ABSTRACT
Acute appendicitis is one of the most frequent causes of acute abdomen. Event though its mortality has been significantly reduced, the high percentage of negative laparotomies changed in the last 40 years reaching at present an average of 20-25%. Several radiological methods have being proposed in order to improve a diagnostic effectiveness, however they have showed a limited value. Computerized tomography and ultrasonography has been used, mainly for the diagnosis of complications of acute appendicitis and few studies related to its utility in early diagnosis have been published. The technique of ultrasonographic examination and the characteristics of the normal and inflamed appendix are discussed as well as the sonographic appearance of appendicular mass, sensibility and method controversy.