MDCT enterography for evaluation of Crohn's disease

Size: px

Start display at page:

Download "MDCT enterography for evaluation of Crohn's disease"

Agnes Lee
5 years ago
Views:

1 MDCT enterography for evaluation of Crohn's disease Poster No.: C-1588 Congress: ECR 2010 Type: Educational Exhibit Topic: GI Tract Authors: G. Ballester, Y. M. López-Álvarez, A. A. Gómez, E. A. Torres, J. Lojo, E. Colón; San Juan/PR Keywords: MDCT, Crohn's disease, Bowel Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 37

2 Learning objectives 1. To review the etiology, demographics, pathophysiology, diagnosis and treatment of Crohn's Disease (CD). 2. To review the technique of MDCT enterography (CTE). 3. To understand the value of MDCT enterography for the diagnosis and staging of Crohn's disease (CD). 4. To describe the most common findings of CD in MDCT enterography with surgical and pathologic correlations. Background Etiology of Crohn's Disease (Fig. 1 on page 6) Crohn's disease (CD) is a chronic, episodic, idiopathic inflammatory bowel condition, which may involve any part of the gastrointestinal tract, particularly the small and large bowel. The etiology is unknown, but evidence suggests that a genetic predisposition combined with an abnormal interaction (immune response) between the gut and enteric microorganisms, may play a role in the pathogenesis. Epidemiology of Crohn's Disease Approximately 500,000 people in the United States have CD. Prevalence: 144 to 198 cases/100,000 persons It appears to be more common in northern latitudes and Caucasians. Most cases are diagnosed before the age of 30. Page 2 of 37

3 -Second small peak at 6th to 8th decades. Equally affects men and women. Pathophysiology of Crohn's Disease (Fig. 2 on page 6) -Initial lesion is a focal inflammatory infiltrate followed by ulceration of the mucosa. -Inflammatory cells invade deep layers of the bowel wall and forms noncaseating granulomas. -Small ulcerations form deep ulcers which give a cobblestone appearance to the mucosa. -Transmural inflammation results in bowel thickening and narrowing to the lumen. -Progression into obstruction, fistulization, micro perforation and abscess formation. -Nearly 90 % of patients develop perianal disease. -Perianal disease can precede bowel disease by several years. Signs and symptoms of Crohn's Disease Patients usually present with abdominal pain and diarrhea, as well as fever and weight loss. Most patients experience periods of flare ups, followed by episodes of remission when the symptoms decrease or even disappear. - Patients have a poor quality of life in general. Diagnosis of Crohn's Disease Initial diagnosis of CD can be very difficult. Page 3 of 37

4 - No single diagnostic test allows unequivocal diagnosis. It is usually made by a combination of clinical, laboratory, histological, and imaging findings. Imaging findings can provide supportive evidence for the diagnosis of CD. The location and severity of CD is critical for determining patient treatment. MDCT enterography is an excellent tool for those purposes. Treatment of Crohn's Disease Goals -Induce and maintain clinical remission -Enhance quality of life -Avoid long-term medication toxicity Multiple medical and surgical therapies are available. -Depends on clinical presentation and the presence of complications. -Treatment success depends on accurate diagnosis and assessment of extent of disease. -It is necessary to assess the subtype, location, and severity of disease. -MDCT enterography is a powerful tool for those purposes. Medical management (most patients) -Anti-inflammatory drugs -Inmunomodulatory drugs Page 4 of 37

5 Surgical management -Conservative surgery (no resection) -strictureplasty (Fig. 3 on page 7) -Bypass surgery -Complete surgical resection Between 41% and 57% of patients with fistulizing disease will require surgery. Initially, patients with small fistulas are treated medically. Patients with large or multiple fistulas, may need surgical treatment. -Particularly if they are accompanied by persistent symptoms, such as fever or abdominal pain, or if they are related to abscess formation. Indications for Surgery in Crohn's Disease Absolute: -Free perforation -Massive hemorrhage -Dysplasia or cancer -Chronic high grade obstruction Relative: -Intractable disease -Complex fistulas and abscess -Perianal complications Pathology in Crohn's Disease Page 5 of 37

Characteristic pathologic findings of CD: -transmural granulomatous inflammation (Fig. 4 on page 7) -deep ulcers which may progress to sinus tracts and fistulae (Fig.

