Reproductive · Gynecology
The facts most likely to be tested
Functional ovarian cysts are the most common cause of adnexal masses in reproductive-age women and typically resolve spontaneously within two menstrual cycles.
Follicular cysts result from the failure of a mature follicle to rupture, while corpus luteum cysts occur when the corpus luteum fails to regress and continues to produce progesterone.
Ovarian torsion presents as sudden-onset, severe, unilateral pelvic pain often associated with nausea and vomiting, requiring urgent surgical evaluation to prevent ovarian necrosis.
Transvaginal ultrasound is the first-line imaging modality for evaluating an adnexal mass to characterize the cyst as simple or complex.
Simple cysts are characterized by thin walls, lack of internal septations, and absence of solid components, which generally indicates a benign etiology.
Complex cysts with thick septations, solid components, or internal vascularity on Doppler ultrasound raise high suspicion for malignancy and require further investigation.
Ruptured ovarian cysts typically present with acute, sharp pelvic pain following strenuous activity or intercourse and are managed conservatively with analgesia if the patient is hemodynamically stable.
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A 24-year-old female presents to the emergency department with sudden-onset, sharp right-sided pelvic pain that began while playing soccer. She reports associated nausea and one episode of emesis. On physical exam, she has right adnexal tenderness and guarding. Her vital signs are stable, and a urine pregnancy test is negative. Transvaginal ultrasound reveals an enlarged right ovary with decreased venous flow and a 4 cm cystic structure.
What is the most appropriate next step in management?
Urgent surgical exploration (laparoscopy)
The patient's presentation of sudden, severe pain with nausea and ultrasound findings of decreased venous flow is classic for ovarian torsion, a surgical emergency tested in the 'bets' regarding torsion.
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High yield triage
Etiology / Epidemiology
Functional cysts are common in reproductive-age women due to normal hormonal fluctuations.
Clinical Manifestations
Often asymptomatic; presents with unilateral pelvic pain or adnexal tenderness.
Diagnosis
Transvaginal ultrasound is the gold standard; cysts >10 cm require surgical evaluation.
Treatment
Most resolve spontaneously; oral contraceptives prevent recurrence, do not use if torsion suspected.
Prognosis
Risk of ovarian torsion is highest with cysts >5 cm; malignancy risk increases with age.
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Epidemiology & Etiology
Functional cysts (follicular and corpus luteum) are the most common ovarian masses in premenopausal women. Follicular cysts result from failure of follicle rupture, while corpus luteum cysts occur when the corpus luteum fails to involute. Risk factors include ovulation induction therapy and hormonal imbalances.
Pertinent Anatomy
Cysts arise from the ovarian cortex. The proximity of the ovary to the adnexa and fallopian tubes explains why large cysts cause referred pain or mechanical obstruction.
Pathophysiology
Follicular cysts develop when a dominant follicle fails to rupture during the mid-cycle surge of luteinizing hormone. Corpus luteum cysts occur post-ovulation when the corpus luteum becomes hemorrhagic or cystic. Persistent hormonal stimulation leads to continued growth and potential rupture or hemorrhage.
Clinical Manifestations
Patients typically report dull, aching pelvic pain or dyspareunia. Sudden, severe, unilateral pain suggests ovarian torsion or rupture. Physical exam reveals a mobile, adnexal mass; peritoneal signs indicate hemoperitoneum from rupture.
Diagnosis
Transvaginal ultrasound is the diagnostic modality of choice. Simple cysts appear as anechoic, thin-walled, unilocular structures. Cysts >10 cm or those with complex features (septations, solid components) require CA-125 testing and surgical consultation to rule out malignancy.
Treatment
Observation is the standard for asymptomatic, simple cysts <5 cm. Oral contraceptives suppress gonadotropins to prevent new cyst formation. Surgical intervention (cystectomy or oophorectomy) is mandatory for suspected torsion, persistent pain, or complex features suggestive of neoplasm.
Prognosis
Most functional cysts resolve within 2-3 menstrual cycles. Ovarian torsion is the most feared acute complication, requiring immediate detorsion to preserve fertility. Postmenopausal women with new cysts require aggressive workup for ovarian cancer.
Differential Diagnosis
Ectopic pregnancy: positive beta-hCG
Ovarian torsion: sudden onset, severe pain, nausea
Appendicitis: RLQ pain, fever, leukocytosis
Endometrioma: chocolate cyst, chronic pelvic pain
Pelvic inflammatory disease: cervical motion tenderness