Intest Res.  2015 Jan;13(1):27-38. 10.5217/ir.2015.13.1.27.

Computed Tomography Enterography and Magnetic Resonance Enterography in the Diagnosis of Crohn's Disease

• Kim SH

• KMID: 1807374
• DOI: http://doi.org/10.5217/ir.2015.13.1.27

Abstract

Imaging of the small bowel is complicated by its length and its overlapping loops. Recently, however, the development of crosssectional imaging techniques, such as computed tomography enterography (CTE) and magnetic resonance enterography (MRE) has shifted fundamental paradigms in the diagnosis and management of patients with suspected or known Crohn's disease (CD). CTE and MRE are noninvasive imaging tests that involve the use of intraluminal oral and intravenous contrast agents to evaluate the small bowel. Here, we review recent advances in each cross-sectional imaging modality, their advantages and disadvantages, and their diagnostic performances in the evaluation of small bowel lesions in CD.

Keyword

Tomography, spiral computed; Magnetic resonance imaging; Inflammatory bowel diseases; Crohn disease

MeSH Terms

Contrast Media
Crohn Disease*
Diagnosis*
Humans
Inflammatory Bowel Diseases
Magnetic Resonance Imaging
Tomography, Spiral Computed
Contrast Media

Figure

• 

  Fig. 1 Coronal CT enterography images using different types of neutral enteric contrast agents. CT enterography using polyethylene glycol (middle) and sorbitol (right) distends the small bowel effectively, while CT enterography using water (left) distends the small-bowel loops suboptimally.

• 

  Fig. 2 An axial CT enterography image using diluted gastrografin as a positive enteric contrast agent. Marked bowel wall thickenings (arrows) are present at the distal ileum. However, mucosal enhancement is completely obscured by the high-attenuation intraluminal positive contrast agent (*).

• 

  Fig. 3 CT enteroclysis. A coronal CT enteroclysis image with the marked and uniform distension of entire small-bowel loops, including the jejunum (*) and the ileum (•). Note the nasojejunal catheter inserted in the stomach (arrow) and the duodenum (arrowhead).

• 

  Fig. 4 Three-dimensional reconstruction CT images of the small bowel. (A) Sagittal multiplanar reconstruction CT images demonstrate wall thickening with luminal narrowing (arrows) with fibrofatty proliferation (*) in the descending colon of a patient with CD. (B) Arterial phase, maximum intensity projection images in different patients depict the marked engorgement of the mesenteric vessels (comb sign) (*) supplying the involved bowel segment. (C) A transparent volume-rendering CT enteroclysis image using air as a negative contrast agent clearly demonstrates longitudinal ulceration and shortening (arrows) on the mesenteric border of the ileum, and pseudosacculation (arrowheads) on the anti-mesenteric border. (D) A virtual enteroscopy image from the same patient also shows longitudinal ulceration and a fold deformity (arrows) in the ileum.

• 

  Fig. 5 Low-dose CT enterography images obtained using 100 kVp and 150 mAs in a 17-year-old boy with suspected CD. (A) An enteric phase CT image reconstructed using the conventional filtered back projection algorithm, had suboptimal image quality at the pelvic cavity because of severe noise. (B) However, the CT image reconstructed using an iterative reconstruction algorithm demonstrates a dramatic reduction in image noise, and shows multifocal enhancing wall thickening (arrows) in the distal ileum. The patient was diagnosed with CD on the basis of colonoscopic biopsy.

• 

  Fig. 6 A 15-year-old boy with CD and elevated inflammatory markers. (A-C) Magnetic resonance enterography images using (A) true fast imaging with steady-state precession (TrueFISP) (B) half-Fourier acquisition single-shot turbo spin-echo (HASTE), and (C) postcontrast T1-weighted 3-dimensional spoiled gradient recalled (SPGR) fat-saturated sequences show marked and asymmetric ileal wall thickening (arrows). Note the marked engorgement of the adjacent mesenteric vessels (comb sign) (*) on the TrueFISP sequence (A) and marked enhancement on the postcontrast T1-weighted sequence (C), indicating active inflammation.

• 

  Fig. 7 A 15-year-old boy with CD. (A) Axial half-Fourier acquisition single-shot turbo spin-echo (HASTE) and (B) postcontrast T1-weighted magnetic resonance enterography images show marked distal ileal circumferential wall thickening with strong transmural hyperenhancement (arrowheads), consistent with active inflammation. (C) Axial diffusion-weighted image demonstrates the high signal intensity (arrowheads) associated with the involved ileum, suggesting the restricted diffusion of water within the distal ileum because of active inflammation.

