[Differential diagnosis of cystic intra-abdominal lesions: mucocele of the appendix].

The sonographic appearance of a mucocele of the appendix in a 69-year-old woman is presented. The mucocele showed an atypical localisation in the right upper quadrant just below the gallbladder. This own observation is compared with other case reports in the literature. The value of ultrasound examinations in the diagnosis "mucocele of the appendix" is discussed.