结肠炎性疾病的CT评价

Mahan Mathur Gillian Lieberman, MD CT evaluation of inflammatory conditions of the colon Mahan Mathur McGill Medicine Class of 2007 Advanced Clerkship in Radiology BIDMC, Harvard Medical School Mahan Mathur Gillian Lieberman, MD Outline 1. Normal CT considerations of Bowel 2. Disease Spectrum • IBD (Crohns, Ulcerative Colitis) • Infectious ( Pseudomembranous Colitis, typhlitis) • Vascular (ischemic) • Diverticulitis • Appendicitis • Epiploic Appendagitis Mahan Mathur Gillian Lieberman, MD Outline 1. Normal CT considerations of Bowel 2. Disease Spectrum • IBD (Crohns, Ulcerative Colitis) • Infectious ( Pseudomembranous Colitis, typhlitis) • Vascular (ischemic) • Diverticulitis • Appendicitis • Epiploic Appendagitis Mahan Mathur Gillian Lieberman, MD Normal CT considerations of Bowel • Advantages: – Ease of availability and performance – Accurate delineation of anatomy – intestinal and extraintestinal + complications – Multidetector CT => short scan times, thin slices, reformations Normal Scout film PACS, BIDMC Normal Axial CT slice, PACS, BIDMC Mahan Mathur Gillian Lieberman, MD Normal CT considerations of Bowel • Normal Colon: – Small Bowel: 3 cm – Large Bowel: 6 cm – Cecum: 9 cm • Bowel wall thickness: – Normal: 3 mm – Distended: 1-2 mm Normal Coronal CT reformation, PACS, BIDMC Normal Sagittal CT reformation PACS, BIDMC Mahan Mathur Gillian Lieberman, MD Outline 1. Normal CT considerations of Bowel 2. Disease Spectrum • IBD (Crohns, Ulcerative Colitis) • Infectious ( Pseudomembranous Colitis, typhlitis) • Vascular (ischemic) • Diverticulitis • Appendicitis • Epiploic Appendagitis Mahan Mathur Gillian Lieberman, MD Patient #1: Scout and Axial Films 29 yo F with 3 wks of abdo pain, anemia and increased WBC PACS, BIDMC PACS, BIDMC Scout Film Axial CT slice: Note the Bowel Wall thickness Mahan Mathur Gillian Lieberman, MD Patient #1: Coronal Reformation PACS, BIDMC Note the distal ileal distribution of Bowel Wall thickness Mahan Mathur Gillian Lieberman, MD Patient #1: Sagittal Reformations Note the difference between small and large bowel wall (seen here is Transverse Colon) thickness PACS, BIDMC PACS, BIDMC Mahan Mathur Gillian Lieberman, MD Patient #1: Coronal Reformation Note the difference between small and large bowel wall thickness PACS, BIDMC Mahan Mathur Gillian Lieberman, MD IBD: Crohn’s • Etiology: unknown • Involvement: mouth to perianal – 80%: small bowel (distal ileum = most common) – 50%: ileocolitis – 20%: limited to colon – sparing of rectum • Clinical Manifestations: – Diarrhea, Abdo pain, Weight Loss, Fever, bleeding – SBO (fibrotic strictures) – Fistula (entero-vaginal/vesical/cutaneous) – Perforation: sinus tracts with serosal penetration Related to Pathophysiology Of Transmural Bowel Wall inflammation Mahan Mathur Gillian Lieberman, MD Crohn’s: Extraintestinal Manifestations Localized Episcleritis Anterior uveitis/iritis. Pyoderma gangrenosum Erythema Nodosum Apthous Stomatitis Mintz et all. Inflamm Bowel Dis. 2004 Trost et all. Postgrad Med J. 2005 Mahan Mathur Gillian Lieberman, MD ERCP showing Sclerosing Cholangitis GallBladder Common Bile Duct Common Hepatic duct Right/Left Hepatic ducts Presti et all. Dig Dis Sci. 1997 Note: Narrow CBD and stenotic CHD with prestenotic dilatation of Left Hepatic Duct + intraheptatic duct pruning Mahan Mathur Gillian Lieberman, MD Crohn’s: Imaging Options – Colonoscopy – Barium studies – CT (sens: 94-100%, spec 95%); sens 70% early stage disease Disadvantage: Limited evaluation of extramural extension + extraintestinal complications Colonoscopy showing Cobblestone Mucosa Lee et all, Endoscopy 2006 Barium study demonstrating a crohns induced bowel Fistula Maconi et all. Am J Gastroenterol. 