6 Characteristic pathologic findings of CD: -transmural granulomatous inflammation (Fig. 4 on page 7) -deep ulcers which may progress to sinus tracts and fistulae (Fig. 5 on page 8) -strictures that may lead to intestinal obstruction -discontinuous involvement of the diseased segments (Fig. 6 on page 9) Images for this section: Fig. 1: Etiology of Crohn's Disease. Probably is multifactorial. Different hypothesis: Persistent infection -Dysbiosis (Protective vs. aggressive bacteria) Immune response to bacterial byproducts in the lymphoid follicles -Dysregulated immune response, genetic mediated susceptibility -Deficient intestinal defenses Page 6 of 37

To initiate the Finney stricturoplasty, an incision is made along the anti-mesenteric margin. The intestine is then folded in a Ushape configuration.

7 Fig. 2: Pathophysiology of Crohn's Disease. Fig. 3: The side-to-side stricturoplasty (Finney) is utilized for long strictures (>10 cm). This procedure requires that the intestine be supple enough to bend into a U-shape and still allow for a tension-free anastomosis. To initiate the Finney stricturoplasty, an incision is made along the anti-mesenteric margin. The intestine is then folded in a Ushape configuration. The posterior portion is closed with continuous sutures as is the anterior layer with inversion of the mucosal layer. Concerns about bacterial overgrowth in the diverticulum-like sac extending from the intestine, and about recurrent stricturing within the afferent limb just proximal to the diverticulum, have led to several proposed modifications of this technique. Page 7 of 37

8 Fig. 4: Lymphocytic infiltration with granuloma formation (4x) Page 8 of 37

9 Fig. 5 Page 9 of 37

10 Fig. 6: Skip lesions (normal mucosa between two diseased segments (2x) Page 10 of 37

11 Imaging findings OR Procedure details MDCT enterography (CTE) Technique Multidetector row computed tomography (MDCT) -Much improved temporal and spatial resolution. -Volumetric acquisition allows for improved multiplanar reconstruction. CTE uses a large volume of neutral enteric contrast for intraluminal bowel distention and better delineation of mucosal enhancement. Dynamic intravenous (IV) contrast administration with delayed scanning optimizes bowel wall enhancement. Adequate luminal distention can usually be achieved with oral hyperhydration obviating nasoenteric intubation and making CTE a useful, well-tolerated study for the evaluation of diseases affecting the mucosa and bowel wall. CTE protocol and technical parameters Low density enteric contrast with sorbitol (diminishes water reabsorption from the GI tract) ml in 60 minutes -Water could be another option but not optimal ( ml in minutes). 150 ml of iodinated contrast medium at a rate of 4 ml/sec. *18 G angio at antecubital fossa preferred Images acquired seconds after start of contrast injection. Collimation: 0.8 mm Slice thickness (width): 2.0 mm Page 11 of 37

12 Reconstruction interval (increment): 1.0 mm *Coronal reformatted images: 3.0 mm thickness (width) 2.0 mm interval (increment) Only post contrast-enhanced images to decrease radiation dose. Oblique and curved reformatted images can be obtained at the workstation in multiple planes of imaging when abnormal findings are identified. MDCT enterography (CTE) indications Crohn's disease -diagnosis and staging Abdominal pain Diarrhea Diffuse small bowel diseases Gastrointestinal (GI) bleeding and small bowel tumors (triple phase CTE is preferred) Normal MDCT enterography (CTE) (Fig. 1 on page 15) Mucosal enhancement -Homogeneous -Jejunum > ileum -Up to 110 HU in the jejunum -Depends on degree of bowel distention Page 12 of 37

