E5202. The Alphabet According to the Duodenum: Pathologies from A to Z - Part I
  1. Yashant Aswani; University of Iowa Hospitals & Clinics
  2. Karan Rao; University of Iowa Hospitals & Clinics
  3. Sarah Averill; University of Iowa Hospitals & Clinics
  4. Malak Itani; Mallinckrodt Institute of Radiology
  5. Rostislav Ranguelov; University of Iowa Hospitals & Clinics
  6. Mason Vaillancourt; University of Iowa Hospitals & Clinics
  7. Mohammad Ansari; University of Iowa Hospitals & Clinics
Relative to the other intraabdominal organs such as the liver, gallbladder, spleen, stomach, and colon, fewer literature articles and abstracts comprehensively describe imaging pathology of the duodenum.

Educational Goals / Teaching Points
The goal of this online educational exhibit is to highlight duodenal pathologies, across multiple imaging modalities such as CT, MRI, ultrasound, fluoroscopy, and MR cholangiopancreatography. In this part 1 of the exhibit, we present duodenal pathologies starting with letters A–M that cover developmental, inflammatory, infectious, traumatic, and neoplastic pathology. After reviewing this exhibit, radiologists and those in training will be able to describe embryology of the duodenum; discuss normal imaging appearance of the duodenum; understand pathophysiology and clinical significance of duodenal pathologies starting with letters A–M; and recognize key imaging findings of duodenal pathologies across multiple imaging modalities.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Embryology of duodenum. Normal imaging appearance of duodenum. Pathologies in duodenum A = Annular pancreas (complete and partial), angioedema (hereditary and acquired), afferent loop syndrome, atresia, amyloid. B = Bouveret syndrome. C = Choledochocele. D = Diverticulum and its complications (diverticulitis, perforation, bleeding, and Lemmel’s syndrome), duplication cyst. E = ERCP-related duodenal injuries. F = Fistula (primary and secondary aortoduodenal, inflammatory and malignant cholecystoduodenal, coloduodenal, duodenum-pseudocyst), foreign bodies (safety pin, wrapper, IVC filter, pen, passed gall stone, bezoar). G = Groove pancreatitis. H = Hematoma (Henoch-Schonlein Purpura, hemophilia, bleeding ulcers). I = Intussusception, infectious (Giardia, H. pylori, MAC) and inflammatory disorders (pancreatitis, immune check point inhibitor mediated, celiac disease, Crohn’s disease, coexistent celiac and Crohn’s, coexistent celiac and ulcerative colitis), inversum. J = Juvenile polyposis. K = Kartagener’s syndrome. L = Lipoma and lipomatosis. M = Malrotation spectrum.

Radiologists should be familiar with the broad range of conditions that can affect the duodenum, an often-overlooked segment of the bowel. This educational exhibit aims to highlight multimodality imaging for recognition of duodenal pathologies. Recognizing and understanding duodenal pathologies will improve patient diagnoses and management.