You are in: eMedicine Specialties > Radiology > GASTROINTESTINAL Duodenum, UlcersArticle Last Updated: Dec 20, 2006AUTHOR AND EDITOR INFORMATIONSection 1 of 9
  Author: Isaac Hassan, MB, ChB, FRCR, DMRD, Former Senior Consultant Radiologist, Department of Radiology, St Bernard's Hospital, Gibraltar Isaac Hassan is a member of the following medical societies: American Roentgen Ray Society and Royal College of Radiologists Editors: Bernard D Coombs, MB, ChB, PhD, Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand; David Andrew Nicholson, BM, BS, FRCR, Honorary Lecturer, Department of Radiology, University of Manchester; Consultant Gastrointestinal Radiologist, Department of Radiology, Hope Hospital, Salford Royal Hospital NHS Trust; Robert M Krasny, MD, Consulting Staff, Department of Radiology, The Angeles Clinic and Research Institute; Eugene C Lin, MD, Consulting Staff, Department of Radiology, Virginia Mason Medical Center Author and Editor Disclosure Synonyms and related keywords: DU, peptic ulcer, gastric ulcer, Helicobacter pylori, H pylori, Zollinger-Ellison syndrome INTRODUCTIONSection 2 of 9
  BackgroundDuodenal ulcers (DUs) affect nearly 10% of the adult population at some time (Levine, 2000). DUs account for two thirds of all peptic ulcers, which are defined as mucosal breaks >3 mm, and gastric ulcers account for the rest. Unlike gastric ulcers, which may be malignant in about 5% of cases (Levine, 2000), DUs are almost invariably benign; therefore, treatment with antisecretory drugs can be commenced after radiologic diagnosis, without endoscopy being performed beforehand. PathophysiologyThe most common cause of DUs is infection with Helicobacter pylori (Pattison et al, 1997; Peek and Blaser, 1997; Suerbaum and Michetti, 2002). About 90% of DUs and 70-75% of gastric ulcers are associated with H pylori infection. The second most common cause of DUs is the use of nonsteroidal anti-inflammatory drugs (NSAIDs), which account for most H pylori–negative ulcers (Lanas et al, 1997). Severe physiologic stress (eg, burns, surgery, head injury) may induce peptic ulceration. Other causes are relatively rare and include gastrinoma (ie, Zollinger-Ellison syndrome) and radiation- or chemotherapy-induced ulcers. Several diseases are associated with an increased risk of peptic ulceration; these include cirrhosis, chronic pulmonary disease, renal failure, and renal transplantation. FrequencyUnited StatesAbout 4.5 million people are affected annually, and approximately 10% of the population has evidence of a DU at some time (Levine, 2000). The prevalence of DU is estimated to be 6-15% in the general population; this is linked to the presence of H pylori. In those infected with H pylori, the lifetime prevalence is approximately 20% (Levine, 2000). Overall, the incidence of DU has been decreasing over the past 3-4 decades. InternationalThe frequency rates of DUs in other countries are variable and are determined primarily by association with their major causes: H pylori infection and NSAID use. Mortality/MorbidityDU causes significant morbidity related to pain. Hospitalization is required mainly for complications such as ulcer hemorrhage, perforation, penetration, and obstruction. The annual rate of any complication in patients of all age groups is approximately 1-2% per ulcer (Levine, 2000). The mortality rate associated with ulcer hemorrhage has remained about 5% over the past 20 years, despite advances in medical therapy. However, in patients who require surgical intervention for complications, such as perforation and obstruction, the mortality rate is significantly higher in the elderly than in other age groups. SexThe prevalence has shifted from a male predominance to similar occurrences in males and females. The lifetime prevalence is approximately 11-14% for men and approximately 8-11% for women (Levine, 2000). AgeDU rates in younger men are decreasing, but they are increasing in older women. These trends reflect the prevalence of H pylori infection and the use of NSAIDs in older populations. AnatomyThe duodenum consists of 4 parts. The duodenal bulb, or cap, and the pars superior make up the first part. The second part consists of the descending duodenum, where the duodenal papilla and ampulla of Vater are located. The ampulla of Vater contains the outlet of the conjoined or separate pancreatic and bile ducts. The third part consists of the horizontal duodenum and extends from the second part to the arteriomesenteric bundle, where the superior mesenteric artery crosses anterior to the duodenum. The fourth, or ascending, part extends from this point to the duodenojejunal flexure. Clinical DetailsThe patient's history may include the following features:
Physical examination findings may include the following:
Preferred Examination
Limitations of TechniquesEndoscopy with biopsy has a sensitivity of as high as 95%, but small ulcers in the base of the duodenal bulb may be missed. In the presence of gastric outlet or proximal duodenal obstruction, the endoscope may be unable to pass through the stenosis, and the full extent and cause of the obstruction may not be defined. Single-contrast barium studies may cause as many as 40% of small ulcers to be missed, but double-contrast barium images depict as many as 95% of ulcers larger than 10 mm (Levine, 2000); these results are comparable to those of endoscopy . However, the sensitivity of double-contrast barium examination decreases with smaller ulcers and recurrent ulcers in a deformed duodenal bulb; therefore, it is not reliable in the detection of duodenitis or duodenal erosions. Barium studies have a disadvantage because biopsy specimens cannot be obtained to test for H pylori infection or to evaluate a suspicious lesion. DIFFERENTIALSSection 3 of 9
