[[The MRI whirlpool sign in the diagnosis of<unk> .
Ghonge NP, Lall C, Aggarwal B, Bhargava P - Radiology case reports (2015)|thumb|18-year-old female with<unk> . T2-weighted, sagittal MR image showing "whirlpool appearance" of the right adnexa (thick arrow) suggestive of<unk> . Right<unk>  cystic mass is also seen (thin arrow). MRI is not typically first line imaging for<unk> .]]
Findings suggestive of torsion may include:
Diminished or absent blood flow in the<unk>  vessels
2/3 of patients with<unk>  have had normal blood flow
Venous and lymphatic obstruction occurs before arterial disruption, especially early in disease process
Abnormal blood flow, whether venous or arterial, is ~85% sensitive, ~37% specific when not combined with below findings
Enlarged<unk>  volume
MC finding
A maximum<unk>  diameter (MOD) < 3cm in a postmenarchal patient is unlikely to represent<unk> 
Loss of echogenicity
Peripherally displaced follicles with hyperechoic central stroma
Midline ovary
Pelvic free fluid
An infarcted ovary may have a more complex appearance with cystic or hemorrhagic degeneration
Whirlpool sign of twisted vascular pedicle may be seen but rare
2/3 of patients with<unk>  have had normal blood flow
Venous and lymphatic obstruction occurs before arterial disruption, especially early in disease process
Abnormal blood flow, whether venous or arterial, is ~85% sensitive, ~37% specific when not combined with below findings
MC finding
A maximum<unk>  diameter (MOD) < 3cm in a postmenarchal patient is unlikely to represent<unk> 
CT has a low sensitivity for torsion
Examine for asymmetric<unk>  enlargement, which warrants a pelvic US if concerning symptoms exist
CT may be used to rule out other possible causes of lower abdominal pain; also exclude presence of pelvic mass
Examine for asymmetric<unk>  enlargement, which warrants a pelvic US if concerning symptoms exist
Ovarian torsion
Appendicitis
Testicular torsion
Perforated appendicitis
Tubo-ovarian abscess
Peritonitis
Epididymitis
Abdominal aortic aneurysm