View Large Image Figure ViewerDownload Hi-res image Download (PPT) Question: A 73-year-old man with a past medical history significant for hypertension and coronary artery disease presented with the complaint of a 50-lb weight loss over a period of 6 months. He also described symptoms of early satiety, nausea, and vomiting after solid foods, and had modified his diet to full liquids. There was no prior history of pancreatitis or peptic ulcer disease. His prior surgeries were a coronary artery bypass graft and an abdominal aortic aneurysm repair. His physical examination was normal, including a soft abdomen with a midline scar, with no tenderness, hernias, or palpable mass. His laboratory values were as follows: Na 138, K 3.8, Cl 103, CO2 31.8, Bun 9.0, Cr 0.9, Wbc 6.9, Hg 13.8, Hct 39.5, Plts 193, Tbili 0.8, Ast 18, Alt 16, Alb 3.5. An upper GI series (Figure A) confirmed a massively dilated duodenal bulb with a sudden tapering at the second portion of the duodenum. He underwent a computerized tomography (CT) scan of the abdomen (Figures B, C, D, and E) which demonstrated a markedly distended duodenum containing food debris, with a focal narrowing at the second portion of the duodenum. There was no evidence of bilary dilatation or a mass lesion. An EGD (Figure F) was subsequently performed, which showed a dilated proximal duodenum with a narrowing between D1 and D2, although the scope was able to pass beyond it. The duodenal mucosa proximal and distal to the narrowing appeared normal. The patient underwent an elective laparotomy. What is the diagnosis? Look on page 624 for the answer and see the Gastroenterology website (http://www.gastrojournal.org) for more information on submitting your favorite image to Image of the Month. At the time of laparotomy, an annular pancreas (Figure 7) was discovered upon careful examination of the duodenal transition point. A Roux-en-Y lateral duodenojejunostomy was performed. The patient recovered well and was discharged home tolerating a regular diet. It is unclear why the patient had such a late adult presentation of this congenital disorder, although one possibility is progressive stenosis at the site of the annulus. Annular pancreas is a rare congenital anomaly most often found in neonates and infants <1 year of age, and even less frequently in adults. The term was coined by Ecker in 1862 to describe the ringlike appearance due to a retained ventral pancreas encircling the duodenum. The incidence is difficult to assess, but in 1975 Ravitch and Woods described 3 cases per 20,000 autopsies. In adults, annular pancreas has multiple presentations including duodenal obstruction, pancreatitis, and common bile duct obstruction. Annular pancreas with periampullary malignancy has also been described. Prior to 1990, upper GI was the most commonly performed diagnostic procedure. The diagnosis is also possible with CT scan, as well as endoscopic retrograde cholangiopancreatography, magnetic resonance cholangiopancreatography, and endoscopic ultrasonography. However, in the absence of symptoms indicating the need for some of these studies, surgical diagnosis remains the gold standard and was required in up to 40% of cases reported by Urayama et al.3Urayama S. Kozarek R. Ball T. et al.Presentation and treatment of annular pancreas in an adult population.Am J Gastroenterol. 1995; 90: 995-999PubMed Google Scholar Treatment of annular pancreas is dictated by its presentation. Bypass procedures including duodenoduodenostomy, duodenojejunostomy, and gastrojejunostomy have been used to treat gastric outlet obstruction. Division of the ring of pancreatic tissue is contraindicated due to the high incidence of pancreatic and duodenal fistulas as well as underlying duodenal stenosis. Choledochojejunostomy, sphincterotomy, choledochostomy, and biliary stent have been performed to treat benign biliary obstruction, and pancreaticoduodenectomy is performed in the setting of associated malignancy.1Ravitch M.M. The pancreas in infants and adults.Surg Clin North Am. 1975; 55: 377-385PubMed Google Scholar, 2Khalid A. Slivka A. Approach to idiopathic recurrent pancreatitis.Gastrointest Endosc Clin N Am. 2003; 13: 695-716Abstract Full Text Full Text PDF PubMed Scopus (12) Google Scholar, 3Urayama S. Kozarek R. Ball T. et al.Presentation and treatment of annular pancreas in an adult population.Am J Gastroenterol. 1995; 90: 995-999PubMed Google Scholar