Cholecystitis, Acalculous Cholecystitis, Acute Cholelithiasis Crohn Disease Gastric Ulcer Gastroesophageal Reflux Gastrointestinal Bleeding, Upper Pancreatitis, Acute Pancreatitis, Chronic Tuberculosis, Gastrointestinal Zollinger-Ellison Syndrome RADIOGRAPHSection 4 of 9
FindingsMost DUs are depicted as round or ovoid pools of barium. About 5% may be linear. Most are smaller than 1 cm in diameter. Giant DUs, defined as those > 2 cm in diameter, have an increased risk of perforation, obstruction, and bleeding. Multiple ulcers occur in about 15% of patients (Levine, 2000); Zollinger-Ellison syndrome should be considered in these patients. About 95% of DUs occur in the duodenal bulb (Levine, 2000), and the rest occur in the postbulbar duodenum, which consists of the proximal 2 cm of the descending duodenum above the ampulla of Vater. As many as half of all DUs occur in the anterior wall of the bulb. Technique of double-contrast barium study Biphasic examination combines the advantages of the double-contrast views of the duodenum using high-density barium with the advantages of the prone or erect compression views using low-density barium to show ulcers in the anterior wall of the bulb. Intravenous (IV) glucagon 0.1 mg and effervescent granules are administered as part of the double-contrast examination, which is followed by the acquisition of single-contrast compression views with low-density barium. Bulbar ulcers Bulbar ulcer craters are depicted as well-defined round or ovoid pools of barium that can be seen en face or in profile (see Images 1-5); they are often surrounded by a smooth mound of edematous mucosa. Radiating folds converge to the edge of the crater (see Image 3). Ulcers in the anterior wall may be detected as a ring shadow (see Image 4), with barium coating the edge of the unfilled ulcer crater. These craters are filled on prone or erect compression views. The duodenal bulb is often deformed by edema and spasm associated with the ulcer or by scarring from a previous ulcer (see Images 6-7). Small ulcers may not be detected in a deformed bulb. Postbulbar ulcers Postbulbar ulcers are usually located in the medial wall of the proximal descending duodenum above the ampulla of Vater (see Images 8-9) and are prone to bleeding. Detection of the ulcer niche or crater is often difficult because of the associated edema and spasm, which may also cause indentation of the lateral wall of the descending duodenum opposite the ulcer. This indentation may lead to stricture formation as a result of fibrosis and may mimic a carcinoma of the duodenum. Ulcer healing Healing is often rapid, with a decrease in the size of the ulcer and a change from a round to a linear configuration. Healing may lead to scarring, with radiating mucosal folds converging to the site of the previous ulcer. Bulbar deformity results from asymmetrical scarring and retraction during healing (see Images 6-7). Pseudodiverticula result from the expansion of normal segments of the cap between areas of fibrosis. If present, the typical cloverleaf appearance of the scarred bulb is caused by multiple pseudodiverticula formation. Complications of duodenal ulceration
Degree of ConfidenceSingle-contrast barium studies may cause as many as 40% of small ulcers to be missed, but double-contrast barium images depict as many as 95% of ulcers larger than 10 mm; these results are comparable to those of endoscopy. However, the sensitivity of double-contrast barium examination decreases with smaller ulcers and recurrent ulcers in a deformed duodenal bulb. Double-contrast barium examination is not reliable in the detection of duodenitis or duodenal erosions. False Positives/NegativesUlcers may be obscured by edema, spasm, or scarring. False-positive results are caused by pseudodiverticula and small pools of barium in a deformed bulb resulting from previous peptic ulceration. CT SCANSection 5 of 9
FindingsCT scanning has little role in the primary detection of DUs. However, primary inflammatory processes of the duodenum, such as ulcers, duodenitis, and secondary involvement from pancreatitis, can reliably be diagnosed with CT scanning (Horton and Fishman, Crit Rev Comput Tomogr, 2004). Careful CT scanning technique and three-dimensional imaging can help optimize detection of abnormalities and disease, as well as help with surgical planning. They include the use of oral contrast, preferably water, as well as IV contrast. CT scanning also has a role in the detection of subphrenic and other collections that may occur after perforation of a DU (see Image 15). ULTRASOUNDSection 6 of 9
FindingsUltrasonography may indicate the presence of a giant DU. Its main role is in the detection of other causes of upper abdominal pain such as that caused by gallstones and pancreatitis. This modality also depicts subphrenic and other collections resulting from a perforated DU. INTERVENTIONSection 7 of 9
Transcatheter embolization may be used to treat bleeding DUs. Terminal muscular-branch vessel embolization is more effective than gastroduodenal artery embolization in the initial and long-term control of bleeding. Terminal vessels may be occluded with 6-cyanoacrylate, but duodenal stenosis is a late complication in one quarter of all patients. Fluoroscopically guided balloon (15 or 20 mm in diameter) dilatation may be used for benign duodenal strictures caused by peptic ulcers, Crohn disease, or postoperative adhesion (Kim et al, 2005). Duodenal perforation may occur, necessitating emergency surgery. Medical/Legal Pitfalls
MULTIMEDIASection 8 of 9
REFERENCESSection 9 of 9
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