2003 Mahan Mathur Gillian Lieberman, MD Crohns: Findings on CT • Small bowel, terminal ileum; left sided colitis rare; rectal sparing • Eccentric Wall thickening with contrast enhancement: – 11mm +/- 5.1 • Homogenous or Stratified/segmental appearance (“skip” lesions) – Psedodiverticula • Luminal Narrowing with prestenotic dilatation (“string sign”) • Fibrofatty proliferation adjacent to small bowel segments (“Creeping fat”) -> separation of small bowel loops • Mesenteric Lymphadenopathy (3-8mm): if>1cm -> consider lymphoma • Water Halo and Target Signs => acute bowel injury • Engorged Mesenteric Vessel (“comb sign”) => acute bowel injury • Abscess, Fistulas Mahan Mathur Gillian Lieberman, MD Close-up Axial and Sagittal views of Patient #1’s abdomen Bowel Wall Thickening (>1cm) Comb Sign + Fibrofatty proliferation PACS, BIDMC PACS, BIDMC Mahan Mathur Gillian Lieberman, MD Close-up Axial view of patient #1’s Abdomen Mesenteric Lymphadenopathy: Note size<1cm PACS, BIDMC PACS, BIDMC Mahan Mathur Gillian Lieberman, MD Close-up Coronal View of Patient #1’s Abdomen: Target Sign Target Sign: 1. Outer later for high attenuation: inflamed muscularis propria 2. Middle layer: intermediate (edema)/low attenuation (fat) 3. Inner later: inflamed muscosaPACS, BIDMC Mahan Mathur Gillian Lieberman, MD Follow-up + Summary for Patient #1 • Combination of Clinical and Radiological Findings point to diagnosis of Crohn’s Disease in our patient • Radiological Findings: Distal Ileal Bowel wall thickening with Target sign, Comb sign, fibrofatty proliferation and Mesenteric Lymphadenopathy • Patient had subsequent follow-up with Gastroenterology and a c-scope with biopsies confirming the diagnosis of Crohns Mahan Mathur Gillian Lieberman, MD Patient #2: Scout and Axial images of Abdomen 57yo M with history of Ulcerative Colitis presents with 4 days of watery diarrhea, afebrile, normal WBC. Previous allergic reaction to IV Iodine (thus, no IV contrast given) PACS, BIDMC PACS, BIDMC Mahan Mathur Gillian Lieberman, MD Two Coronal Reformations in different planes for Patient #2 PACS, BIDMC PACS, BIDMC Note: Involvement of Hepatic Flexure Note: Ahaustral, thickened bowel transverse colon Mahan Mathur Gillian Lieberman, MD Sagittal and Axial slices in Patient #2 PACS, BIDMC PACS, BIDMC Ahaustal rectosigmoid colon => likely chronic UCTransverse Colon involvement Mahan Mathur Gillian Lieberman, MD IBD: Ulcerative Colitis • Etiology: unknown • Involvement: Rectum -> Large Bowel – Beware of “backwash Ilietis” • Clinical Manifestations: – Abdo pain, bloody diarrhea, weight loss, fever – Increased risk of colon cancer (increased with duration and extent of colonic involvement) – Toxic megacolon with muscle layer infiltration – Strictures, Abscess • Extraintestinal Manifestations (see Crohn’s) Mahan Mathur Gillian Lieberman, MD Ulcerative Colitis: Imaging Options • Imaging – Flexible Sigmoidoscopy – Colonoscopy – Barium enema – rare use : low sensitivity in mild disease, risk of bowel perforation in severe disease – CT • Rectal involvement + Left sided/pancolitis – occasional backwash ileitis • Symmetric wall thickening: 7.8mm +/- 1.9 • Proliferation of perirectal fat • Target sign, Comb Sign in large bowel • Colon cancer, Toxic Megacolon Tests of choice Mahan Mathur Gillian Lieberman, MD Coronal Slice of Patient #2 and Axial Slice of another patient (patient #3) with UC Ahaustral Transverse colon Sigmoid Colon involvement in a different patient with known Ulcerative colitis and possible rectal stricture PACS, BIDMC PACS, BIDMC Mahan Mathur Gillian Lieberman, MD Axial Slices for patient #3 Stricture: note the increase in bowel wall thickness along the horizontal plane versus the vertical plane Rectal Wall Thickening PACS, BIDMC PACS, BIDMC Mahan Mathur Gillian Lieberman, MD Coronal and Sagittal Views of Patient #3 Target Sign + sparing of small bowel at rectosigmoid junction Rectosigmoid involvement PACS, BIDMC PACS, BIDMC Mahan Mathur Gillian Lieberman, MD Follow-up + Summary for Patient #2 • Again, Combination of Clinical and Radiological Findings point to the diagnosis of UC exacerbation in our patient • Radiological Findings: Rectal wall thickness + exclusive large bowel involvement, perirectal fatty proliferation, target sign in rectosigmoid junction • Subsequent Colonoscopy confirmed the diagnosis in this patient Mahan Mathur