Will cholecystitis be visible on Magnetic Resonance Cholangiopancreatography (MRCP)?

From the Guidelines

Cholecystitis can be detected on MRCP, with a sensitivity of 85% and specificity of 81%, making it a reliable alternative to other imaging tests, especially in cases where ultrasound is equivocal or difficult to perform. According to the study by Kiewiet et al 1, MRI, which often includes MRCP, has excellent accuracy for visualization of normal and dilated bile ducts and detection of stone disease compared to noncontrast CT. MRCP can detect signs of gallbladder inflammation, including gallbladder wall thickening, pericholecystic fluid, and gallbladder distention, as well as identify gallstones, which are often the cause of cholecystitis.

Some of the key advantages of using MRCP to detect cholecystitis include:

• Excellent accuracy for visualization of normal and dilated bile ducts and detection of stone disease
• Ability to detect gallbladder wall edema and pericholecystic fluid, which are signs of gallbladder inflammation
• Non-invasive and does not use ionizing radiation, making it a useful alternative to CT scans
• Can be particularly helpful in patients who are difficult to examine with ultrasound, such as those with severe abdominal tenderness or gas in the bowel that interferes with the ultrasound signal.

However, it's worth noting that MRCP is not typically the first-line imaging test for suspected cholecystitis, and ultrasound is usually performed first due to its availability, lower cost, and high accuracy for detecting gallbladder inflammation 1. If cholecystitis is suspected clinically, the diagnostic workup would typically include laboratory tests and an ultrasound before proceeding to MRCP.

From the Research

Diagnostic Role of MRCP in Cholecystitis

• MRCP can be used to diagnose acute cholecystitis and its related complications, such as mural necrosis, perforation, and abscess formation 2.
• The imaging findings consistent with uncomplicated cholecystitis include gallbladder distension, intraluminal sludge and gallstones, impacted stones obstructing the gallbladder neck or cystic duct, thickening of the gallbladder wall, abnormal signal intensity and edematous stratification, and pericholecystic and perihepatic fluid 2.
• MRCP allows prompt detection and comprehensive visualization and characterization of cholecystitis-related complications 2.

Sensitivity and Specificity of MRCP

• The sensitivity and specificity of MRCP in detecting choledocholithiasis in acute cholecystitis were found to be 76.2-85.7% and 84.3-92.2%, respectively 3.
• MRCP yields a high negative predictive value regarding the detection of choledocholithiasis, making it a useful tool for ruling out choledocholithiasis in patients with acute cholecystitis 3.
• The overall sensitivity, specificity, positive predictive value, and negative predictive value of MRCP in diagnosing acute cholecystitis were found to be 100%, 66.6%, 94.4%, and 100%, respectively 4.

Clinical Applications of MRCP

• MRCP can be used as a preoperative evaluation tool for acute cholecystitis, providing useful information for planning treatment 5, 6.
• MRCP can help identify patients with choledocholithiasis, reducing the risk of misdiagnosis and overlooked choledocholithiasis 5.
• The use of MRCP in the emergency setting can facilitate prompt and efficient triage of patients with suspected cholecystitis and inconclusive clinical, laboratory, and sonographic findings 2.