• 

  Fig. 8 CT findings of active inflammation in CD. (A) An axial CT image shows bowel wall thickening (arrows) with bilaminar mural stratification and mucosal hyperenhancement. (B) A coronal CT image of a different patient demonstrates trilaminar mural stratification (arrows) with mucosal and serosal hyperenhancement. Note the dilated vasa recta (*) or comb sign in the mesentery, A B indicating active disease.

• 

  Fig. 9 Chronic CD with submucosal fat deposits (arrows) in several small bowel loops.

• 

  Fig. 10 Reversible and irreversible strictures in CD. (A) A reversible stricture. The axial CT image demonstrates the narrowing of the bowel lumen caused by bowel wall edema with mural hyperenhancement and mural stratification (arrows), indicating that the stricture is not yet fibrotic. (B) An irreversible stricture. The axial CT image shows an abrupt luminal narrowing of the jejunum (arrows) with homogeneous and weak enhancement. The patient underwent jejunal segmental resection, and final histopathology confirmed chronic fibrotic strictures associated with CD (not shown).

• 

  Fig. 11 A 38-year-old man with CD. The axial CT image clearly depicts an enteroenteric fistula (arrow) in the right lower quadrant area.

• 

  Fig. 12 Fibrofatty proliferation in a 26-year-old man with active CD. The axial CT image shows a marked proliferation of fat (*) at the medial aspect of the inflamed ascending colon (A). Note the paucity of fat around the normal descending colon (D).

• 

  Fig. 13 An anal fistula and perianal abscess in a 27-year-old man with CD. (A) An axial CT image shows a large perianal abscess (*) just next to the anus (a). However, the anal fistula itself is not apparent on the CT image. (B) In contrast, serial T2-weighted magnetic resonance images clearly depict an anal fistula itself (arrows), which connects the anal lumen (a) and perianal abscess (*).

Reference

1. Raptopoulos V, Schwartz RK, McNicholas MM, Movson J, Pearlman J, Joffe N. Multiplanar helical CT enterography in patients with Crohn's disease. AJR Am J Roentgenol. 1997; 169:1545–1550. PMID: 9393162.

2. Paulsen SR, Huprich JE, Fletcher JG, et al. CT enterography as a diagnostic tool in evaluating small bowel disorders: review of clinical experience with over 700 cases. Radiographics. 2006; 26:641–657. PMID: 16702444.

3. Maglinte DD, Sandrasegaran K, Lappas JC. CT enteroclysis: techniques and applications. Radiol Clin North Am. 2007; 45:289–301. PMID: 17502218.

4. Wold PB, Fletcher JG, Johnson CD, Sandborn WJ. Assessment of small bowel Crohn disease: noninvasive peroral CT enterography compared with other imaging methods and endoscopy--feasibility study. Radiology. 2003; 229:275–281. PMID: 12944602.

5. Negaard A, Sandvik L, Berstad AE, et al. MRI of the small bowel with oral contrast or nasojejunal intubation in Crohn's disease: randomized comparison of patient acceptance. Scand J Gastroenterol. 2008; 43:44–51. PMID: 18158695.

6. Hara AK, Leighton JA, Heigh RI, et al. Crohn disease of the small bowel: preliminary comparison among CT enterography, capsule endoscopy, small-bowel follow-through, and ileoscopy. Radiology. 2006; 238:128–134. PMID: 16373764.

7. Huprich JE, Fletcher JG, Alexander JA, Fidler JL, Burton SS, Mc-Cullough CH. Obscure gastrointestinal bleeding: evaluation with 64-section multiphase CT enterography--initial experience. Radiology. 2008; 246:562–571. PMID: 18227546.

8. Hakim FA, Alexander JA, Huprich JE, Grover M, Enders FT. CT-enterography may identify small bowel tumors not detected by capsule endoscopy: eight years experience at Mayo Clinic Rochester. Dig Dis Sci. 2011; 56:2914–2919. PMID: 21735085.

9. Hammer MR, Podberesky DJ, Dillman JR. Multidetector computed tomographic and magnetic resonance enterography in children: state of the art. Radiol Clin North Am. 2013; 51:615–636. PMID: 23830789.

10. Lee SS, Kim AY, Yang SK, et al. Crohn disease of the small bowel: comparison of CT enterography, MR enterography, and small-bowel follow-through as diagnostic techniques. Radiology. 2009; 251:751–761. PMID: 19276325.

11. Hara AK, Swartz PG. CT enterography of Crohn's disease. Abdom Imaging. 2009; 34:289–295. PMID: 18649092.

12. Bodily KD, Fletcher JG, Solem CA, et al. Crohn Disease: mural attenuation and thickness at contrast-enhanced CT Enterography--correlation with endoscopic and histologic findings of inflammation. Radiology. 2006; 238:505–516. PMID: 16436815.

