The wall thickness varies, but if the wall is greater than 6mm, one should also consider uncomplicated acute appendicitis. The internal features vary from anechoic to hyperechoic, and may be dependent. Internal septations, polypoid lesions extending into the lumen and irregular shapes seem to be associated with the malignant variety, although some papillary processes may be seen in mucinous cystadenomas. They may have simple or multiple cystic components and some solid elements. These may even demonstrate infiltration into adjecent organs such as colon, bladder and ureter.
Attenuation is near that of water.
This is from chronic inflammatory precess incited by the irritating mucous. A pitfall is that fluid filled terminal ileum may resemble a mucocele, so delayed scanning may be warranted in some cases. A smooth filling defect at the tip of the cecum is classic. This may give the false appearance of intussusception, which only rarely complicates mucocele. The findings in this case are typical of a mucocele of the appendix.