Ovarian torsion

Background

• Ovarian torsion is the rotation of the ovary and portion of the fallopian tube on the supplying vascular pedicle. It is also referred to as adnexal torsion and tubo-ovarian torsion.
• Occurs in females of all ages
  • Most common in reproductive age adults
  • In children: most common in 9-14 yrs old
• Ovarian cysts (usually > 4cm) and neoplasms account for 94% of cases in adults. However in children they are only less common in children.
• Torsion more common on the right, sigmoid tends to stabilize the left
• In children hypermobility of the ovary many be the primary cause of torsion.
• Dual blood supply from oarian and uterine arteries.

Pathophysiology

Torsion occurs from either of the two causes:

1. Hypermobility of the ovary
2. Adnexal mass

• Cysts greater than 4cm more likely to torse
• 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 (59%)
  • Can be intermittent
  • Commonly occurs simultaneously with vomiting
• Fever (<2%)

Differential Diagnosis

RLQ Pain

• GI
  • Appendicitis
    • Perforated appendicitis
  • Peritonitis
  • Crohn's disease (terminal ileitis)
  • Diverticulitis (cecal, Asian patients)
  • Inguinal hernia
  • Mesenteric ischemia
  • Ischemic colitis
  • Meckel's diverticulum
  • Neutropenic enterocolitis (typhlitis)
• GU
  • Ectopic
  • Endometriosis
  • Kidney stone
  • Mittelschmerz
  • Ovarian cyst
  • Ovarian torsion
  • PID
  • Pyelonephritis
• Other
  • Abdominal aortic aneurysm
  • Epiploic appendagitis
  • Mesenteric lymphadenitis
  • Herpes zoster
  • Psoas abscess
  • Testicular torsion

LLQ Pain

• Diverticulitis
• Kidney stone
• UTI
• Pyelonephritis
• Ectopic pregnancy
• Infectious colitis
• Inflammatory bowel disease (Crohn's Disease, Ulcerative Colitis)
• Inguinal hernia
• Mesenteric ischemia
• Epiploic appendagitis
• Mittelschmerz
• Ovarian cyst
• Ovarian torsion
• PID
• Psoas abscess
• Testicular torsion
• Appendicitis
• Abdominal aortic aneurysm
• Herpes zoster
• Endometriosis
• Colon cancer
• Irritable bowel syndrome
• Small bowel obstruction

Diagnosis

Although the gold standard is direct visualization in the operating room ultrasound is generally the first diagnostic test performed. The ovary can torse intermittently so high clinical suspicion is need, especially in the setting of a negative ultrasound.

Pelvic exam

• May not have Adnexal TTP or adnexal mass.

Ultrasound

Findings suggestive of torsion may include:

• Diminished or absent blood flow in the ovarian vessels
  • 2/3 of patients with ovarian torsion have had normal blood flow.
• Ovarian mass > 3 cm may be clue
• Enlarged ovarian volume
  • MC finding
• 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

CT Abd/Pelvis

• CT will not diagnose torsion
• CT may be used to r/o other possible causes of lower abdominal pain; also exclude presence of pelvic mass

Treatment

• Emergent OB/GYN consult in ED
  • May consider if high suspicion despite negative US.
• Surgical detorsion is required to prevent ovarian necrosis. If the ovary become necrotic there is a high risk of infection.
  • Salvage rate may be high even if prolonged time

See Also

• Abdominal pain