Adnexal torsion (ovarian torsion)

Definition

Ovarian Torsion

• Symptomatology: Typical is sudden, severe, unilateral pain with nausea and vomiting, often wave-like.
• Ultrasound: On ultrasound, the ovary is enlarged and oedematous because arterial inflow is preserved longer than venous outflow.
• Doppler ultrasound: Doppler is of little help because preserved arterial flow does not exclude a torsion.

• In ovarian torsion the ovary twists on its supporting ligaments (infundibulopelvic and utero-ovarian ligaments); when the fallopian tube twists with it, the term adnexal torsion is used.

Aetiopathogenesis

Pathogenesis and risk factors

• First, venous and lymphatic outflow is compromised, with oedema, congestion and enlargement of the ovary; if torsion persists, ischaemia and haemorrhagic infarction follow.
• In women of reproductive age an underlying mass, usually larger than 5 cm, is present in 50–90%, most commonly a mature cystic teratoma.
• Endometriomas and malignancies cause torsion only occasionally because of fixation to adjacent structures.

Clinical features

• Typical is abrupt-onset lower abdominal pain radiating to the flank or groin with adnexal tenderness; often, however, the picture is non-specific with intermittent pain, low-grade fever, nausea and vomiting.
• Recurrent attacks may reflect episodes of torsion and detorsion; if unrecognised, necrosis, loss of the ovary and infertility may follow.

Diagnosis

• Ultrasound is the primary imaging method; because of the dual blood supply, colour Doppler may still show arterial flow, which does not exclude torsion.
• CT shows a unilaterally enlarged ovary, often displaced to the midline, with peripherally displaced follicles, a spirally twisted pedicle, free fluid and inflammatory fat stranding.

Keep learning in the app

Further reading (selection)

1. StatPearls: Ovarian Torsion
2. DocCheck Flexikon, Ovarialtorsion

Cross-references