Imaging Anatomy and Overview COMMON SYMPTONS AND SIGNS: IMAGING APPROACH AND DIFFERENTIAL DIAGNOSIS Abdominal Pain Nausea and Vomiting Small Bowel Obstruction and Ileus Diarrhea Constipation Gastrointestinal (GI) Bleeding Jaundice DISORDERS AFFECTING MULTIPLE ORGANS: IMAGING APPROACH Infectious, Inflammatory, and Degenerative Abdominal Abscesses and Fistulas HIV/AIDS IgG4-Related Disease Vasculitis Sarcoidosis Eosinophilic Gastroenteritis and Esophagitis Scleroderma and Related Disorders Cystic Fibrosis Trauma and Foreign Bodies Abdominal Trauma Foreign Bodies Barotrauma Neoplasms Leukemia and Lymphoma GI Stromal Tumors Neuroendocrine Tumors ABDOMINAL WALL AND PERITONEAL CAVITY: IMAGING APPROACH AND DIFFERENTIAL DIAGNOSIS Peritoneum, Mesentery, and Abdominal Wall: Imaging Approach and Differential DiagnosiS Infectious, Inflammatory, and Degenerative Peritonitis Ascites Inguinal Hernia Femoral Hernia Ventral Hernia Umbilical Hernia Obturator Hernia Spigelian Hernia Lumbar Hernia Paraduodenal Hernia Transmesenteric Hernia Bochdalek Hernia Morgagni Hernia Mesenteritis Benign Neoplasms and Tumor-Like Conditions Lymphangioma (Mesenteric Cyst) Desmoid Malignant Neoplasms Abdominal Mesothelioma Peritoneal Metastases and Lymphoma Pseudomyxoma Peritonei ESOPHAGUS: IMAGING APPROACH AND DIFFERENTIAL DIAGNOSIS Esophagus: Imaging Approach and Differential Diagnosis Infectious, Inflammatory, and Degenerative Candida Esophagitis Viral Esophagitis Chagas Disease Reflux Esophagitis Barrett Esophagus Caustic Esophagitis Drug-Induced Esophagitis Radiation Esophagitis Epidermolysis and Pemphigoid Esophageal Webs Schatzki Ring Cricopharyngeal Achalasia Achalasia Esophageal Motility Disturbances Zenker Diverticulum Pulsion Diverticulum Traction Diverticulum Intramural Pseudodiverticulosis Trauma Esophageal Perforation Boerhaave Syndrome Treatment Related Esophagectomy: Ivor Lewis and Other Procedures Fundoplication and Other Antireflux Procedures Benign Neoplasms and Tumor-Like Conditions Intramural Benign Esophageal Tumors Fibrovascular Polyp Esophageal Inflammatory Polyp Malignant Neoplasms Esophageal Carcinoma Esophageal Metastases and Lymphoma STOMACH AND DUODENUM: IMAGING APPROACH AND DIFFERENTIAL DIAGNOSIS Stomach: Imaging Approach and Differential Diagnosis Embryology and Anomalies Hypertrophic Pyloric Stenosis Duodenal Stenosis or Atresia Gastric Diverticulum Duodenal Diverticulum Infectious, Inflammatory, and Degenerative Gastritis and Duodenitis Duodenal Ulcer Gastric Ulcer Zollinger-Ellison Syndrome Ménétrier Disease Gastroparesis Gastric Bezoar Hiatal Hernia Gastric Volvulus Treatment Related Iatrogenic Injury: Feeding Tubes Partial Gastrectomy: Bilroth Procedures Imaging of Bariatric Surgery Benign Neoplasms and Tumor-Like Conditions Gastric Polyps Intramural Benign Gastric Tumors Malignant Neoplasms Gastric Carcinoma Gastric Metastases and Lymphoma SMALL INTESTINE: IMAGING APPROACH AND DIFFERENTIAL DIAGNOSIS Small Intestine: Imaging Approach and Differential Diagnosis Embryology and Anomalies Malrotation Duplication Cyst Meckel Diverticulum Infectious, Inflammatory, and Degenerative Small Bowel Diverticula Mesenteric Adenitis and Enteritis Opportunistic Intestinal Infections Intestinal Parasites and Infestation Celiac Sprue Disease Intestinal Lymphangiectasia Whipple Disease Mastocytosis Crohn Disease Intestinal (Angioneurotic) Angioedema Small Bowel NSAID Stricture Pneumatosis of the Intestine Bowel Ischemia Intussusception Gallstone Ileus Treatment Related Postoperative State, Bowel Radiation Enteritis and Colitis Small Intestine Transplantation Benign Neoplasms Hamartomatous Polyposis Syndromes Malignant Neoplasms Small Bowel Carcinoma Intestinal