Suggested CT scanning protocol*

Patient orientationSupine, feet first
Gantry tilt
Region of interestInitial exam: mid-T12 to mid-sacrum
Subsequent exams: One level above to one level below fusion level(s)
Kernel/algorithmB80/bone
Milliamperage (mA)250
Kilovoltage (kV)140
Field of view (FOV)14 cm
Matrix512 × 512
Volume acquisition slice collimation1.0 mm
Image reconstruction progression
    Step 1Reconstructed axial 3.0-mm-thick sections; entire scan volume
    Step 2Reconstructed axial 1.0-mm-thick sections at 0.5-mm increments (overlapped); region of interest only
    Step 3Reformatted images in 3 planes; region of interest; 1.0 mm axial (parallel to the disc); 3.0 mm coronal and sagittal
    Window and level settings2000–3000/350–400
  • * Multisection (4) CT scanner.