BACKGROUND AND PURPOSE:

• Wattar et al. (BJOG, 2020) compared the accuracy of ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI) for diagnosing adnexal torsion

METHODS:

• Systematic review and meta-analysis
• Data sources
  • EMBASE, MEDLINE, Cochrane through December 2019
• Study inclusion criteria
  • Female patients (pediatric and adult) suspected of adnexal torsion
  • Accuracy of ‘index test’ (any imaging modality) vs ‘reference standard’ (surgical diagnosis and/or standard clinical/radiological follow-up)
• Study design
  • 2×2 tables constructed for each imaging modality
  • Sensitivity, specificity and likelihood ratios for positive and negative test results were calculated using with 95% CIs
  • If ≥4 studies available: Random effect model used
  • If <4 studies available: Univariate model used

RESULTS:

• 18 studies (15 included in meta-analysis) | 1654 women | 665 cases of adnexal torsion
• Ultrasound (n = 12; 1187 women)
  • Pooled sensitivity: 0.79 (95% CI, 0.63 to 0.92)
  • Specificity: 0.76 (95% CI, 0.54 to 0.93)
  • Negative likelihood ratio: 0.29 (95% CI, 0.13 to 0.66)
  • Positive likelihood ratio: 4.35 (95% CI, 2.03 to 9.32)
• Doppler with ultrasound (n = 7; 845 women)
  • Sensitivity: 0.80 (95% CI, 0.67 to 0.93)
  • Specificity: 0.88 (95% CI, 0.72 to 1.00)
• MRI (n = 3; 99 women)
  • Sensitivity: 0.81 (95% CI, 0.63 to 0.91)
  • Specificity: 0.91 (95% CI, 0.80 to 0.96)
• CT (n = 3; 232 women)
  • Meta-analysis for CT was not possible due to small study ‘n’  
  • Sensitivity range: 0.74 to 0.95
  • Specificity range: 0.80 to 0.90

CONCLUSION:

• Ultrasound performs well as a first line diagnostic tool for suspected adnexal torsion
• The authors suggest that MRI may offer improved specificity, which could be helpful in a setting where the diagnosis is unclear, but there is a high index of suspicion | However, more evidence is necessary
• The authors state

Currently, care for affected women is heterogeneous, often tailored by the attending clinician and their speciality of interest (emergency medicine, general surgery, urology, gynaecology) increasing the chance of delayed diagnosis and treatment

Developing and evaluating standardised care pathways with rapid access to imaging services is needed to improve the long‐term outcomes of women with AT

Learn More – Primary Sources:

Accuracy of imaging modalities for adnexal torsion: a systematic review and meta‐analysis

Related ObG Topics:

Diagnosis and Management of Adnexal Torsion in Adolescents

Is Ovarian Torsion Associated with Ligament Length?

Evaluation of the Adnexal Mass

Could Existing Ultrasound Predictive Models be Used to Better Predict Ovarian Cancer?