Whirlpool sign (ovarian torsion)

The whirlpool sign or whirl sign of ovarian torsion is characterized by the appearances of a twisted ovarian pedicle seen on US or even on CT.

Terminology

The term whirlpool sign is used in other contexts: see whirlpool sign (disambiguation).

Radiographic features

It appears as twisting of the thickened vascular pedicle of the enlarged ovary. It can be detected on ultrasound confirming the diagnosis along with the other suggestive imaging features and clinical presentation . On MRI, it is best demonstrated on axial T2 and T1 C+ fat sat sequences .