Gillian Lieberman, MD Patient #4: Scout and Axial images of Abdomen 86 yo F with Fever, Abdo Pain, watery diarrhea x 2days. Multiple recent hospitalizations. Last June 2006 for pneumonia PACS, BIDMC PACS, BIDMC Note the irregular looking Bowel wall appearance Mahan Mathur Gillian Lieberman, MD Sagittal and Coronal Reformation of Patient #4’s Abdomen PACS, BIDMC PACS, BIDMC Reformations indicate pancolitisSigmoid Wall thickness Mahan Mathur Gillian Lieberman, MD Pseudomembranous Colitis • Etiology: C. Difficile – Nosocomial, s/p antibiotics • Involvement: Pancolitis/isolated colitis • Clinical Manifestations – Asymptomatic carrier, watery diarrhea, abdo pain, fever, high WBC: 5-10d s/p Antibiotics (penicillin, clindamycin, cephalosporins) – Toxic Megacolon: colonic dilatation>7cm Mahan Mathur Gillian Lieberman, MD Pseudomembranous Colitis: Imaging • Imaging: – Sigmoidoscopy/Colonoscopy: • Pseudomembrane plaques – CT Often not necessary: Clinical Diagnosis Kawamoto et all, Radiographics. 1999 Kawamoto et all, Radiographics. 1999 Pathology specimen showcasing plaques (straight arrows) + erythema/ edema (curved arrow) Mahan Mathur Gillian Lieberman, MD Pseudomembranous Colitis: CT Findings – Bowel Wall thickening: 3-32mm (mean 14.7mm) • Irregular, “shaggy” – Target Sign – Accordion Sign: alternating bands of high and low attenuation (contrast trapped between thickened folds): non-specific (also found in other infectious colitis, ischemic colitis) – Ascites: Important in differentiating from IBD (but again, non-specific) Mahan Mathur Gillian Lieberman, MD Close up Axial and normal Axial images of abdomen in Patient #4 Accordion Sign PACS, BIDMC PACS, BIDMC Mahan Mathur Gillian Lieberman, MD Follow-up + Summary for Patient #4 • Clinical history particularly important in this case although, as demonstrated by the radiographic findings, P. Colitis demonstrates an irregular (“shaggy”) wall appearance with an accordion sign +/- ascites that allow for a reasonably distinct appearance • Stool for C. Diff confirmed the diagnosis of P. Colitis. Antibiotic treatment was started for this patient. Mahan Mathur Gillian Lieberman, MD Complication of P. colitis + UC • Toxic Megacolon : bowel wall> 7cm Thoeni et all. Radiology. 2006 Mahan Mathur Gillian Lieberman, MD Outline 1. Normal CT considerations of Bowel 2. Disease Spectrum • IBD (Crohns, Ulcerative Colitis) • Infectious ( Pseudomembranous Colitis, typhlitis) • Appendicitis • Diverticulitis • Vascular (ischemic) • Epiploic Appendagitis Mahan Mathur Gillian Lieberman, MD Typhlitis – Terminal ileum/ Cecal / Asc. colon involvement – Neutropenic patients – Fever, watery/bloody diarrhea – Unknown etiology – Txt: conservative – resolution with return of functioning neutrophils Axial image of abdomen showing circumferential thickening of the cecal wall + pericecal inflammation Horton et all. Radiographics. 2000 Mahan Mathur Gillian Lieberman, MD Appendicitis – Luminal occlusion with venous congestion, ischemia, inflammation – RLQ pain – CT: thickened wall with dilated appendix (>6mm) + pericecal inflammation – Txt: Surgery (risk of perforation) Axial Image of Abdomen showing inflamed appendix and periappendiceal fat stranding Horton et all. Radiographics. 2000 Mahan Mathur Gillian Lieberman, MD Diverticulitis – Outpouchings of colonic musoca/submucosa at site where vessels exit – Etiology: Obstruction by stool/food/inflammation – CT: descending/sigmoid colon wall thickening with pericolic inflammation in patient with diverticulae PACS, BIDMC Diverticulae Axial Image of Abdomen demonstrating mild fat stranding and fascial thickening in 60 yo M with LLQ pain Mahan Mathur Gillian Lieberman, MD Ischemic Colitis – Older population – Ischemia (MI, Arrhythmia, embolus) – Colonic mucosal changes due to restoration of blood flow (free radical damage) – “Watershed” area: distal transverse colon (splenic flexure) + distal descending colon (rectosigmoid junction) Mahan Mathur Gillian Lieberman, MD Epiploic Appendagitis – 1–4-cm, oval, fatty pericolic lesion with surrounding mesenteric inflammation – Associated with torsion/thrombosis – Can be confused clinically with appendicitis – Conservative management Axial image of Abdomen showing peripheral enhancement of fatty epiploic appendage with surrounding mesenteric inflammation. Note the sparing of the large bowel Thoeni et all. Radiology. 