The inability of venous occlusion air plethysmography to identify patients who will benefit from stenting of deep venous obstruction

Background The aim of this study was to assess whether venous occlusion plethysmography can be used to identify venous obstruction and predict clinical success of stenting. Method Receiver operated characteristic curves were used to determine the ability of venous occlusion plethysmography to discriminate between the presence and absence of obstruction, measured by duplex ultrasound and magnetic resonance venography, and to discriminate between successful and non-successful stenting, measured by VEINES-QOL/Sym. Result Two hundred thirty-seven limbs in 196 patients were included. Areas under the curve for post-thrombotic obstruction were one-second outflow volume 0.71, total venous volume 0.69 and outflow fraction 0.59. Stenting was performed in 45 limbs of 39 patients. Areas under the curve for identifying patients with successful treatment at one year after stenting were 0.57, 0.54 and 0.63, respectively. Conclusion Venous occlusion plethysmography cannot be used to identify venous obstruction proximal to the femoral confluence or to distinguish which patients will benefit from treatment.

A comparison of magnetic resonance venography findings and venous occlusion plethysmography variables in postthrombotic syndrome

Objective The relation between venous morphology and venous function in postthrombotic syndrome is poorly understood. The aim of this study was to compare obstruction and collateralization as seen with magnetic resonance venography with variables of venous occlusion plethysmography in patients with postthrombotic syndrome. Methods Medical records, magnetic resonance venography and venous occlusion plethysmography data were analyzed in 28 patients (33 legs). Magnetic resonance venography images were scored for degree of obstruction and collateralization in segments of pelvic and abdominal veins and correlated to venous occlusion plethysmography data. Results Obstruction of the inferior vena cava correlated with an overall increase of collaterals ( p < 0.001). The summary scores of collaterals or obstructions did not correlate with venous occlusion plethysmography variables. Relative expelled volume at 4 s correlated inversely with obstruction of the inferior vena cava ( p = 0.045) and vertebral collateralization ( p = 0.033). Conclusions Modest correlations were found between magnetic resonance venography scores and venous occlusion plethysmography variables. Prospective studies with refined scoring and magnetic resonance venography techniques may increase our knowledge further.