Figure 1. (a) Unenhanced CT of the pelvis shows a non-homogeneous midline mass (arrowheads) behind the uterus (U), containing peripheral hypodense lesions. The mass generally has a higher density compared with the left ovary (arrow). Free peritoneal fluid surrounds the mass. (b) 15 mm caudally, the lower extension of the complex mass is seen (arrowhead), with multiple peripheral foci of low attenuation. Note also the free pelvic fluid (arrow).