13 Bowel wall thickness: < 3 mm (distended) -If collapsed: -Jejunum - 7 mm -Ileum - 5 mm Small bowel luminal distention: < 3 cm Advantages of MDCT enterography (CTE) over routine CT scan CTE allows for specific clinical staging of CD. Useful to detect the extra-enteric complications of CD such as abscess, as well as, small bowel mucosal inflammation associated with active CD. Particularly useful for evaluation and detection of penetrating CD. Imaging Findings of Crohn's Disease in CTE Indicators of active disease (Figs. 2 on page 16, 3 on page 17, 4 on page, 5 on page 18, 6 on page 18, 7 on page 20, 8 on page 20, 9 on page 21, 10 on page 21, 17 on page 26, 24 on page 32) 1. Mucosal hyperenhancement (sensitivity >80%) (Figs. 2 on page 16, 3 on page 17, 6 on page 18, 17 on page 26, 24 on page 32) -Best indicator of active disease. 2. Bowel wall thickening (sensitivity and specificity - 75%) (Figs. 4 on page page 26), 5 on page 18, 6 on page 18, 11 on page 22, 17 on -May cause acute reversible luminal narrowing. 3. Mural stratification (bowel wall thickening with enhancement) - Page 13 of 37

14 (sensitivity > 80%) -bilaminar appearance (submucosal inflammatory infiltration) (Fig. 2 on page 16) -trilaminar appearance (submucosal edema) (Figs. 3 on page 17, 6 on page 18) 4. Engorged vasa recta - "comb sign" (most specific sign) (Figs. 2 on page 16, 6 on page 18, 10 on page 21) -correlate with severe, advanced, active disease 5. Perienteric inflammatory fat stranding (highly specific) 6. Other findings/complications -abscess (Figs. 6 on page 18, 14 on page 24), fistula (Figs. 7 on page 20, 8 on page 20, 9 on page 21, 10 on page 21, 11 on page 22, 12 on page 23, 13 on page 23, 14 on page 24), microperforation (Fig. 15 on page 25) Indicators of chronic disease (Figs. 16 on page 25, 17 on page 26, 18 on page, 19 on page 28, 20 on page 29, 21 on page 29, 22 on page, 23 on page 31, 24 on page 32) 1. Fibrofatty proliferation ("Creeping fat sign") (Figs. 16 on page 25, 17 on page 26) 2. Submucosal fatty infiltration (Fig. 18 on page ) 3. Fixed (irreversible) stricture (Figs. 19 on page 28, 20 on page 29, 21 on page 29) -Mucosal hyperenhancement in a stricture is evidence of active disease. 4. Pseudo-sacculations (Fig. 22 on page ) 5. Pseudo-polyp (Fig. 23 on page 31) Page 14 of 37

15 Imaging Pitfalls of CTE Suboptimal luminal distention (Fig. 25 on page 33) -Causes "pseudohyperenhancement" of the mucosa and apparent bowel wall thickening. Suboptimal timing of contrast bolus (Fig. 26 on page 33) -Causes poor enhancement of the bowel mucosa Images for this section: Page 15 of 37

16 Fig. 1: Coronal MPR in a normal CTE Page 16 of 37

17 Fig. 2 Page 17 of 37

18 Fig. 3: Trilaminar mural stratification = Submucosal edema (arrows) Fig. 4: MDCT enterography in a 28 y/o male patient with active CD. (a) Parasagittal reformatted image demonstrates distal ileum luminal narrowing (arrowhead), mucosal hyperenhancement with trilaminar mural stratification (yellow arrow), engorgement of the vasa recta (white arrow) and perienteric fat stranding. Page 18 of 37

Fig. 5: (a) Curved reformatted image demonstrates luminal narrowing at the sigmoid colon, with mucosal hyperenhancement and bilaminar mural stratification (arrowheads) and engorgement of the vasa

(b) Surgical resected gross specimen shows a segment of sigmoid colon with evidence of severe active disease and with "creeping fat" (black arrows). Bladder (b). Fig.

