<prompt> Investigation of choice in cholelithiasis is -MRIX-rayCTUSG  <response>: Ans. is d i.e., USG Investigations of choice in GITo Investigation of choice for esophageal motility disorders Achalasia, , Diffuse esophageal spasm Esophageal atresia, nutcracker esophagus - Manometryo Best diagnosis of Barrets esophagus - Endoscopy and biopsy,o Investigation of choice for gastroesophageal reflux disease - Endoscopyo Best investigation for documenting episode of GERD - pH and radionuclide study,o Investigation of choice for esophageal carcinoma - Esophageoscopy endoscopyo Investigation of choice for small bowrel tumor - Small bowel enema Barium follow througho Gastrointestinal contrast medium of choice including small bowel enema - Barium sulfateo Substance used for OCG - lopanoic acido Investigation of choice for gall stone and obstructive jaundice - USGo Investigation of choice for acute cholecystitis - Transabdominal USGo Best most accurate investigation for acute cholecvstis - Radionuclide scano Investigation of choice for acute cholangititis - Transabdominal USGo Investigation of choice for acute pancreatitis - CECTo Investigation of choice for chronic pancreatitis - ERCPo Investigation of choice for pancreatic carcinoma - CECTo Investigation of choice to detect minimal ascites - USGo Most sensitive investigation for Carolis disease - Cholangiography.o Investigation of choice for upper abdominal trauma - CT scano Investigation of choice for diagnosis and staging of GIST - CT scan.o Investigation of choice for assessment of treatment response and recurrence of GIST - PET preferably in combination with CTo Intitial most important imaging modality in cases of acute abdomen due to intestinal obstruction and perforation - Plain x-ray.o Screening modality of choice when acute abdomen is suspected to be of biliary origin - USG.o Investigation of choice for acute abdomen especially those suffering from pancreatitis and intrabdominal abscess - CT scan.. 