Gray scale B scan characteristics of intra-abdominal cystic masses.

A comparison of the gray scale characteristics of 119 intra-abdominal cystic masses was performed. Each cystic mass was evaluated with regard to: 1) The presence or absence of internal echoes, septa, and fluid-fluid levels; 2) The appearance of the wall; 3) Conformity to adjacent organs and, 4) Changes in the surrounding soft tissues. Abscesses, hematomas, lymphoceles, urinomas, and necrotic tumors were evaluated. Necrotic tumors and some abscesses and hematomas have specific sonographic characteristics. In most cases, a definite diagnosis cannot be made from the sonographic appearance; however, in conjunction with the clinical history, the differential diagnosis can be narrowed to a couple of cystic lesions among the many that may be found in the abdomen. The diagnosis can be confirmed by aspiration under ultrasound. A comparison between these cystic masses and pancreatic pseudocysts, renal cysts, and ovarian cysts was made.