Ovarian torsion is a condition where the ovary twists in relation to the surrounding connective tissue, fallopian tube and blood supply (the adnexa).
Ovarian torsion is usually due to an ovarian mass larger than 5cm, such as a cyst or a tumour. It is more likely to occur with benign tumours. It is also more likely to occur during pregnancy.
Ovarian torsion can also happen with normal ovaries in younger girls before menarche (the first period), when girls have longer infundibulopelvic ligaments that can twist more easily.
Twisting of the adnexa and blood supply to the ovary leads to ischaemia. If the torsion persists, necrosis will occur, and the function of that ovary will be lost. Therefore, ovarian torsion is an emergency, where a delay in treatment can have significant consequences. Prompt diagnosis and management is essential.
The main presenting feature is sudden onset severe unilateral pelvic pain. The pain is constant, gets progressively worse and is associated with nausea and vomiting.
The pain is not always severe, and ovarian torsion can take a milder and more prolonged course. Occasionally, the ovary can twist and untwist intermittently, causing pain that comes and goes.
On examination there will be localised tenderness. There may be a palpable mass in the pelvis, although the absence of a mass does not exclude the diagnosis.
Pelvic ultrasound is the initial investigation of choice. Transvaginal is ideal, but transabdominal can be used where transvaginal is not possible. It may show “whirlpool sign”, free fluid in pelvis and oedema of the ovary. Doppler studies may show a lack of blood flow.
The definitive diagnosis is made with laparoscopic surgery.
Patients need emergency admission under gynaecology for urgent investigation and management. Depending on the duration and severity of the illness they require laparoscopic surgery to either:
- Un-twist the ovary and fix it in place (detorsion)
- Remove the affected ovary (oophorectomy)
The decision whether to save the ovary or remove it is made during the surgery, based on a visual inspection of the ovary. Laparotomy may be required where there is a large ovarian mass or malignancy is suspected.
A delay in treating ovarian torsion can result in loss of function of that ovary. The other ovary can usually compensate, so fertility is not typically affected. Where this is the only functioning ovary, loss of function leads to infertility and menopause.
Where a necrotic ovary is not removed, it may become infected, develop an abscess and lead to sepsis. Additionally it may rupture, resulting in peritonitis and adhesions.
Last updated June 2020