Role of Imaging in Assessment of Adnexal Torsion and Ovarian Viability.

Ovarian torsion is dened as partial or complete rotation of the ovarian vascular pedicle and causes obstruction to venous outow and arterial inow. Ovarian torsion is usually associated with a cyst or tumor, which is typically benign; the most common is mature cystic teratoma. Ultrasonography (US) is the primary imaging modality for evaluation of ovarian torsion. Ultrasonography features of ovarian torsion include a unilateral enlarged ovary, uniform peripheral cystic structures, a coexistent mass within the affected ovary, free pelvic uid, lack of arterial or venous ow, and a twisted vascular pedicle.