Table 2 US signs of acute appendicitis [16]
From: Appendix-preserving elective herniorrhaphy for de Garengeot hernia: two case reports
Direct signs | Indirect signs |
|---|---|
Non-compressibility of the appendix | Free fluid surrounding appendix |
Perforation: appendix might be compressible | Local abscess formation |
Diameter of the appendix > 6 mm | Increased echogenicity of local mesenteric fat |
Single wall thickness ≥ 3 mm | Enlarged local mesenteric lymph nodes |
Unclear wall structure | Thickening of the peritoneum |
Hypoechoic fluid-filled lumen | Secondary small bowel obstruction |
Hyperechoic mucosa/submucosa | |
Hypoechoic muscularis layer | |
Appendicolith: hyperechoic with posterior shadowing | |
Colour Doppler and contrast-enhanced US: | |
Hypervascularity in early stages of acute appendicitis | |
Hypo- to avascularity in abscess and necrosis |