Metastases and Lymphoma COLON: IMAGING APPROACH AND DIFFERENTIAL DIAGNOSIS Colon: Imaging Approach and Differential Diagnosis Infectious, Inflammatory, and Degenerative Infectious Colitis Neutropenic Colitis (Typhlitis) Ulcerative Colitis Toxic Megacolon Ischemic Colitis Appendicitis Colonic Diverticulosis Epiploic Appendagitis Omental Infarct Sigmoid Volvulus Cecal Volvulus Colonic Ileus and Ogilvie Syndrome Trauma Colorectal Trauma Benign Neoplasms and Tumor-Like Conditions Colonic Polyps Villous Adenoma Malignant Neoplasms Colon Carcinoma Rectal Carcinoma Familial Polyposis and Gardner Syndrome Appendiceal Tumors Colonic Metastases and Lymphoma LIVER: IMAGING APPROACH AND DIFFERENTIAL DIAGNOSIS Liver: Imaging Approach and Differential Diagnosis Emryology and Anomalies Congenital Hepatic Fibrosis Hepatic AD Polycystic Kidney Disease Infectious, Inflammatory, and Degenerative Hepatic Pyogenic Abscess Hepatic TB and Fungal Infections Hepatic Amebic Abscess Hepatic Hydatid Cyst Hepatic Schistosomiasis Viral Hepatitis Alcoholic Liver Disease Autoimmune Hepatitis Steatosis and Steatohepatitis Hepatic Injury From Toxins Cirrhosis Nodular Regenerative Hyperplasia Regenerative and Dysplastic Nodules Glycogen Storage Disease Hemochromatosis (Iron Overload Disorders) Wilson Disease Vascular Disorders Arterioportal Shunt Portal Vein Occlusion Passive Hepatic Congestion Budd-Chiari Syndrome Venoocclusive Disease Hepatic Infarction Peliosis Hepatis Hereditary Hemorrhagic Telangiectasia Treatment Related Transjugular Intrahepatic Portosystemic Shunt (TIPS) Hepatic Transplantation Benign Neoplasms and Tumor-Like Conditions Hepatic Cyst Hepatic Cavernous Hemangioma Focal Nodular Hyperplasia Hepatic Adenoma Biliary Hamartomas Hepatic Angiomyolipoma and Lipoma Hepatic Inflammatory Pseudotumor Malignant Neoplasms Hepatocellular Carcinoma Fibrolamellar Carcinoma Peripheral (Intrahepatic) Cholangiocarcinoma Epithelioid Hemangioendothelioma Biliary Cystadenocarcinoma Hepatic Angiosarcoma Hepatic Metastases and Lymphoma BILIARY SYSTEM: IMAGING APPROACH AND DIFFERENTIAL DIAGNOSIS Biliary System: Imaging Approach and Differential Diagnosis Embryology and Anomalies Congenital Abnormalities of the Gallbladder Caroli Disease Choledochal Cyst Infectious, Inflammatory, and Degenerative Ascending Cholangitis Primary Sclerosing Cholangitis Recurrent Pyogenic Cholangitis Pancreatobiliary Parasites Gallstones and Sludge Gallbladder Hydrops and Empyema Gallbaldder Hydrops and Empyema Acute Calculous Cholecystitis Acalculous Cholecystitis Emphysematous Cholecystitis Xanthogranulomatous Cholecystitis Mirizzi Syndrome Hyperplastic Cholecystoses Porcelain Gallbladder Treatment Related Chemotherapy-Induced Cholangitis Benign Neoplasms and Tumor-Like Conditions Gallbladder Polyps Biliary Papillomatosis Malignant Neoplasms Gallbladder Carcinoma Cholangiocarcinoma Ampullary Carcinoma Biliary IPMN Biliary Metastases and Lymphoma PANCREAS: IMAGING APPROACH AND DIFFERENTIAL DIAGNOSIS Pancreas: Imaging Approach and Differential Diagnosis Embryology and Anomalies Agenesis of Dorsal Pancreas Annular Pancreas Pancreas Divisum Ectopic Pancreatic Tissue Infectious, Inflammatory, and Degenerative Acute Pancreatitis and Complications Chronic Pancreatitis Groove Pancreatitis Autoimmune (IgG4) Pancreatitis Treatment Related Postoperative Pancreas Pancreatic Transplantation Benign Neoplasms and Tumor-Like Conditions Nonneoplastic Pancreatic Cysts Pancreatic Serous Cystadenoma Malignant Pancreatic Neoplasms Pancreatic Ductal Carcinoma Mucinous Cystic Pancreatic Tumor Pancreatic IPMN Pancreatic Solid and Pseudopapillary Epithelial Neoplasm Pancreatic Metastases and Lymphoma Atypical and Rare Pancre.