From the Guidelines
A CT pancreas protocol is a specialized computed tomography scan that involves multiple phases of imaging after intravenous contrast administration, typically including a non-contrast phase, arterial, pancreatic/late arterial, and portal venous phases, to capture the pancreas during different stages of enhancement. This protocol is different from a regular CT scan in that it uses thinner slice thickness (usually 1-3mm versus 5mm in standard CT) and may include specialized reconstruction techniques to better visualize the pancreatic parenchyma and ducts 1. The multi-phase approach is necessary because the pancreas enhances rapidly and differently than surrounding organs, and the difference in contrast enhancement between the parenchyma and adenocarcinoma is highest during the pancreatic phase, thereby providing a clear distinction between a hypodense lesion in the pancreas and the rest of the organ 1.
Key Differences from Regular CT
- Multiple phases of imaging after intravenous contrast administration
- Thinner slice thickness (usually 1-3mm versus 5mm in standard CT)
- Specialized reconstruction techniques to better visualize the pancreatic parenchyma and ducts
- Patients are typically asked to fast for 4-6 hours before the scan to reduce bowel motion and improve pancreatic visualization
- Water or negative oral contrast may be given rather than positive oral contrast used in regular abdominal CTs, as positive contrast can obscure subtle pancreatic findings
Clinical Value
The CT pancreas protocol is particularly valuable for detecting small pancreatic masses, assessing pancreatitis complications, and evaluating pancreatic ductal anatomy that might be missed on a standard single-phase CT scan 1. It is also useful for staging pancreatic cancer and determining resectability, with studies showing that 70% to 85% of patients determined by CT imaging to have resectable tumors were able to undergo resection 1.
From the Research
CT Pancreas Protocol
- A CT pancreas protocol is a specialized imaging protocol used to evaluate the pancreas and surrounding tissues [(2,3,4,5,6)].
- The protocol typically involves the use of a specific contrast agent and imaging parameters to optimize the visualization of the pancreas and detect any potential abnormalities.
Differences from Regular CT
- The main difference between a CT pancreas protocol and a regular CT scan is the use of a higher concentration of contrast agent and a faster injection rate to enhance the visualization of the pancreas [(4,5)].
- The CT pancreas protocol also typically involves imaging the pancreas during the arterial phase, which is the phase when the contrast agent is most concentrated in the arteries and provides the best visualization of the pancreas 6.
- The use of dual-energy CT and material decomposition algorithms can also be used to quantify iodine uptake and assess treatment response in patients with pancreatic cancer 3.
Imaging Parameters
- The imaging parameters used in a CT pancreas protocol may include a lower tube voltage (e.g. 80 kVp) and a higher contrast agent concentration (e.g. 400 mgI/mL) to optimize the visualization of the pancreas [(2,4,5)].
- The injection rate and dose of the contrast agent may also be adjusted to achieve the optimal enhancement of the pancreas 5.
Clinical Applications
- The CT pancreas protocol is commonly used to evaluate patients with suspected pancreatic cancer, pancreatitis, and other pancreatic disorders [(2,3,4,5,6)].
- The protocol can help to detect and characterize lesions in the pancreas, and to assess the extent of disease and potential treatment options [(2,3,4,5,6)].