Copyright @ Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. Computed Tomography Enteroclysis in the Diagnosis of Intestinal Diseases Gulgun Engin, MD Abstract: The role of computed tomography (CT) enteroclysis in the imaging of small bowel diseases is expanded with recent technolo- gical advances in multidetector CT system. Computed tomography enteroclysis is the examination of choice for patients with symptoms of intermittent small bowel obstruction, especially when there is a history of prior complex abdominal surgery, abdominal tumor, radiation therapy, and also in high grade obstructions with suspicion of extraintestinal internal fistula. Computed tomography enteroclysis is becoming the first-line modality for the evaluation of advanced and complicated small bowel Crohn disease. Computed tomography enteroclysis can also become an important complementary imaging technique to capsule endoscopy in the assessment of small bowel neoplasms and occult gastrointestinal hemorrhage. In this study, the technique and clinical applications of CT enteroclysis are reviewed; its advantages and limitations compared with the other imaging techniques and capsule endoscopy are discussed. Key Words: multidedector CT, CT enteroclysis, small bowel disease, diagnosis (J Comput Assist Tomogr 2008;32:9Y16) D espite the improvements of endoscopy systems, the small bowel is still the most difficult part of the gastrointestinal tract to investigate because of its length, diameter, and superposition of loops within the peritoneal cavity. Most of the limitations of barium follow-through examination have been overcome with enteroclysis. 1 However, computed tomography (CT) experiences have shown that enteroclysis fails to demonstrate important extraintestinal findings of the small bowel diseases. 2Y4 A comparison of barium enteroclysis with abdominal CT in small bowel Crohn disease (CD) has shown that the advantages of enteroclysis (demonstration of low-grade obstruction, sinus tracts, fistulae, and ulcerations) were the direct result of the volume challenge to the small bowel generated by the controlled infusion, whereas the advantages of CT were its capacity to demonstrate the transmural extent of inflammation and intraperitoneal or extraintestinal complications of the disease. 5 Computed tomography enteroclysis (CT-E) is an ima- ging modality of the small bowel that combines the advantages of conventional enteroclysis and multidetector row helical CT. 6 During the past 10 years, CT-E has evolved into an established modality for the investigation of various small bowel disorders. 6Y11 Recently, capsule endoscopy (CE) has been introduced as the main rival of CT-E. First results demonstrate CE to be superior to all imaging techniques in the diagnosis of small intestinal bleeding or tumor, and CD especially on early staged and nonstricturing recurrent forms. 12Y14 Although CE has several advantages to CT-E which include relatively low risk for the patient, absence of radiation, and minimal patient discomfort, it is not a perfect technique. Lesion localization and evaluation can be difficult with CE. The cost of the examination is also not fully reimbursed at this time. Another disadvantage of CE is that it is contraindicated in patients with known obstruction or stricture because the device could become lodged in the narrowed segment. 14 The role of CT-E in the imaging of small bowel diseases is expanded with recent technological advances in multidetector CT system and 3-dimensional reconstruction. Computed tomography enteroclysis with methylcellulose administered through a nasojejunal tube or peroral CT-E is becoming the first- line modality for the evaluation of suspected inflammatory bowel disease. These methods can also be important alternative or complementary imaging techniques to CE in the assessment of small bowel neoplasms. 7Y11,15,16 In this study, the technique and clinical applications of CT-E are reviewed; its advan- tages and limitations compared with the other imaging tech- niques and CE are discussed. TECHNIQUE Choice of Enteral Contrast Medium The intraluminal contrast medium can be used as negative (hypodense) (0.5% methylcellulose or pure water) or positive (hyperdense) (4%Y15% iodinated contrast medium or 1% barium suspension). 8 In our department, we prefer 0.5% methylcellulose suspension as a negative and 4% to 15% iodinated contrast medium as the positive contrast medium. As a negative contrast medium, pure water is inexpensive and readily available. However, it is suboptimal because it is absorbed by the intestinal mucosa. Therefore, pure water is relatively contraindicated in patients with renal and cardiac failure. Diluted barium solutions can be used as a positive contrast medium but contraindicated if there is any risk of leakage. 9 Negative luminal opacification with intravenous (IV) contrast medium is especially indicated in patients with unexplained subacute gastrointestinal bleeding. Intraluminal REVIEW ARTICLE J Comput Assist Tomogr & Volume 32, Number 1, January/February 2008 9 From the Department of Radiology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey. Received for publication October 18, 2006; accepted March 8, 2007. Reprints: Gulgun Engin, MD, Department of Radiology, Istanbul Faculty of Medicine, Istanbul University, Millet street, Capa 34390, Istanbul, Turkey (e-mail: gengin@istanbul.edu.tr; gulgunengin@hotmail.com). This work was supported by the Research Fund of the University of Istanbul (project number BYP-971/2006). Copyright * 2008 by Lippincott Williams & Wilkins