Pancreatic trauma

MRI diagnosis of trauma consequences

Magnetic resonance imaging is a key tool for evaluating pancreatic injuries resulting from direct blunt abdominal trauma. On non-contrast T1- and T2-weighted images (WI), a hematoma is visualized within the organ parenchyma as a hyperintense signal.

For a more detailed assessment, gadolinium-enhanced MRI is used. This method clearly identifies a major parenchymal defect caused by a fracture (fracture) or rupture of the gland.

Special attention during diagnostic imaging is paid to the state of the ductal system. Trauma may result in rupture of the main pancreatic duct. Such an injury naturally leads to a specific complication — disconnected duct syndrome (disconnected duct syndrome), which requires timely detection to determine further patient management.

Pancreatic biopsy

Morphological verification of pancreatic alterations requires a biopsy. The use of modern 18-G needles allows for safe passage through soft tissues, ensuring a low risk of complications (morbidity). The overall sensitivity of pancreatic biopsy is estimated to be high, ranging from 78% to 99%.

Depending on the purpose of the study, two main types of biopsy are used:

• Core needle biopsy (Cutting needles): performed using 16–18 G needles. This is the preferred method for investigating space-occupying lesions, as it yields a complete tissue core for precise histological examination.
• Fine-needle aspiration biopsy (FNAB / FNAB): used to collect a cellular aspirate for subsequent cytological analysis.

Diagnosis of cystic lesions deserves special mention. Performing fluid FNAB (usually percutaneously under ultrasound guidance) is recognized as the most reliable method for differentiating between pseudocysts, serous, and mucinous cystic neoplasms.

Post-biopsy complications

Despite the minimally invasive nature of the procedure, biopsy carries a risk of adverse events:

• Mild to moderate complications: observed in approximately 15% of cases. Most commonly manifested as abdominal pain after the procedure is completed.
• Post-procedure pancreatitis: a specific complication occurring in 3% of patients.
• Rare and severe complications: these include massive hemorrhage and the extremely rare implantation metastasis of malignant cells along the needle tract (needle-track seeding).

Drainage of fluid collections

Fluid collections in the pancreatic and peripancreatic tissue, most commonly developing secondary to acute pancreatitis, respond well to percutaneous drainage.

There are two main indications for this procedure:

1. The need to obtain material to test for infection.
2. Drainage of a confirmed abscess or a definitively infected collection.

Algorithm for suspected infection: if a patient with acute pancreatitis develops a fever, ultrasound- or CT-guided FNAB is indicated. Several milliliters of fluid are aspirated for immediate microbiological analysis. If infection is confirmed, placement of a percutaneous drainage catheter is performed in the same session.

Abscess management features: the contents of infected foci are usually highly viscous. Therefore, large-diameter catheters (12 F or larger) are used to ensure adequate drainage. To achieve optimal results (up to 86% success rate), separate drainage of multiple abscesses using additional large catheters under strict fluoroscopic control may be required.

Important limitation: percutaneous drainage is not recommended for liquefied pancreatic necrosis — so-called walled-off necrosis (walled-off necrosis, WON).

Class and exam questions

What else to study on this topic

• MR cholangiopancreatography in the evaluation of the ductal system
• Cytological features of serous and mucinous cystic neoplasms
• Management tactics for patients with walled-off pancreatic necrosis (WON)
• Prevention of post-procedure pancreatitis

Other topics in the section "Diagnostic Radiology of the Abdominal Organs"

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.