From the Guidelines
Ovarian torsion typically presents with sudden onset, severe, unilateral lower abdominal or pelvic pain, and its diagnosis is often challenging due to overlapping symptoms with other conditions, making prompt diagnosis and surgical intervention crucial to preserve ovarian function. The clinical presentation of ovarian torsion can vary based on the degree of torsion, with partial torsion causing intermittent pain as the ovary twists and untwists 1. Patients may experience nausea and vomiting, low-grade fever, tachycardia, and urinary symptoms, and on physical examination, there is usually unilateral abdominal tenderness with guarding, and a palpable adnexal mass may be detected in some cases.
Some key signs of ovarian torsion on ultrasound include:
- Ovarian tissue edema with sensitivity and specificity of 21% and 100%, respectively 1
- Absence of intraovarian vascularity with sensitivity and specificity of 52% and 91%, respectively 1
- Absence of arterial flow with sensitivity and specificity of 76% and 99%, respectively 1
- Absence or abnormal venous flow with sensitivity and specificity of 100% and 97%, respectively 1
- A unilaterally enlarged ovary with central afollicular stroma and multiple uniform 8 to 12 mm peripheral follicles, found in up to 74% of cases 1
Transvaginal ultrasound with Doppler flow studies is the initial imaging modality of choice for diagnosing ovarian torsion, with a pooled sensitivity of 79% and a pooled specificity of 76% for adnexal torsion 1. However, normal blood flow does not exclude torsion as it can be intermittent or dual blood supply may be present. Prompt surgical intervention is necessary to preserve ovarian function, as prolonged ischemia leads to necrosis. Risk factors for ovarian torsion include ovarian masses, particularly those 5-10 cm, pregnancy, and prior pelvic surgery 1.
From the Research
Clinical Presentation of Ovarian Torsion
- The most common presenting symptom of ovarian torsion is abdominal pain, which occurs in 95% of patients 2, often localizing to the right lower quadrant 2.
- Nausea and vomiting are also common symptoms, occurring in 70-90% of patients 2, 3.
- The pain can be acute in onset, but it is not always sudden or severe 3.
- Patients may have symptoms for several hours or days, making the diagnosis more challenging 4.
Diagnostic Findings
- Ultrasound can assist with diagnosis, but a normal ultrasound examination cannot exclude the diagnosis 3, 4.
- Computed tomography with intravenous contrast can also assist with diagnosis 3.
- Ovarian cysts are present in 75% of patients who undergo ultrasound, and abnormal ovarian blood flow is seen in 50% of patients 2.
- Plasma d-dimer level and the time from pain onset play a critical role in distinguishing ovarian necrosis 5.
Patient Characteristics
- Ovarian torsion can occur in females of all ages, including infants, reproductive-aged women, pregnant women, and postmenopausal women 3, 4, 6.
- The majority of patients are women of reproductive age, with a mean age of 27.3 years 2.
- The incidence of ovarian torsion in the emergency department is 157.4 per 100,000 visits of women in the reproductive age group 2.