What are the clinical diagnostic criteria for ovarian torsion?

From the Guidelines

Diagnosing ovarian torsion clinically requires a high index of suspicion and prompt evaluation of symptoms, with a thorough gynecologic history and physical examination, followed by urgent ultrasound evaluation with transvaginal ultrasound (TVUS) being the most useful imaging modality for initial assessment, as it demonstrated a sensitivity of 83.3% for ovarian torsion 1. The diagnosis should be considered in any female patient presenting with acute onset of severe, unilateral lower abdominal or pelvic pain, particularly if it is associated with nausea and vomiting. On physical examination, look for lower quadrant tenderness with palpation, peritoneal signs, and an adnexal mass. The pain of ovarian torsion is typically sudden, severe, and may be intermittent due to partial torsion and detorsion. Additional clinical findings may include low-grade fever and leukocytosis. Some key signs of ovarian torsion on US include:

• Ovarian tissue edema, with a sensitivity of 21% and specificity of 100% 1
• Absence of intraovarian vascularity, with a sensitivity of 52% and specificity of 91% 1
• Absence of arterial flow, with a sensitivity of 76% and specificity of 99% 1
• Absence or abnormal venous flow, with a sensitivity of 100% and specificity of 97% 1 A unilaterally enlarged ovary with central afollicular stroma and multiple uniform 8 to 12 mm peripheral follicles can also be indicative of torsion, found in up to 74% of cases 1. While ultrasound with color Doppler is the preferred initial imaging study to evaluate blood flow to the ovary, the diagnosis remains primarily clinical as normal Doppler flow does not exclude torsion, as a meta-analysis reported a pooled sensitivity and specificity in diagnosing adnexal torsion using Doppler US of 80% and 88% respectively 1. Clinical diagnosis should prompt urgent gynecological consultation, as surgical intervention within 8 hours of symptom onset provides the best chance for ovarian salvage, with the underlying pathophysiology involving twisting of the ovary on its vascular pedicle, leading to venous congestion, arterial compromise, and eventually ischemia and necrosis if not promptly addressed. Key risk factors to note in the patient's history include ovarian cysts, prior ovarian torsion, pregnancy, or recent fertility treatments. In cases where ultrasound findings are inconclusive, further evaluation with other imaging modalities or surgical exploration may be necessary to confirm the diagnosis and provide timely treatment.

From the Research

Clinical Diagnosis of Ovarian Torsion

To diagnose ovarian torsion clinically, several factors need to be considered, including:

• Clinical presentation: abdominal pain, nausea, and vomiting are common symptoms 2, 3
• Medical history: previous pelvic operations or enlarged ovaries may predispose to torsion of the ovary or fallopian tube 4
• Imaging findings: ultrasonography (US) and computed tomography (CT) can provide valuable information 5, 2
• Laboratory examinations: plasma d-dimer level and time from pain onset can help distinguish ovarian necrosis 2

Imaging Modalities

Different imaging modalities can be used to diagnose ovarian torsion, including:

• Ultrasonography (US): primary imaging modality, features include unilateral enlarged ovary, uniform peripheral cystic structures, and lack of arterial or venous flow 5
• Computed Tomography (CT): common features include an enlarged ovary, uterine deviation to the twisted side, and smooth wall thickening of the twisted adnexal cystic mass 5
• Doppler flow: not a useful variable to diagnose or exclude ovarian torsion, as normal Doppler flow does not necessarily exclude an ovarian torsion 6

Diagnostic Criteria

To increase the accuracy of diagnosis, it is necessary to integrate clinical presentation and the findings of imaging and laboratory examinations 2. The presence of ovarian cysts is significantly associated with torsion 6. A clinical diagnosis of ovarian torsion requires consideration of many factors, especially patient presentation and exclusion of other non-gynaecological pathologies 6.