13. Vogel J, da Luz Moreira A, Baker M, et al. CT enterography for Crohn disease: accurate preoperative diagnostic imaging. Dis Colon Rectum. 2007; 50:1761–1769. PMID: 17701255.

14. Siddiki HA, Fidler JL, Fletcher JG, et al. Prospective comparison of state-of-the-art MR enterography and CT enterography in small-bowel Crohn's disease. AJR Am J Roentgenol. 2009; 193:113–121. PMID: 19542402.

15. Fletcher JG. CT enterography technique: theme and variations. Abdom Imaging. 2009; 34:283–288. PMID: 18551337.

16. Minordi LM, Vecchioli A, Mirk P, Bonomo L. CT enterography with polyethylene glycol solution vs CT enteroclysis in small bowel disease. Br J Radiol. 2011; 84:112–119. PMID: 20959377.

17. Berther R, Patak MA, Eckhardt B, Erturk SM, Zollikofer CL. Comparison of neutral oral contrast versus positive oral contrast medium in abdominal multidetector CT. Eur Radiol. 2008; 18:1902–1909. PMID: 18414870.

18. Megibow AJ, Babb JS, Hecht EM, et al. Evaluation of bowel distention and bowel wall appearance by using neutral oral contrast agent for multi-detector row CT. Radiology. 2006; 238:87–95. PMID: 16293806.

19. Maglinte DD, Sandrasegaran K, Lappas JC, Chiorean M. CT Enteroclysis. Radiology. 2007; 245:661–671. PMID: 18024448.

20. Vandenbroucke F, Mortele KJ, Tatli S, et al. Noninvasive multidetector computed tomography enterography in patients with small-bowel Crohn's disease: is a 40-second delay better than 70 seconds? Acta Radiol. 2007; 48:1052–1060. PMID: 17963078.

21. Kambadakone AR, Prakash P, Hahn PF, Sahani DV. Low-dose CT examinations in Crohn's disease: impact on image quality, diagnostic performance, and radiation dose. AJR Am J Roentgenol. 2010; 195:78–88. PMID: 20566800.

22. Hara AK, Paden RG, Silva AC, Kujak JL, Lawder HJ, Pavlicek W. Iterative reconstruction technique for reducing body radiation dose at CT: feasibility study. AJR Am J Roentgenol. 2009; 193:764–771. PMID: 19696291.

23. Ghetti C, Ortenzia O, Serreli G. CT iterative reconstruction in image space: a phantom study. Phys Med. 2012; 28:161–165. PMID: 21497530.

24. Lee SJ, Park SH, Kim AY, et al. A prospective comparison of standard-dose CT enterography and 50% reduced-dose CT enterography with and without noise reduction for evaluating Crohn disease. AJR Am J Roentgenol. 2011; 197:50–57. PMID: 21701010.

25. Craig O, O'Neill S, O'Neill F, et al. Diagnostic accuracy of computed tomography using lower doses of radiation for patients with Crohn's disease. Clin Gastroenterol Hepatol. 2012; 10:886–892. PMID: 22469992.

26. Kaza RK, Platt JF, Al-Hawary MM, Wasnik A, Liu PS, Pandya A. CT enterography at 80 kVp with adaptive statistical iterative reconstruction versus at 120 kVp with standard reconstruction: image quality, diagnostic adequacy, and dose reduction. AJR Am J Roentgenol. 2012; 198:1084–1092. PMID: 22528897.

27. Gee MS, Harisinghani MG. MRI in patients with inflammatory bowel disease. J Magn Reson Imaging. 2011; 33:527–534. PMID: 21512607.

28. Ippolito D, Invernizzi F, Galimberti S, Panelli MR, Sironi S. MR enterography with polyethylene glycol as oral contrast medium in the follow-up of patients with Crohn disease: comparison with CT enterography. Abdom Imaging. 2010; 35:563–570. PMID: 19582502.

29. Jensen MD, Kjeldsen J, Rafaelsen SR, Nathan T. Diagnostic accuracies of MR enterography and CT enterography in symptomatic Crohn's disease. Scand J Gastroenterol. 2011; 46:1449–1457. PMID: 21905974.

30. Gee MS, Nimkin K, Hsu M, et al. Prospective evaluation of MR enterography as the primary imaging modality for pediatric Crohn disease assessment. AJR Am J Roentgenol. 2011; 197:224–231. PMID: 21701034.

