Establishing the Clinical Utility of Glucagon-Enhanced MRCP for Improved Hepatopancreatobiliary Assessment

Background: Magnetic Resonance Cholangiopancreatography (MRCP) has continuously evolved to enhance visualization capabilities. However, diagnosing biliary ductal system pathology, particularly early primary sclerosing cholangitis (PSC), remains challenging. This study investigates the influence of intramuscular glucagon (IMG) administration on final image quality and pancreatobiliary ductal system diameter in MRCP. Methods: Forty patients (57.5% female; average age 34.45 ± 8.2) referred for Magnetic Resonance Enterography (MRE) underwent MRCP before and 8-12 min after IMG administration. Two independent MRI specialists analyzed Coronal T2-weighted fast spin-echo high-resolution 3D MRCP images quantitatively and qualitatively. Quantitative assessments involved measuring the transverse diameter of five specific biliary duct structures (inferior, mid, and upper common bile duct; right and left hepatic ducts) and three pancreatic duct segments (head, body, and tail). The qualitative evaluation used a five-point Likert-type scale (1 = perfect visualization; 5 = not visible) for the predefined segments. Interobserver variation was assessed using the Intraclass Correlation Coefficient (ICC). Results: Following IMG administration, the diameters of all corresponding biliary and pancreatic segments significantly increased, with consistently strong interobserver agreement demonstrated pre- and post-IMG administration. Moreover, in qualitative analysis, post-IMG administration scores indicated a significant decrease (p < 0.01) in visualization scores, signifying improved visualization at all corresponding points for both radiologists compared to the pre-glucagon administration scores. The ICC scores pre- and post-IMG administration demonstrated moderate to strong agreement. Conclusions: IMG administration improves MRCP imaging parameters by increasing ductal diameters and enhancing biliary tree visualization, underscoring its potential to detect subtle or early pathological changes.