<prompt> The initial investigation of choice for a post cholecystectomy biliary stricture isUltrasound guided aspirationERCP and stentingComputed tomographyMagnetic resonance imaging  <response>: Computed Tomography CT is probably the best initial study, the results which help direct fuher investigations A good quality CT scan shows a dilated biliary tree and helps localise the level of ductal obstruction in patients with strictures CT identities fluid collections or ascites, which may suggest the possibility of vascular damage Other Radiological investigations in post cholecystectomy bile duct injury Duplex ultrasonography Percutaneous transhepatic cholangiography Magnetic resonance cholangiopancreatography. ERCP Isotopic scanning techniques Aretriography and delayed phase poography Ref: Blumga 5th edition Pgno :627 