Mimics of Appendicitis, Alternative Nonsurgical Diagnosis with Sonography and CT

1. AJR 2006; 186:1103-1112 Mimics of Appendicitis, Alternative Nonsurgical Diagnosis with Sonography and CT Adriaan C. van Breda Vriesman, Julien B. C. M. Puylaert AJR:186, April 2006 2007.4.19. 8:00am MRI會議室 Presented by int. 黃子青 Supervisor: Pro. 姚維仁

2. Outline • Abstract • Introduction • Normal and Inflamed Appendix • Nonsurgical Mimics of Appendicitis  

3. Abstract • Objective • Imaging features • Nonsurgical disorders + Clinical signs of appendicitis • Conclusion: • Sonographic & CT features Self-limiting or be treated conservatively avoid nontherapeutic appendectomy and unnecessary hospitalization

4. Normal Appendix • Outer diameter of the appendix <6-7 mm

5. Normal Appendix • Air-filled nondistended appendix

6. Inflamed Appendix hyperechoic inflamed fat (arrowheads) hypervascularity of appendiceal wall

7. Inflamed Appendix fluid-filled distended appendix Extramural changes with fat stranding on CECT

8. Inflamed Appendix • Signs of inflammation • Appendicolith • Cecal apical thickening • Color Doppler sonography: hypervascularity of the appendix wall

9. Nonsurgical Mimics of Appendicitis • Mesenteric adenitis • Bacterial ileocecitis • Epiploic Appendagitis • Omental infarction • Colonic Diverticulitis • Ileocecal Crohn's Disease • Ileocecal Intussusception • Pelvic Inflammatory Disease • Urolithiasis • Rectus sheath hematoma

10. Nonsurgical Mimics of Appendicitis • Mesenteric adenitis : 2nd RLQ pain • inflammation (R’t) mesenteric lymph nodes • Normal appendix • self-limiting clustered adenopathy

11. Nonsurgical Mimics of Appendicitis • Bacterial ileocecitis • Yersinia, Campylobacter, or Salmonella spp • Image: • Mural thickening of the terminal ileum and cecum • No inflammation of the surrounding fat • Moderate mesenteric adenopathy. Infectious ileocecitis caused by Yersinia, Campylobacter, and Salmonella: Clinical, radiological and US findings. Eur Radiol 1997; 7:3–9

12. Bacterial Ileocecitis • terminal ileum and cecum :moderate mural thickening • surrounded by normal noninflamed fat 39 y/o, male

13. Epiploic Appendagitis • Epiploic appendage: torsion or 2° inflammation • self-limiting disease hyperechoic inflamed fatty mass fatty lesion contains hyperdense ring Colon

14. Omental infarction • R’t omentum: infarcted fatty tissue inflamed intraperitoneal fat omental fat: cakelike, slightly dense inflamed

15. Differential Diagnosis • ovoid inflamed fatty mass • Shape and size of lesion suggest epiploic appendagitis • No hyperdense ring  D.D.: Epiploic Appendagitis Omental infarction  All benign dz

16. Colonic Diverticulitis cecal wall : fat stranding inflamed cecal diverticulum surrounded by hyperechoic fat.

17. inflamed cecal diverticulum (arrow) with fecalith surrounded by fat stranding.

18. Ileocecal Crohn's Disease terminal ileum: transmural wall thickening surrounding fat : hyperechoic inflammatory changes

19. Ileocecal Crohn's Disease • wall thickening and luminal narrowing of terminal and preterminal ileum (arrowheads) with regional fat stranding.

20. Ileocecal Intussusception • Targetlike mass , distal ileum into cecum

21. Pelvic Inflammatory Disease TVS: CECT enlarged ovary free pelvic fluid

22. Urolithiasis

23. Rectus sheath hematoma • painful palpable mass under anticoagulant therapy Fluid-fluid level partly hyperdense mass

24. Nonsurgical Mimics of Appendicitis • Mesenteric adenitis, Bacterial ileocecitis , Epiploic Appendagitis , Omental infarction, Colonic Diverticulitis, Ileocecal Crohn's Disease , Ileocecal Intussusception , Pelvic Inflammatory Disease, Urolithiasis, Rectus sheath hematoma • correct imaging diagnosis • prevents an unnecessary operation or hospitalization.