Usefulness of non-contrast-enhanced magnetic resonance imaging prior to venous interventions

Introduction
The number of venous interventions continues to rise. The outcome of venous procedures is related to appropriate stent selection and implantation.

Aim
To compare the usefulness of magnetic resonance imaging (MRI) and intravascular ultrasound (IVUS) in the determination of target vein section area (VSA) as techniques for selecting an appropriate diameter for a venous stent.

Material and methods
VSAs of iliac and common femoral veins obtained in contrast-enhanced MRI (CE-MRI) and non-contrast-enhanced MRI (NCE-MRI) were calculated for 18 consecutive patients with post-thrombotic syndrome (PTS), and VSAs obtained using IVUS were calculated for 15 of these PTS patients.

Results
The differences in iliac and common femoral vein VSAs obtained using CE-MRI and NCE-MRI were small and not clinically significant. VSAs of vessels obtained using CE-MRI and NCE-MRI correlated significantly with each other, with R values in the range 0.87–0.97 and p-values < 0.001. However, no significant relationships were found between section areas measured using MRI and IVUS and the differences in measurements was, on average, to 60%.

Conclusions
CE magnetic resonance venography can be replaced by Dixon-based NCE-MRI in the preoperative evaluation of patients with PTS who qualify for venous intervention. However, CE-MRI and NCE-MRI performed for ipsilateral and contralateral extremities are not sufficient for appropriate venous stent selection, and IVUS remains a necessary tool in determining venous intervention in iliac veins.