Table 1 CT scan parameters

Patient position: Head first supine

Range: 3 cm cranial of umbilicus to symphysis

Bolus tracking: Abdominal aorta 2 cm cranial to bifurcation

Contrast medium: 120 mL Ultravist 370 or Iomeron 350, 4.0 mL/s

Voltage: 120 kV

Current: 150–200 mA

Slice collimation: 0.75 mm

Kernel: B20f medium

Slice width/increment: 1.0 mm/0.7 mm reconstruction