Objective: We evaluated the "ovarian vascular pedicle" sign as a way of differentiating ovarian from subserosal uterine lesions on single-detector helical CT.
Subjects and methods: We prospectively evaluated 131 patients who had a pelvic mass suspected of originating in the ovary or subserosal zone of the uterus and had undergone helical CT before surgery. A total of 108 ovarian lesions and 23 subserosal uterine myomas were confirmed. CT images were analyzed prospectively by consensus of two radiologists who thoroughly evaluated the retrograde tracing of the gonadal veins to the ovary or pelvic mass. To assess the value of analyzing the ovarian vascular pedicle sign in identifying the organ of origin of a pelvic mass, we compared statistical proportions for the frequencies of the sign in ovarian tumors and subserosal uterine myomas by performing the chi-square test. The probabilities for the presence of the ovarian vascular pedicle sign as a positive finding for a pelvic mass of ovarian origin were calculated.
Results: The presence of the ovarian vascular pedicle sign was identified in 92% (99/108) of ovarian masses and in 13% (3/23) of subserosal uterine myomas. The sign was statistically significant (p < 0.01) for differentiating a mass of ovarian origin from a mass of subserosal uterine origin. When the ovarian vascular pedicle sign on helical CT confirmed the ovarian origin, the sensitivity, specificity, positive predictive value and negative predictive value, and diagnostic accuracy were 92% (99/108), 87% (20/23), 97% (99/102), 69% (20/29), and 91% (119/131), respectively.
Conclusion: The presence of the ovarian vascular pedicle sign on helical CT is valuable for confirming the ovarian origin of a pelvic tumor and for differentiating an ovarian tumor from subserosal uterine myoma.