Ovarian Torsion

Overview

Definition

Ovarian torsion is the twisting of the ovaries along their axis. Ovarian torsion may or may not include the fallopian tubes and it if does, it is termed adnexal torsion.

Anatomy

• The ovaries are paired glandular organs found within the lesser pelvis. 
• Supported by the suspensory ligament of the ovary and the utero-ovarian ligament:
  • The suspensory ligament of the ovary, also known as the infundibulopelvic ligament, attaches the ovary to the lateral wall of the inner surface of the pelvis.
  • The utero-ovarian ligament, also known as just the ovarian ligament, attaches the ovary medially to the uterus. 
• The ovaries have a dual blood supply, receiving blood from the ovarian and the uterine blood vessels.
• The suspensory ligament of the ovary contains the ovarian artery.
• The utero-ovarian ligament is responsible for preventing ovarian torsion. It also contains branches of the uterine artery to supply the ovary.

Epidemiology

• More common in women of reproductive age because of the regular formation of corpus luteum cysts. 
  • Corpus luteum cysts are a normal part of the menstrual cycle and disappear in a span of 3–4 weeks.
  • These cysts usually contain blood and measure about 10 cm.
  • The cysts can twist upon the ovaries, leading to torsion.
• More commonly affects women with ovaries > 5 cm
• Frequently associated with benign ovarian tumors and cysts
• Torsion of the left ovary is less frequent because it is supported by the sigmoid colon.
• Patients undergoing treatment for infertility are particularly susceptible to torsion because of the enlarged size of the ovaries.

Risk factors

• Ovarian masses (severity of the torsion is determined by the size of the mass) 
• Pregnancy 
• Congenital abnormalities (e.g., elongation of fallopian tubes)
• A history of pelvic surgery (due to adhesions)

Pathogenesis

Ovarian or adnexal torsion involves the following sequence of events:

1. Twisting along the ovarian axis (suspensory ligament or utero-ovarian ligament)
2. Compression/blockage of the venous and lymphatic drainage from the ovaries
3. Local edema of the ovary, fallopian tubes, and supportive ligaments
4. Compression/blockage of the arterial supply of the ovaries
5. Ischemia, followed by necrosis of the ovarian tissue
6. Local hemorrhage from friable necrotic tissue

Clinical Presentation

• The most common symptom is sudden, severe lower abdominal pain that may radiate to the rest of the abdomen, back, and flank. 
• Nausea and vomiting:
  • Common
  • May be continuous or appear in waves 
• Fever can be seen in cases in which the ovary is undergoing necrosis or rupture. 
• Abnormal vaginal bleeding and discharge might be present if associated with rupture or an abscess. 
• Physical examination of the patient must be performed to look for:
  • Abdominal guarding
  • Localized pain upon palpation
  • Cervical motion tenderness
  • Unilateral tender adnexal mass

Diagnosis and Management

Adnexal torsion is suspected based on typical symptoms, supported by imaging with transvaginal ultrasonography or color Doppler ultrasonography, and confirmed during immediate exploratory surgery.

Laboratory tests

• CBC to look for anemia and leukocytosis:
  • Anemia and leukocytosis are seen in cases of hemorrhage.
  • Leukocytosis is seen in cases of rupture.
• hCG levels are important to determine or rule out pregnancy, as pregnancy is a major risk factor for ovarian torsion.

Imaging

• Ultrasonography along with pelvic Doppler can also be performed. 
  • The ultrasound will show an asymmetrically enlarged ovary. 
  • The Doppler findings might be inconsistent but can help in the evaluation of the ovarian blood supply. 
  • Decreased venous blood flow points toward ovarian torsion.  
  • Free fluid might be present in the pelvic cavity. 
• CT can confirm the condition and rule out other abdominal conditions, such as appendicitis.

Surgical confirmation

Laparoscopy/laparotomy is the gold standard for the diagnosis of ovarian torsion, as the twisted ovary can be directly visualized by the surgeon. 

Management

• Laparoscopy is the go-to treatment for ovarian torsion. 
• Laparotomy must be performed if suspicion of malignancy arises during the initial surgery.
• Prompt and early resolution of the torsion must be attempted in women of reproductive age, as this might preserve fertility. The viability of the ovary is evaluated by the surgeon. 
• Cystectomy can be performed if a benign cyst is present. 
• In postmenopausal women or patients with malignant tumors, salpingo-oophorectomy is preferred.

Differental Diagnosis

• Ectopic pregnancy: implantation of the fertilized embryo outside the uterine cavity, usually in a fallopian tube. Ectopic pregnancy presents with sudden and severe abdominal pain. When rupture occurs, ectopic pregnancy can present with fever, sepsis, and peritonitis. Usually, there is a history of a missed menstrual period. Findings include a positive pregnancy test and pain with cervical manipulation (pelvic exam). Diagnosis is confirmed with pelvic ultrasonography.
• Ruptured ovarian cyst: fluid-filled sac within an ovary or on its surface, which can form as a result of ovulation. Rupture of a cyst can cause severe pain and internal bleeding. Diagnostic findings may include an adnexal mass and free fluid within the pelvis on ultrasonography, along with a negative pregnancy test. Management includes watchful waiting for uncomplicated cysts and surgery for cysts associated with hemorrhage.
• Pelvic inflammatory disease (PID): STI involving internal reproductive organs, usually in a young adult woman. This disease presents with lower abdominal pain (mostly bilateral), fever, and vaginal discharge. Diagnosis is established with a pelvic exam and ultrasonography.
• Appendicitis: acute inflammation of the vermiform appendix and the most common abdominal surgical emergency globally. Characteristic features of appendicitis include periumbilical abdominal pain that migrates to the right lower quadrant, fever, anorexia, nausea, and vomiting. The diagnosis can frequently be established clinically, but CT is used in cases of uncertainty. The standard treatment is an appendectomy, but localized perforations are frequently managed nonoperatively with antibiotics.
• Diverticulitis: inflammation of colonic diverticula. Diverticulitis is usually left-sided, but right-sided presentation can also occur, especially in young patients and in Asian populations. Patients present with RLQ pain, fever, and change in bowel habits. Diagnosis is made by CT.
• Urinary tract infection: bacterial infection of the urinary tract in the form of cystitis (bladder infection) or acute pyelonephritis (kidney involvement). Urinary tract infection presents with suprapubic pain and dysuria (cystitis) or costovertebral angle tenderness and fever (pyelonephritis). Diagnosis is made by urinalysis and CT.