CT pancreas (protocol)

Last revised by Raymond Chieng on 15 Apr 2023

The CT pancreas protocol serves as an outline for a dedicated examination of the pancreas. As a separate examination, it is usually conducted as a biphasic contrast study and might be conducted as a part of other scans such as  CT abdomen-pelvis, CT chest-abdomen-pelvis.

Note: This article aims to frame a general concept of a CT protocol for the assessment of the pancreas. Protocol specifics will vary depending on CT scanner type, specific hardware and software, radiologist and perhaps referrer preference, patient factors e.g. implants, specific indications.

A typical CT of the pancreas might look like as follows:

Typical indications include an evaluation of the following 1-4:

The purposes of a pancreatic CT includes the following 1-4:

  • patient position

    • supine position, abdomen centered within the gantry

    • both arms elevated

  • tube voltage

    • ≤120 kVp

  • tube current

  • scout

    • diaphragm to the iliac crest (or symphysis)

  • scan extent

    • arterial/pancreatic phase: mid diaphragm to the iliac crest

    • venous phase: above the diaphragm to the iliac crest, might be extended to include the whole pelvis

  • scan direction

    • craniocaudal

  • scan geometry

    • field of view (FOV): 350 mm (should be adjusted to increase in-plane resolution)

    • slice thickness: ≤0.625 mm, interval: ≤0.5 mm

    • reconstruction algorithm: soft tissue, bone​

  • oral contrast

    • neutral contrast agent: 800 ml water 20-30min before the scan

  • contrast injection considerations

    • non-contrast (rarely indicated)

    • biphasic pancreatic ± venous acquisition (to detect pancreatic mass) 1

      • contrast volume: 70-120ml  (1 mL/kg) with 30-40 mL saline chaser at 3-5 mL/s

      • optional bolus tracking: abdominal aorta

      • pancreatic phase: scan delay 15-20 sec after trigger or 35-40 sec after contrast injection 1

      • portal venous phase: 30 sec after the pancreatic phase or 65-70 sec after contrast injection 1

    • biphasic arterial ± venous acquisition (to detect neuroendocrine tumors) 1

      • contrast volume: 70-120ml  (1 mL/kg) with 30-40 mL saline chaser at 4-5 mL/s

      • bolus tracking: abdominal aorta

      • arterial phase: minimal scan delay (or 20 seconds after contrast injection) 1

      • portal venous phase: 40 seconds after the arterial phase or 60-70 seconds after contrast injection

    • single acquisition with a monophasic injection (venous phase)

      • contrast volume: 70-120ml  (1 mL/kg) with 30-40 mL saline chaser at 3-5 mL/s

      • portal venous phase: 65-70 sec after contrast injection

  • respiration phase

    • single breath-hold: inspiration

  • multiplanar reconstructions

    • axial images: strictly axial to the body axis

    • coronal images: strictly coronal to the body axis

    • sagittal images: strictly sagittal to the body axis, aligned through the center of the vertebral bodies and the sternum

    • slice thickness: soft tissue ≤2,5 mm, bone ≤2 mm overlap 20-40%

  • patient positioning prior to scanning might reduce and facilitate multiplanar reconstructions

  • depending on the exact indication the scan might require an extension of the scan field

  • consider coronal curved planar or paracoronal reformations

  • dual-energy CT with monochromatic reconstructions is thought to improve tissue contrast 5-7

  • dose optimization

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