Figure 4

Ultrasound features of appendicitis. On longitudinal images, the inflamed, non perforated appendix appears as a fluid-filled, uncompressible, blind-ending tubular structure. The maximal appendix diameter, from outside wall to outside wall, is greater than 6 mm. (a) In early non perforated appendicitis, on the longitudinal images an inner echogenic lining representing sub-mucosa can be identified.(b)