Endoscopic ultrasound in the diagnosis of chronic pancreatitis: a structured state-of-the-art review.

Abstract

Chronic pancreatitis (CP) is diagnosed by integrating clinical probability, structural imaging and, when required, pancreatic function. Endoscopic ultrasound (EUS) is proposed as a first-line investigation in selected patients evaluated in expert centers when the principal question is early or minimal-change CP in a high-probability clinical setting, or when a known focal pancreatic lesion requires detailed characterization or tissue acquisition. This proposed sequence is an individualized alternative to guidance recommending CT or MRI as initial imaging in the general population with suspected CP; cross-sectional imaging remains complementary for alternative diagnoses, complications and lesion staging. EUS also has an established role after inconclusive CT or MRI/MRCP. This structured state-of-the-art review addresses predefined clinical questions and separates established practice from adjunctive and investigational EUS technologies. Conventional B-mode EUS with standardized morphologic reporting is the established endoscopic technique, although interobserver variability and imperfect specificity limit its use as an isolated reference standard. Strain elastography, contrast-enhanced EUS and secretin-stimulated EUS pancreatic function testing can add stiffness, perfusion or functional information in selected patients. Shear wave elastography and detective flow imaging remain emerging technologies requiring multicenter validation and standardized thresholds. Tissue acquisition is not recommended solely to prove CP and should be reserved mainly for suspected malignancy or autoimmune pancreatitis. A stepwise pathway distinguishes selected first-line EUS assessment from the guideline-based CT/MRI-first sequence and integrates complementary imaging and selective functional testing.