19 Fig. 5: (a) Curved reformatted image demonstrates luminal narrowing at the sigmoid colon, with mucosal hyperenhancement and bilaminar mural stratification (arrowheads) and engorgement of the vasa recta (yellow arrows). Two mural abscesses (white arrows) are also seen at the wall of the sigmoid colon. (b) Surgical resected gross specimen shows a segment of sigmoid colon with evidence of severe active disease and with "creeping fat" (black arrows). Bladder (b). Fig. 6: 16 y/o female patient with CD presenting with lower abdominal pain. MDCT enterography axial images show (a) mucosal hyperenhancement with trilaminar mural stratification (yellow arrows), prominent engorgement of the vasa recta, "comb sign", (arrowheads) and perienteric fibrofatty proliferation and inflammatory changes. (b) Image Page 19 of 37

7: (a) Oblique coronal reformatted images demonstrates a stricture (arrowheads) at the distal ileum with mucosal hyperenhancement and

20 of same patient at a lower level demonstrates a fluid collection with thick, irregular enhancing walls, consistent with abscess/phlegmon formation(*). Uterus (u). Fig. 7: (a) Oblique coronal reformatted images demonstrates a stricture (arrowheads) at the distal ileum with mucosal hyperenhancement and mild proximal bowel dilatation. There is a complex entero-enteric fistula (yellow arrows) identified at the distal ileum. There is also evidence of engorgement of the vasa recta (white arrow) and several pseudosacculations (*). Page 20 of 37

21 Fig. 8: 26 y/o female patient with CD presenting with abdominal pain and diarrhea. MDCT enterography (a) axial and (b) coronal reformatted images show a complex fistula with multiple fistulous tracts confluent at lower abdomen/supravesical region. Luminal narrowing, bilaminar mural stratification and surrounding fibrofatty proliferation are also demonstrated. Bladder (b). Fig. 9: 23 y/o male patient with CD presenting with worsening abdominal pain. MDCT enterography (a) oblique axial image at right pelvic region show multiple confluent fistulous tracts (yellow arrow), with evidence of mucosal hyperenhancement at the involved ileal loops. (b) Oblique coronal image show to a better extent entero-enteric fistulae (yellow arrows) between segments with active disease. Bladder (b). Page 21 of 37

(b) Sagittal reformatted image show to a better extent entero-cutaneous fistulae (yellow arrows) involving a small bowel segment with active disease. Bladder (b). Fig.

22 Fig. 10: 23 y/o male patient with CD presenting with abdominal pain and suspected enterocutaneous fistula. MDCT enterography (a) oblique axial suggest a fistulous tract from small bowel loops that show mucosal hyperenhancement adjacent to the anterior abdominal wall skin (yellow arrows). (b) Sagittal reformatted image show to a better extent entero-cutaneous fistulae (yellow arrows) involving a small bowel segment with active disease. Bladder (b). Fig. 11: MDCT enterography of same patient, with history of prior bowel resection. (a) Oblique axial image show luminal narrowing, mucosal hyperenhancement, bilaminar and trilaminar mural stratification at the distal ileum. There is also a fistulous tract between the Page 22 of 37

12: MDCT enterography oblique coronal (a) and sagittal images at RLQ show a fistulous tract between two segments of distal ileum with

23 ileal segment with active disease. Surgical bowel markers are seen from prior ileocolonic anastomosis. (b) Oblique coronal image show to a better extent entero-enteric fistulae between segments with active disease. Bladder (b). Fig. 12: MDCT enterography oblique coronal (a) and sagittal images at RLQ show a fistulous tract between two segments of distal ileum with associated fibrofatty proliferation and prominent inflammatory changes (yellow arrows). This was not well appreciated on the axial images and emphasizes the usefulness of reformatted images. Page 23 of 37

24 Fig. 13: 34 y/o female patient with CD presenting with lower abdominal pain. (a,b) MDCT oblique coronal reformatted images demonstrate a short segment stricture (arrowheads) at the distal ileum. There is also a fistulous communication (yellow arrow) between two ileal segments. The fistulous tract was not seen on axial images. Page 24 of 37

25 Fig. 14: 53 y/o female patient with CD presenting with RLQ pain. MDCT enterography oblique coronal reformatted image shows a diseased segment of distal ileum with a fistulous communication reaching the subcutaneous soft tissues. There is a fluid collection with enhancing walls, consistent with abscess formation. Fig. 15 Page 25 of 37

26 Fig. 16: Terminal ileum with active disease: - Bowel wall thickening - Mucosal hyperenhacement with mural stratification (bilaminar) Page 26 of 37

