Presentation
Right lower abdominal pain.
Patient Data
Well-defined elongated fluid-filled retrocecal cystic structure with a thin regular wall contiguous with the base of the cecum with mural calcification. No surrounding fat stranding, ascites or thickening of the peritoneal reflections.
Large unilocular cortical cyst of the right kidney as well as small adjacent cyst.
Case Discussion
The CT features are most consistent with appendiceal mucocele.
The mural calcification seen on CT suggests the diagnosis but is seen in less than 50% of cases.
When identifying a mucocele on CT, a search for extraluminal mucin is mandatory, which are low attenuation deposits commonly seen in certain locations:
periappendiceal space
peritoneal cavity
at the surface of abdominal viscera, including ovaries and bowel