Reproductive · Gynecologic Emergencies
The facts most likely to be tested
The most significant risk factor for ovarian torsion is the presence of an ovarian mass or cyst greater than 5 cm.
Patients typically present with the sudden onset of unilateral, sharp, colicky pelvic pain often associated with nausea and vomiting.
The gold standard for diagnosis is surgical visualization via laparoscopy, though pelvic ultrasound with Doppler is the initial imaging modality of choice.
Doppler ultrasound findings of decreased or absent venous/arterial flow are highly specific but have low sensitivity, meaning a normal study does not rule out torsion.
The classic ultrasound finding is an enlarged ovary with peripheral displacement of follicles due to stromal edema.
Ovarian torsion is a surgical emergency requiring prompt detorsion to preserve ovarian function, especially in patients of reproductive age.
The presence of a whirlpool sign on ultrasound, representing the twisted pedicle of the ovary, is a highly specific diagnostic finding.
Vignette unlocked
A 24-year-old female presents to the emergency department with a 4-hour history of sudden-onset, severe right lower quadrant pain radiating to her back. She reports two episodes of nausea and vomiting since the pain began. Physical examination reveals right adnexal tenderness and guarding, but no rebound tenderness. A pelvic ultrasound shows a right-sided ovarian mass measuring 6 cm with peripheral displacement of follicles and absent venous flow on Doppler imaging.
What is the most appropriate next step in management?
Urgent surgical detorsion
The patient's presentation of sudden, severe unilateral pain with an adnexal mass and absent Doppler flow is classic for ovarian torsion, which requires immediate surgical intervention to prevent ovarian necrosis.
Full handout
High yield triage
Etiology / Epidemiology
Occurs primarily in reproductive-age women with ovarian masses >5cm. Ovarian enlargement is the primary risk factor.
Clinical Manifestations
Presents with sudden-onset, severe unilateral pelvic pain often associated with nausea and vomiting.
Diagnosis
The transvaginal ultrasound with Doppler is the gold standard; look for absent venous flow.
Treatment
Requires emergent surgical detorsion and oophoropexy; avoid delayed intervention to prevent necrosis.
Prognosis
Early diagnosis preserves fertility; ovarian necrosis is the primary long-term complication.
Full handout
Epidemiology & Etiology
Most common in reproductive-age women, frequently associated with functional cysts or benign neoplasms like mature cystic teratomas. Ovarian enlargement (>5cm) creates a pendulum effect, increasing the risk of rotation around the pedicle. Pregnancy is a significant risk factor due to corpus luteum enlargement.
Pertinent Anatomy
The ovary is suspended by the infundibulopelvic ligament and the ovarian ligament. Torsion involves the twisting of these vascular pedicles, which contain the ovarian artery and vein. Compromise of these vessels leads to venous congestion followed by arterial occlusion.
Pathophysiology
Twisting of the adnexa leads to venous and lymphatic obstruction, causing ovarian edema and congestion. As interstitial pressure rises, arterial inflow is eventually compromised, leading to ischemic necrosis. The process is a surgical emergency as prolonged ischemia results in irreversible tissue loss.
Clinical Manifestations
Patients present with acute, sharp, unilateral pelvic pain that is often intermittent initially. Nausea and vomiting are classic associated symptoms, occurring in up to 70% of cases. Peritoneal signs or fever may indicate advanced necrosis or secondary infection.
Diagnosis
The transvaginal ultrasound with Doppler is the diagnostic study of choice. Key findings include an enlarged ovary with peripheral follicle displacement and absent venous/arterial flow on Doppler. Note that the presence of flow does not definitively rule out torsion due to the dual blood supply from the uterine artery.
Treatment
Management is emergent surgical detorsion via laparoscopy. If the ovary appears viable, detorsion is performed; if necrotic, an oophorectomy is required. Do not perform needle aspiration of cysts during surgery due to the risk of malignancy seeding.
Prognosis
Timely intervention is critical to preserve ovarian function and future fertility. Ovarian necrosis is the most significant complication, necessitating removal. Post-operative monitoring for signs of sepsis or hemorrhage is required.
Differential Diagnosis
Ectopic pregnancy: positive beta-hCG
Ruptured ovarian cyst: sudden onset but usually no nausea/vomiting
Appendicitis: migratory pain to RLQ
Pelvic inflammatory disease: bilateral pain and cervical motion tenderness
Nephrolithiasis: hematuria and flank radiation