[Rectal endosonography for detection of free fluid in the abdomen].

In a study of 60 patients suspicious of free fluid we found a very high sensitivity of 95% and specificity of 100% with endorectal sonography. In 6 patients free fluid could be shown preoperatively by endorectal ultrasound, whereas transabdominal sonography proved to be negative. We conclude that endorectal sonography should be performed in all cases with a clinical suspicion of free fluid when transabdominal sonography is negative. Rectal endosonography is an easy and less stressful examination which clarifies conditions in the pelvis which are not clearly discernible from the transabdominal sonography.