosp, Clin Radiol & Nucl Med, Basel, Switzerland
[2] Univ Basel Hosp, Dept Angiol, Basel, Switzerland
[3] Univ Basel Hosp, Clin Radiol & Nucl Med, Div Radiol Phys, Basel, Switzerland
[4] Radiol Clin Hirslanden, Zurich, Switzerland
[5] Univ British Columbia, Vancouver Gen Hosp, Dept Radiol, Vancouver, BC, Canada
[6] Hirslanden Clin St Anna, Dept Radiol & Nucl Med, Luzern, Switzerland
[7] Univ Wisconsin, Dept Radiol, 600 Highland Ave,E1-374, Madison, WI 53792 USA