2006 Mahan Mathur Gillian Lieberman, MD Summary: clinical history is paramount Thoeni et all. Radiology. 2006 • Crohns: Right sided, distal ileum, left sided (rare) with rectal sparing • UC: Rectal involvement +/- large bowel involvement, occasional ileitis • P. colitis: pancolitis, accordion sign, ascites, Hx of antibiotic use Mahan Mathur Gillian Lieberman, MD References 1. Trost LB, McDonnell JK. Important cutaneous manifestations of inflammatory bowel disease. Postgrad Med J. 2005 Sep;81(959):580-5. Review. 2. Mintz R, Feller ER, Bahr RL, Shah SA. Ocular manifestations of inflammatory bowel disease. Inflamm Bowel Dis. 2004 Mar;10(2):135-9. Review 3. Presti ME, Neuschwander-Tetri BA, Vogler CA, Janney CG, Roche JK. Sclerosing cholangitis, inflammatory bowel disease, and glomerulonephritis: a case report of a rare triad. Dig Dis Sci. 1997 Apr;42(4):813-6. Review 4. Furukawa A, Saotome T, Yamasaki M, Maeda K, Nitta N, Takahashi M, Tsujikawa T, Fujiyama Y, Murata K, Sakamoto T. Cross-sectional imaging in Crohn disease. Radiographics. 2004 May-Jun;24(3):689-702. Review. 5. Lee YJ, Yang SK, Byeon JS, Myung SJ, Chang HS, Hong SS, Kim KJ, Lee GH, Jung HY, Hong WS, Kim JH, Min YI, Chang SJ, Yu CS. Analysis of colonoscopic findings in the differential diagnosis between intestinal tuberculosis and Crohn's disease. Endoscopy. 2006 Jun;38(6):592-7. Epub 2006 Apr 27. 6. Maconi G, Sampietro GM, Parente F, Pompili G, Russo A, Cristaldi M, Arborio G, Ardizzone S, Matacena G, Taschieri AM, Bianchi Porro G. 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 Jul;98(7):1545-55. 7. Kawamoto S, Horton KM, Fishman EK. Pseudomembranous colitis: spectrum of imaging findings with clinical and pathologic correlation. Radiographics. 1999 Jul-Aug;19(4):887-97. Review. 8. Thoeni RF, Cello JP. CT imaging of colitis. Radiology. 2006 Sep;240(3):623-38. Review. 9. Horton KM, Corl FM, Fishman EK. CT evaluation of the colon: inflammatory disease. Radiographics. 2000 Mar-Apr;20(2):399-418. Mahan Mathur Gillian Lieberman, MD • Acknowledgements – Dr. V. Raptopoulos – Dr. J. Kruskal – Dr. A. Hochberg – Dr. K. Mani – Dr. G. Lieberman – George Lynskey – Pamela Lepkowski – Larry Barbaras Chisasibi, Northern Quebec, summer 2003 CT evaluation of inflammatory conditions of the colon Outline Outline Normal CT considerations of Bowel Normal CT considerations of Bowel Outline Patient #1: Scout and Axial Films Patient #1: Coronal Reformation Patient #1: Sagittal Reformations Patient #1: Coronal Reformation IBD: Crohn’s Crohn’s: Extraintestinal Manifestations ERCP showing Sclerosing Cholangitis Crohn’s: Imaging Options Crohns: Findings on CT Close-up Axial and Sagittal views of Patient #1’s abdomen Close-up Axial view of patient #1’s Abdomen Close-up Coronal View of Patient #1’s Abdomen: Target Sign Follow-up + Summary for Patient #1 Patient #2: Scout and Axial images of Abdomen Two Coronal Reformations in different planes for Patient #2 Sagittal and Axial slices in Patient #2 IBD: Ulcerative Colitis Ulcerative Colitis: Imaging Options Coronal Slice of Patient #2 and Axial Slice of another patient (patient #3) with UC Axial Slices for patient #3 Coronal and Sagittal Views of Patient #3 Follow-up + Summary for Patient #2 Patient #4: Scout and Axial images of Abdomen Sagittal and Coronal Reformation of Patient #4’s Abdomen Pseudomembranous Colitis Pseudomembranous Colitis: Imaging Pseudomembranous Colitis: CT Findings Close up Axial and normal Axial images of abdomen in Patient #4 Follow-up + Summary for Patient #4 Complication of P. colitis + UC Outline Typhlitis Appendicitis� Diverticulitis Ischemic Colitis Epiploic Appendagitis Summary: clinical history is paramount References Slide Number 45