27 Fig. 17 Page 27 of 37

28 Fig. 18 Page 28 of 37

29 Fig. 19 Fig. 20 Page 29 of 37

30 Fig. 21 Page 30 of 37

31 Fig. 22 Page 31 of 37

areas of mucosal hyperenhancement, bilaminar mural stratification, and short strictures

32 Fig. 23 Fig. 24: (a) Curved reformatted image demonstrates luminal narrowing at the distal ileum, with areas of mucosal hyperenhancement, bilaminar mural stratification, and short strictures (white arrows) with pseudosacculation (arrowhead). Fistulous tract (yellow arrow) is again noted communicating with the phlegmonous process (*). (b) Surgical Page 32 of 37

33 resected gross specimen of distal ileum shows pseudosacculations (arrowheads) and a short stricture (white arrow). "Creeping fat" is again noted. (black arrows). Bladder (b). Fig. 25: Pitfalls: Suboptimal luminal distention: causes "pseudohyperenhancement" of the mucosa and apparent bowel wall thickening. Page 33 of 37

34 Fig. 26: Pitfalls: Suboptimal timing of contrast bolus results in poor enhancement of the bowel mucosa Page 34 of 37

35 Conclusion MDCT enterography (CTE) is a powerful tool and has become the modality of choice for the evaluation of patients with Crohn's Disease (CD). This technique allows for the evaluation of intra and extraenteric manifestations of the disease. MDCT evaluates: -Intra and extraenteric involvement -Disease location and extension -Severity of disease -Acute vs. chronic manifestations ***That information is crucial for adequate patient treatment.*** Patients with CD need a multidisciplinary approach, with close collaboration between radiologists, gastroenterologists and surgeons for the accurate assessment and management of the disease and its complications. Thus, radiologists should become familiar with the technical aspects of CTE in order to provide the clinicians with a more accurate diagnosis and staging of CD and its many complications. Personal Information Gory Ballester, MD Department of Diagnostic Radiology School of Medicine Medical Sciences Campus University of Puerto Rico Page 35 of 37

36 San Juan, Puerto Rico PO Box San Juan, PR ; x- 6731, 6733 References Sandra Tochetto, Vahid Yaghmai. CT Enterography: Concept, Technique and Interpretation. Radiologic Clinics of North America, January 2009 Volumen 47, Issue 1, Pages Herlinger H, Caroline DF. Crohn's disease of the small bowel. In: Gore RM, Lenine MS, eds. Textbook of gastrointestinal radiology. 2nd ed. Philadelphia, Pa: Saunders, 2000; Paulsen S, Huprich J, Hara A. CT Enterography: Noninvasive Evaluation of Cronh's Disease and Obscure Gastrointestinal Bleed. Radiologic Clinics of North America, March 2007, Volume 45, Issue 2, Pages Scott R. Paulsen, James E. Huprich, Joel G. Fletcher, et al. CT Enterography as a Diagnostic Tool in Evaluating Small Bowel Disorders: Review of Clinical Experience with over 700 Cases. RadioGraphics, May 2006; 26: Reittner P, Goritschnig T, Petritsch W, et al. Multiplanar spiral CT enterography in patients with Crohn's disease using a negative oral contrast material: initial results of a noninvasive imaging approach. Eur Radiol 2002;12: Page 36 of 37

37 Booya F, Fletcher JG, Huprich JE, et al. Active Crohn disease: CT findings and interobserver agreement for enteric phase CT enterography. Radiology 2006; 241: Bodily KD, Fletcher JG, Solem CA, Johnson CD, et al. Crohn Disease: mural attenuation and thickness at contrast-enhanced CT Enterography-correlation with endoscopic and histologic findings of inflammation. Radiology. 2006; 238: Otterson, S. Lundeen, K. Spinelli, et al. Radiographic underestimation of small bowel stricturing Crohn's disease: A comparison with surgical findings. Surgery. 2004; 136 (4): Page 37 of 37

MDCT enterography for evaluation of Crohn's disease

MDCT enterography for evaluation of Crohn's disease Poster No.: C-1588 Congress: ECR 2010 Type: Educational Exhibit Topic: GI Tract - Small Bowel Authors: G. Ballester, Y. M. López-Álvarez, A. A. Gómez,