Nongynecologic applications of transvaginal sonography

Transvaginal sonography has become an invaluable technique for examining the uterus and adnexa, primarily because it provides better spatial resolution than transabdominal sonography does. This characteristic also makes it useful for evaluating the nongynecologic structures in the pelvis. As many of these structures are imaged incidentally during gynecologic transvaginal sonography, familiarity with their normal and abnormal appearances is important. With minor modifications in technique, targeted studies of these structures are easily performed. We illustrate the technique used, normal anatomy seen, and abnormalities commonly encountered in transvaginal sonography of nongynecologic pelvic structures.