PURPOSE: To evaluate characteristic CT features of twisted ovarian tumors and to assess the diagnostic value of the existence of twisted vascular pedicle in torsion of ovarian tumors. MATERIALS AND METHODS: Weretrospectively reviewed the clinical and CT findings in eleven patients with ovarian tumor torsion confirmed bysurgery. Pre- and post-contrast CT were available in nine patients and post-contrast CT in two. All twisted ovaries, tubes, and tumors showed hemorrhagic infarction and necrosis. RESULTS: All patients had twisted vascular pedicle of the ovarian tumor evaluated by CT. Eight patients with left ovarian tumor had twisted vascular pedicleon the left side of the tumor, and three patients with right ovarian tumor on the right side of the tumor. Themorphologic characteristics of twisted vascular pedicle were coiled target appearance (4 cases), beak appearance(3 cases), doughnut appearance (3 cases), and mass with irregular margin (1 case). High density on precontrast CT scan was present in the pedicle in four cases and linear contrast enhancement was seen in the peripheral portionof the pedicle in four cases. The shape, density and location of ovarian tumors were inconsistent, however, contrast enhancement was not seen in all patients. Other findings were uterine deviation, loss of fat plane andpelvic fluid. CONCLUSION: Detection of twisted vascular pedicle by CT may be useful for the diagnosis of ovariantumor torsion.