Initial investigation of choice in obstructive jaundice is
Transabdominal ultrasound scan is universally established as the most useful first line imaging study in the jaundiced adult.It provides an excellent evaluation of liver parenchyma & assessment of the presence/absence of bile duct dilatation. Reference:SRB's manual of surgery,5th edition,page no:656.
USG
ERCP
CT scan
PTC
G.I.T