Ovarian torsion

Background

Arteries of the female reproductive tract: uterine artery, ovarian artery and vaginal arteries. Ovary and ovarian artery visible in upper right.
Female pelvic anatomy.
  • Ovarian torsion is the rotation of the ovary and portion of the fallopian tube on the supplying vascular pedicle
  • Referred to as adnexal torsion and tubo-ovarian torsion
  • Occurs in females of all ages
    • Most common in reproductive age adults
    • In children, it is most common in 9-14 years of age
    • Risk factors:
      • Ovarian mass
      • Fertility treatments
  • Ovarian cysts (usually > 4 cm) and neoplasms account for 94% of cases in adults[1]
  • Torsion more common on the right, as the sigmoid colon tends to stabilize the left
  • In children, hypermobility of the ovary many be the primary cause of torsion
  • Dual blood supply from ovarian and uterine arteries

Pathophysiology

Torsion occurs from either of two causes:

  1. Hypermobility of the ovary
  2. Adnexal mass
  • Cysts greater than 4 cm are more likely to torse[2]
  • Absence of ovarian Doppler flow is highly specific for torsion, but normal Doppler flow does not completely exclude torsion

Clinical Features

  • Nausea/vomiting (70%)
  • Sudden and sharp pain in the lower abdomen (50%)[3]
    • Can be intermittent and insiduous, especially in those with history of cysts, PCOS[4]
    • Commonly occurs simultaneously with vomiting
    • May occur for days to months intermittently before diagnosis is made[5]
  • Up to 30% have no tenderness on bimanual exam[6]
  • Most adults with ovarian torsion have abnormal or enlarged ovaries that serves as lead point for torsion, but torsion is more likely to occur in normal sized ovaries in pediatrics[7]
    • More than 50% of cases have no palpable adnexal mass[8]
  • Fever (<2%)
  • Up to 20% of cases seen in pregnant women, with most in the 1st trimester and/or received fertility treatments[9]

Differential Diagnosis

Acute Pelvic Pain

Differential diagnosis of acute pelvic pain

Gynecologic/Obstetric

Genitourinary

Gastrointestinal

Musculoskeletal

Vascular

RLQ Pain

LLQ Pain

Evaluation

Gray-scale (A) and power Doppler (B) sonograms show the swirling of the ovarian vascular pedicle, the “whirlpool sign,” in a case of ovarian torsion.
Contrast-enhanced CT axial image shows thickened right adnexa (thick arrow) interposed between the cystic lesion (thin arrow) and uterus (Ut) which raised suspicion of adnexal torsion.[11]
Sagittal MR image showing "whirlpool appearance" of the right adnexa (thick arrow) suggestive of ovarian torsion. Right ovarian cystic mass is also seen (thin arrow). MRI is not typically first line imaging for ovarian torsion.[12]

Doppler Ultrasound

Findings suggestive of torsion may include:

  • Diminished or absent blood flow in the ovarian vessels[13]
    • 2/3 of patients with ovarian torsion have had normal blood flow
    • Venous and lymphatic obstruction occurs before arterial disruption, especially early in disease process[14]
    • Abnormal blood flow, whether venous or arterial, is ~85% sensitive, ~37% specific when not combined with below findings[15]
  • Enlarged ovarian volume
    • MC finding
    • A maximum ovarian diameter (MOD) < 3cm in a postmenarchal patient is unlikely to represent ovarian torsion[16]
  • 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[13]

CT Abd/Pelvis

  • CT has a low sensitivity for torsion
    • Examine for asymmetric ovarian enlargement, which warrants a pelvic US if concerning symptoms exist[17]
  • CT may be used to rule out other possible causes of lower abdominal pain; also exclude presence of pelvic mass

Management

  • Emergent OB/GYN consult in ED
    • Consider if high suspicion exists even after equivocal US
  • Surgical detorsion is required to prevent ovarian necrosis
    • If the ovary becomes necrotic, there is a high risk of infection
    • Salvage rate may be high even if time is prolonged beyond several hours of symptoms[18]

See Also

External Links

References

  1. ↑ Amirbekian S et al. Ultrasound Evaluation of Pelvic Pain. Radiol. Clin. North Am. 2014;52 (6): 1215-1235
  2. ↑ M.L. Brandt et al. Surgical indications in antenatally diagnosed ovarian cysts J Pediatr Surg, 26 (1991), pp. 276–282
  3. ↑ Houry, D. and Abbott, J.T. Ovarian torsion: a fifteen-year review. Ann Emerg Med. 2001; 38: 156–159.
  4. ↑ Damigos, E., Johns, J., and Ross, J. An update on the diagnosis and management of ovarian torsion. Obstet Gynaecol. 2012; 14: 229–236.
  5. ↑ Sasaki, K.J. and Miller, C.E. Adnexal torsion: review of the literature. J Minim Invasive Gynecol. 2014; 21: 196–202.
  6. ↑ Houry, D. and Abbott, J.T. Ovarian torsion: a fifteen-year review. Ann Emerg Med. 2001; 38: 156–159.
  7. ↑ Anders, J.F. and Powell, E.C. Urgency and evaluation and outcome of acute ovarian torsion in pediatric patients. Arch Pediatr Adolesc Med. 2005; 159: 532–535.
  8. ↑ Houry, D. and Abbott, J.T. Ovarian torsion: a fifteen-year review. Ann Emerg Med. 2001; 38: 156–159.
  9. ↑ Albayram, F. and Hamper, U.M. Ovarian and adnexal torsion: spectrum of sonographic findings with pathologic correlation. J Ultrasound Med. 2001; 20: 1083–1089.
  10. ↑ Norris DL, Young JD. UTI. EM Clin N Am. 2008; 26:413-30.
  11. ↑ Ghonge NP, Lall C, Aggarwal B, Bhargava P - Radiology case reports (2015). The MRI whirlpool sign in the diagnosis of ovarian torsion.
  12. ↑ Ghonge NP, Lall C, Aggarwal B, Bhargava P - Radiology case reports (2015). The MRI whirlpool sign in the diagnosis of ovarian torsion.
  13. ↑ 13.0 13.1 Lee EJ et-al. Diagnosis of ovarian torsion with color Doppler sonography: depiction of twisted vascular pedicle. J Ultrasound Med. 1998;17 (2): 83-9.
  14. ↑ Cicchiello, L.A., Hamper, U.M., and Scoutt, L.M. Ultrasound evaluation of gynecologic causes of pelvic pain. Ultrasound Clin. 2010; 38: 85–114.
  15. ↑ Cicchiello, L.A., Hamper, U.M., and Scoutt, L.M. Ultrasound evaluation of gynecologic causes of pelvic pain. Ultrasound Clin. 2010; 38: 85–114.
  16. ↑ Budhram G, Elia T, Dan J, et al. A Case-Control Study of Sonographic Maximum Ovarian Diameter as a Predictor of Ovarian Torsion in Emergency Department Females With Pelvic Pain. Acad Emerg Med. 2019;26(2):152-159.
  17. ↑ Lourenco, A.P., Swenson, D., Tubbs, R.J. et al. Ovarian and tubal torsion: imaging findings on US, CT and MRI. Emerg Radiol. 2014; 21: 179–187.
  18. ↑ Anders JF, Powell EC. Urgency of evaluation and outcome of acute ovarian torsion in pediatric patients. Arch Pediatr Adolesc Med. 2005;159:532–535
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