Radiologic diagnosis of appendicitis.

Many articles published in the medical literature have stated that a normal-appearing appendix as seen via contrast enema is inconsistent with the diagnosis of acute appendicitis. This assumes that appendicitis is always associated with complete luminal obstruction of the appendix, and that the length of the normal appendix is known to the interpreter of the x-ray examination. Retrospective analysis of the barium contrast studies of three patients found to have acute appendicitis demonstrated the limitations of this hypothesis. These patients were diagnosed as having acute appendicitis at operation in spite of radiologic evidence of normal-appearing appendices. We review radiologic findings that can be helpful in recognizing this condition and discuss the severe limitations of barium contrast studies in making an accurate diagnosis.