Computed Tomography and Magnetic Resonance Venography in Diagnostics of Non-Thrombotic Iliac Vein Obstruction

Objective. To analyze the incidence of non-thrombotic iliac vein obstruction (NIVO) among patients with symptomatic and asymptomatic pelvic venous disorders (PeVD) using CT and MR venography; to compare their diagnostic capabilities and to determine the relationship between severity of iliac vein obstruction and symptoms of PeVD. Material and methods. A single-center crossover study enrolled 123 symptomatic and asymptomatic patients with NIVO. After clinical examination and Doppler ultrasound of pelvic and retroperitoneal veins, all patients underwent CT and MR venography. We assessed iliac and pelvic veins, as well as the relationship between narrowing of iliac veins and PeVD symptoms. Results. The incidence of left-sided NIVO among patients with PeVD was 48%. Symptomatic forms of disease were identified in 35.2% of women, asymptomatic — in 12.9% of cases. CT and MR venography revealed narrowing of the left common iliac vein > 50% in 47.8% of symptomatic and 45.5% of asymptomatic patients (p=0.79). Diagnostic capabilities of CT and MR venography in identifying NIVO and determining severity of vascular narrowing have no significant differences. No correlation was found between narrowing of the left common iliac vein and PeVD symptoms (r=0.28). A strong association was found between moderate-to-severe reflux in pelvic veins and PeVD symptoms (r=0.85). Conclusions. CT and MR venography is effective for detecting NIVO and determining severity of iliac vein stenosis. Meanwhile, they do not allow to assess impact of iliac vein stenosis on pelvic venous hemodynamics, state of pelvic veins and symptoms of disease.