Ovarian and tubal torsion: imaging findings on US, CT, and MRI

Abstract

Accurate diagnosis of adnexal torsion is often challenging, as clinical presentation is nonspecific and the differential for pelvic pain is broad. However, prompt diagnosis and treatment is critical to good clinical outcomes and preservation of the ovary and/or fallopian tube. Ultrasound (US) imaging is most frequently used to assess torsion. However, as computed tomography (CT) utilization in the emergency setting has increased, there are times when CT is the initial imaging test. Additionally, the nonspecific clinical presentation may initially be interpreted as gastrointestinal in etiology, where CT is the preferred exam. For these reasons, it is imperative to know the findings of adnexal torsion on CT as well as US. Magnetic resonance imaging (MRI) is helpful in cases where the diagnosis remains unclear and is particularly helpful in the young or pregnant patient with equivocal sonographic findings, as it provides excellent soft tissue contrast without ionizing radiation. This article will illustrate the findings of surgically confirmed ovarian and fallopian tube torsion on US, CT, and MRI, including those in the pregnant patient. Ovarian enlargement, adnexal mass, twisting of the vascular pedicle, edematous and heterogeneous appearance of the ovary, peripheral ovarian follicles, free fluid, uterine deviation towards the side of torsion, adnexal fat stranding, tubal dilatation, and decreased adnexal enhancement will be reviewed. Familiarity with the range of imaging findings across multiple modalities is key to improving the likelihood of timely diagnosis and therefore improved clinical outcomes.

Diagnostic performance of diffusion-weighted MRI in the diagnosis of ovarian torsion: comparison of torsed and nonaffected ovaries

“…However, one disadvantage in cross-sectional imaging of pregnant women is that contrast media are not used. Other disadvantages are the requirement for sedation with the use of contrast media in child patients and the careful use of gadolinium-based contrast media in children younger than 12 months due to renal function immaturity [9]. Therefore, an advanced imaging technique is needed for definitive diagnosis of ovarian torsion.…”

“…However, the timely and correct diagnosis of ovarian torsion has a vital role in the protection of the ovaries and preserving fertility. A delayed diagnosis of ovarian torsion may cause severe morbidity, including ovarian necrosis, peritonitis, sepsis, and even death [8][9][10][11].…”

Ovarian Torsion: Can We Operate Earlier?

“…MRI and CT were useful to show decreased contrast enhancement and adnexal fat stranding but they had not enough for certain diagnosis. 10 On the other hand, in another study, the diagnostic value of initial CT was found less beneficial than initial sonography. 11 The use of Doppler flow analysis on ultrasound can help to improve diagnostic accuracy but it has a high false-negative rate.…”

Evaluating the Acute Abdomen in the Pregnant Patient

“…Ovarian hemorrhage, a frequent sequela of torsion, can be identified on MR imaging, especially using T1-weighted images where blood products are hyperintense. 42 Chiou and colleagues 43 found that the presence on MR imaging of pelvic fat infiltration, hematoma formation, and the lack of enhancement sign were highly associated with necrosis of the involved adnexa, requiring rapid surgical intervention.…”

“…Normal Doppler flow can be observed in 45% to 61% of all ovarian torsion cases. 42,43 MR imaging should be performed after inconclusive US. Asymmetric enlargement of the ovary and stromal edema are well demonstrated by MR imaging, especially using T2-weighted sequences (Fig.…”