Is a computed tomography (CT) scan of the abdomen with contrast indicated for diagnosing pancreatitis?

From the Guidelines

A computed tomography (CT) scan of the abdomen with contrast is indicated for diagnosing pancreatitis, especially when the diagnosis is uncertain or complications are suspected, as it provides valuable information on the severity of the disease and potential complications, such as necrosis, pseudocysts, and vascular complications. According to the 2019 WSES guidelines for the management of severe acute pancreatitis 1, CT is not required in the majority of patients with acute pancreatitis, but it is useful in certain situations, such as when the diagnosis is uncertain or when complications are suspected. The use of contrast-enhanced CT (CECT) can help detect necrotic areas and provide an early overall detection rate of 90% with close to 100% sensitivity after 4 days for pancreatic necrosis 1.

Key Points to Consider

• The optimal timing for CT is usually 72-96 hours after symptom onset, as earlier imaging may underestimate the severity of pancreatitis 1.
• CECT is the imaging modality of choice for diagnosis, staging, and detection of complications of acute pancreatitis, and has major roles in the evaluation of patients with known or suspected acute pancreatitis 1.
• The CT severity index, established by Balthazar et al. 1, can be used to grade the severity of pancreatitis based on the degree of inflammation, presence of fluid collections, and extent of necrosis.
• MRI is preferable to CECT in patients with allergy to iodinated contrast, in patients with renal impairment/insufficiency, in young or pregnant patients to minimize radiation exposure 1.
• CT without contrast is an alternative for patients with severe contrast allergies or significant kidney dysfunction, though it provides less diagnostic information 1.

Special Considerations

• Patients with kidney problems, contrast allergies, or those taking metformin may require special preparation, including hydration or temporary medication discontinuation 1.
• The contrast allows radiologists to assess pancreatic enhancement patterns, which helps differentiate viable from non-viable pancreatic tissue 1.
• In some cases, oral contrast may also be administered to better visualize the gastrointestinal tract 1.

From the FDA Drug Label

OMNIPAQUE diluted to concentrations from 6 mg Iodine/mL to 9 mg Iodine/mL administered orally in conjunction with OMNIPAQUE 300 at a concentration of 300 mg Iodine/mL administered intravenously is indicated in adults for contrast enhanced computed tomography of the abdomen. OMNIPAQUE diluted to concentrations from 9 mg Iodine/mL to 21 mg Iodine/mL administered orally in conjunction with OMNIPAQUE 300 at a concentration of 300 mg Iodine/mL administered intravenously are indicated in pediatric patients for use in contrast enhanced computed tomography of the abdomen.

The use of a computed tomography (CT) scan of the abdomen with contrast is indicated for diagnosing conditions in the abdomen, but the label does not specifically mention pancreatitis as an indication. However, since the label mentions that the contrast is indicated for contrast enhanced computed tomography of the abdomen, it can be inferred that a CT scan of the abdomen with contrast may be useful in diagnosing pancreatitis, which is a condition affecting the abdomen.

• Key points:
  • The label indicates the use of contrast for CT scans of the abdomen.
  • The label does not specifically mention pancreatitis.
  • A CT scan with contrast may be useful in diagnosing abdominal conditions, including potentially pancreatitis. 2

From the Research

Indications for CT Scan with Contrast in Diagnosing Pancreatitis

• A computed tomography (CT) scan of the abdomen with contrast is indicated for diagnosing pancreatitis, as it can accurately diagnose and stage the disease 3, 4, 5.
• Contrast-enhanced CT is preferred for patients with acute pancreatitis because it provides the necessary information for percutaneous management 3.
• CT scans are highly accurate and sensitive in both diagnosing and demonstrating the extent of pancreatitis, making them the imaging method of choice for assessing the extent of acute pancreatitis and evaluating complications 6.

Advantages of CT Scan with Contrast

• CT scans with contrast can detect serious complications that are often clinically unsuspected, such as pancreatic necrosis and extrapancreatic phlegmonous collections 5.
• CT severity indices, such as the CT severity index (CSI) and modified CSI (MCSI), can be used to predict the severity and clinical outcome of acute pancreatitis 6, 7.
• MCSI has been shown to be a more accurate predictor of severity, clinical outcome, and mortality compared to CSI and Ranson's criteria 7.

Limitations and Considerations

• Some studies suggest a detrimental effect of intravenous iodinated contrast agents in acute pancreatitis, but the positive advantages of enhanced CT outweigh the possible risks 4.
• CT scans may not be as effective in detecting the earliest changes of chronic pancreatitis, for which other diagnostic methods such as ERCP and tests of pancreatic function may be more sensitive 4.