Accuracy of transvaginal duplex ultrasound compared to catheter venography for the identification of pelvic vein incompetence

ObjectiveChronic pelvic pain (CPP) is a debilitating condition affecting a quarter of premenopausal women and has been associated with pelvic vein incompetence (PVI). Catheter venography (CV) is the standard investigation, although transvaginal duplex (TVDU) ultrasound has emerged as a promising alternative. The accuracy of TVDU compared to CV is undefined and the optimal reflux time measured by TVDU to diagnose PVI is unknown. This study aimed to establish the diagnostic accuracy of TVDU in those with suspected PVI.MethodsThis cohort study included women enrolled into a randomised controlled trial comparing pelvic vein embolisation to no treatment, who underwent both TVDU and CV. Three consultant vascular interventional radiologists, blinded to TVDU results, independently reviewed catheter venograms. Reflux in bilateral ovarian and internal iliac veins was reported as a binary outcome. Pelvic reflux times, in both supine and semi-standing positions, were retrieved from TVDU reports. Diagnostic accuracy of TVDU was assessed using CV as the comparator. Sensitivity, specificity and area under the ROC curve (AUC) were calculated.Results124 pelvic veins were analysed in 31 women. For a diagnostic reflux time threshold of 500 ms, TVDU had a sensitivity of 64% and specificity of 78% (AUI 0.71,95%CI 0.66-0.76). For a threshold of 700 ms, TVDU had a sensitivity of 74% and a specificity of 78% (AUI 0.76,95%CI 0.71-0.80). For a threshold of 700 ms, TVDU performed semi-standing had a sensitivity of 78% and specificity of 78% (AUC of 0.78,95%CI 0.72-0.84) as compared to TVDU performed supine which had a sensitivity of 70% and specificity of 78% (AUC 0.74,95%CI 0.67-0.80).ConclusionsTVDU demonstrates good diagnostic accuracy for PVI using a 700 ms reflux time threshold. Performing the test in a semi-standing position optimises accuracy. TVDU has potential as a diagnostic tool and may eliminate unnecessary invasive investigations, thus preserving catheter venography for intention to treat.