31. Expert Panel on Gastrointestinal Imaging. American College of Radiology ACR Appropriateness Criteria®: Crohn disease. 2011. 1–17. Available from: http://www.acr.org/~/media/ACR/Documents/AppCriteria/Diagnostic/CrohnDisease.pdf.

32. Fidler JL, Guimaraes L, Einstein DM. MR imaging of the small bowel. Radiographics. 2009; 29:1811–1825. PMID: 19959523.

33. Oto A, Zhu F, Kulkarni K, Karczmar GS, Turner JR, Rubin D. Evaluation of diffusion-weighted MR imaging for detection of bowel inflammation in patients with Crohn's disease. Acad Radiol. 2009; 16:597–603. PMID: 19282206.

34. Oto A, Kayhan A, Williams JT, et al. Active Crohn's disease in the small bowel: evaluation by diffusion weighted imaging and quantitative dynamic contrast enhanced MR imaging. J Magn Reson Imaging. 2011; 33:615–624. PMID: 21563245.

35. Yacoub JH, Oto A. New magnetic resonance imaging modalities for Crohn disease. Magn Reson Imaging Clin N Am. 2014; 22:35–50. PMID: 24238131.

36. Ye BD, Yang SK, Shin SJ, et al. Guidelines for the management of Crohn's disease. Intest Res. 2012; 10:26–66.

37. Schwartz DA, Loftus EV Jr, Tremaine WJ, et al. The natural history of fistulizing Crohn's disease in Olmsted County, Minnesota. Gastroenterology. 2002; 122:875–880. PMID: 11910338.

38. Maconi G, Sampietro GM, Parente F, et al. Contrast radiology, computed tomography and ultrasonography in detecting internal fistulas and intra-abdominal abscesses in Crohn's disease: a prospective comparative study. Am J Gastroenterol. 2003; 98:1545–1555. PMID: 12873576.

39. Prassopoulos P, Papanikolaou N, Grammatikakis J, Rousomoustakaki M, Maris T, Gourtsoyiannis N. MR enteroclysis imaging of Crohn disease. Radiographics. 2001; 21(Special Issue):S161–S172. PMID: 11598255.

40. Maglinte DD, Gourtsoyiannis N, Rex D, Howard TJ, Kelvin FM. Classification of small bowel Crohn's subtypes based on multimodality imaging. Radiol Clin North Am. 2003; 41:285–303. PMID: 12659339.

41. Koh DM, Miao Y, Chinn RJ, et al. MR imaging evaluation of the activity of Crohn's disease. AJR Am J Roentgenol. 2001; 177:1325–1332. PMID: 11717076.

42. Solem CA, Loftus EV Jr, Fletcher JG, et al. Small-bowel imaging in Crohn's disease: a prospective, blinded, 4-way comparison trial. Gastrointest Endosc. 2008; 68:255–266. PMID: 18513722.

43. Masselli G, Casciani E, Polettini E, Gualdi G. Comparison of MR enteroclysis with MR enterography and conventional enteroclysis in patients with Crohn's disease. Eur Radiol. 2008; 18:438–447. PMID: 17899102.

44. Gölder SK, Schreyer AG, Endlicher E, et al. Comparison of capsule endoscopy and magnetic resonance (MR) enteroclysis in suspected small bowel disease. Int J Colorectal Dis. 2006; 21:97–104. PMID: 15846497.

45. Fiorino G, Bonifacio C, Peyrin-Biroulet L, et al. Prospective comparison of computed tomography enterography and magnetic resonance enterography for assessment of disease activity and complications in ileocolonic Crohn's disease. Inflamm Bowel Dis. 2011; 17:1073–1080. PMID: 21484958.

46. Jensen MD, Ormstrup T, Vagn-Hansen C, Ostergaard L, Rafaelsen SR. Interobserver and intermodality agreement for detection of small bowel Crohn's disease with MR enterography and CT enterography. Inflamm Bowel Dis. 2011; 17:1081–1088. PMID: 21484959.

47. Towbin AJ, Sullivan J, Denson LA, Wallihan DB, Podberesky DJ. CT and MR enterography in children and adolescents with inflammatory bowel disease. Radiographics. 2013; 33:1843–1860. PMID: 24224581.

48. Koelbel G, Schmiedl U, Majer MC, et al. Diagnosis of fistulae and sinus tracts in patients with Crohn disease: value of MR imaging. AJR Am J Roentgenol. 1989; 152:999–1003. PMID: 2705359.

49. Essary B, Kim J, Anupindi S, Katz JA, Nimkin K. Pelvic MRI in children with Crohn disease and suspected perianal involvement. Pediatr Radiol. 2007; 37:201–208. PMID: 17180366.