Purely for diagnostic purpose preferred mode of visualizing biliary tree will be

MAGNETIC RESONANCE CHOLANGIO PANCREATOGRAPHY (MRCP) It is a non-invasive diagnostic method using magnetic field and energy as resonance. *T1 weighted images are used for pancreas. *T2 weighted images are used for biliary tree. (Both images are used to see invasion and adjacent structures.) Advantages * It is non-invasive. * It gives equal or better imaging than ERCP. *Pancreatic divisum or annular pancreas are identified easily by MRCP. * Ductal dilatation in chronic pancreatitis and visualization of duct beyond stricture is possible. * Islet tumours are better visualized and diagnosed by MRCP. Disadvantages * Availability. * It is only diagnostic. Not therapeutic (ERCP is both diagnostic as well as therapeutic). * Costly.Magnetic Resonance Cholangiopancreatography(MRCP) is a non-contrast non-invasive imaging method,better than ERCP as diagnostic tool in biliary and pancreatic diseases. Reference:SRB&;s manual of surgery,5th edition,page no:613