CT and MR Imaging Features of Adnexal Torsion

Abstract

In adnexal torsion, the ovary, ipsilateral fallopian tube, or both twist with the vascular pedicle, resulting in vascular compromise. Unrelieved torsion is likely to cause hemorrhagic infarction as the degree of arterial occlusion increases. Therefore, early diagnosis is important to preserve the affected ovary. Adnexal torsion commonly accompanies an ipsilateral ovarian neoplasm or cyst but can also occur in normal ovaries, usually in children. Although ultrasonography is typically the initial emergent examination, computed tomography (CT) and magnetic resonance (MR) imaging may also be useful diagnostic tools. Common CT and MR imaging features of adnexal torsion include fallopian tube thickening, smooth wall thickening of the twisted adnexal cystic mass, ascites, and uterine deviation to the twisted side. Uncommon imaging findings in adnexal torsion that are specific to hemorrhagic infarction include hemorrhage in the thickened fallopian tube, hemorrhage within the twisted ovarian mass, and hemoperitoneum. Additional imaging findings that can suggest hemorrhagic infarction include eccentric smooth wall thickening exceeding 10 mm in a cystic ovarian mass converging on the thickened fallopian tube and lack of contrast enhancement of the internal solid component or thickened wall of the twisted ovarian mass. Early diagnosis can help prevent irreversible structural damage and may allow conservative, ovary-sparing treatment.

Preoperative Magnetic Resonance Imaging Diagnosis of Ovarian Torsion

“…These include ovarian enlargement, twisted pedicle, ovarian hemorrhage, ascites, deviation of the uterus to the side with the twist, and fallopian tube thickening (6)(7)(8)(9). Among these, the present results indicate that identifying a twisted pedicle was the most useful characteristic for the diagnosis of ovarian torsion.…”

“…First, this was a retrospective study with a relatively small cohort of patients at a single center, potentially resulting in selection bias because the post-hoc power analysis showed a power 6 Iran J Radiol. In Press(In Press):e14270.…”

“…Over the recent years, alternative techniques, such as computer tomography (CT) and magnetic resonance (MR) imaging, have become more frequently accepted in the diagnosis of ovarian torsion, particularly in subacute cases (4)(5)(6). Existing literature indicate that a number of different characteristic findings such as ovarian enlargement, twisted pedicle, ovarian hemorrhage, abnormal ovarian enhancement, ascites, deviation of uterus to the twisted side, and thickening of the fallopian tube are associated with ovarian torsion (6)(7)(8)(9). Our literature search did not unearth any previous studies that assessed the diagnostic performance of preoperative MR imaging for the diagnosis of ovarian torsion.…”

Laparoscopic management of adnexal torsion

“…Clinically ovarian torsion present with non specific symptoms that include nausea, vomiting and lower abdominal pain. The torsion can be complete, leading to haemorrhagic necrosis and loss of the ovary 9 . It can also be insidious leading to a large ovarian oedema due to the increase in capillary hydrostatic pressure 10 .…”

Imaging in gynecology

“…Even though there are many studies describing features typical of adnexal torsion at ultrasound examination [145][146][147][148][149][150], CT and MRI [151,152], there is only one study reporting data that enables calculation of sensitivity and specificity with regard to adnexal torsion: in a study of 65 women with clinical suspicion of adnexal torsion, abnormal color Doppler findings in an adnexal mass predicted torsion (n =15) with a sensitivity of 100% and a specificity of 98% [153].…”