- Adnexal torsion should be considered when an ovarian mass is discovered in the appropriate clinical setting.
- Torsion of the adnexal structures may involve the tube or ovary but more often involves both.
- The usual predisposing factor is an ipsilateral adnexal mass that is almost always benign. Of the various ovarian neoplasms, mature cystic teratoma is considered to be the most common cause of adnexal torsion (3.5%–16.1% of cases).
- Torsion infrequently occurs in the absence of an apparent adnexal mass. This is usually seen in children, in whom the adnexa are especially mobile, allowing torsion at the mesosalpinx.
- Adnexal torsion is generally unilateral, with a slight (3:2) right-sided predilection.
- Torsion of the ovarian pedicle produces circulatory stasis that is initially venous but becomes arterial as the torsion and resultant edema progress.
- If the torsion is complete and obstructs the arterial blood supply, gangrenous and hemorrhagic necrosis results.
- When complete torsion is suspected, immediate surgery is necessary to remove the damaged tissue. If left untreated, hemorrhagic infarction of the involved ovary may be followed by infection, leading to peritonitis and, in some cases, death.
- If the torsion is partial and intermittent with spontaneous untwisting, symptoms may subside, only to return within hours, days, or weeks.
- Early diagnosis and treatment may make it possible to conserve normal ovarian structures by untwisting the pedicle and resecting the cysts or tumors.
 Imaging Findings
- US findings of adnexal torsion (including a cystic, solid, or complex mass with or without pelvic fluid, thickening of the wall, and cystic hemorrhage) are nonspecific.
- Identification of the twisted vascular pedicle ("whirlpool sign") at US suggests adnexal torsion and that color Doppler US could be helpful in predicting the viability of the twisted adnexal structures by depicting arterial and venous flow within the twisted vascular pedicle.
 CT and MRI
- Common CT and MR imaging features of adnexal torsion included
- Fallopian tube thickening
- Smooth wall thickening of the twisted adnexal cystic mass
- Uterine deviation to the twisted side.
Patient #2: 8 y/o female with right lower quadrant pain
 See Also
 External Links
- Sung E. Rha, Jae Y. Byun, Seung E. Jung, Jung I. Jung, Byung G. Choi, Bum S. Kim, Hyun Kim, and Jae M. Lee. CT and MR Imaging Features of Adnexal Torsion. RadioGraphics 2002 22: 283-294.