[Echography and computerized tomography in the diagnosis of complex abdominal lesions]

Complex abdominal lesions include a variety of pathologies, such as septated, infected, and hemorrhagic cysts, abscesses, tumors, and fluid collections of different etiology. These lesions present diagnostic difficulties with both Ultrasonography (US) and Computed Tomography (CT), since findings may not be present or, when present, are not specific. Keeping these limitations in mind, we evaluated 105 patients (111 abdominal lesions) with both US and CT in order to compare their adequacy in predicting the nature of the lesion. On the basis of US and CT results, complex abdominal lesions were divided in four classes: class I includes 43 cases in which both examinations gave the same contribution to the definition of the nature of the lesion, class II (14 lesions, mainly sepimentated cysts), in which US was superior to CT, class III includes 45 cases in which CT was superior to US, mainly in case of hemorrhagic cysts, abscesses, fluid collections and, less frequently, cystic tumors; class IV includes 9 cases in which US and CT results were complementary, which allowed the nature of the lesion to be defined. In conclusion, US and CT enable the identification and the characterization of complex abdominal lesions; an association of the two investigations enhances their diagnostic value. As a rule, CT is superior when the content of the lesion is either gas or hemorrhage, and in the definition of its peripheral wall. US is always superior in assessing septa, and sometimes even vegetations.