Usefulness of Direct Computed Tomography Venography in Predicting Inflow for Venous Reconstruction in Chronic Post-thrombotic Syndrome.

Abstract

The purpose of this paper is to assess the applicability of direct computed tomography venography (DCTV) in assessing dominant inflow vein in the femoral confluence in extensive chronic iliofemoral venous obstruction, using venography as the gold standard. All DCTVs performed in symptomatic patients with previous iliofemoral deep vein thrombosis subsequently submitted to venography in the period from January 2014 to August 2018 were retrospectively reviewed. Two groups were defined depending on whether thefemoral vein (FV) or thedeep femoral vein (DFV) was the dominant inflow on venography in order to identify predictors of DFV as dominant inflow in DCTV. Statistical analysis was performed with SPSS V25. A total of 30 DCTVs and subsequent venographies were reviewed. Venography identified the FV as the dominant inflow in 18 (60%) and the DFV in 12 (40%) patients. Predictors for DFV as dominant inflow were identified as follows: larger DFV diameter 50mm and 250mm below lesser trochanter (8.73 ± 4.34mm vs. 11.9 ± 3.52mm; p = 0.043 and 5.4 ± 3.90mm vs. 8.90 ± 2.70mm; p = 0.011); lower FV/DFV ratio 150mm below lesser trochanter (11.39 ± 20.01mm vs. 1.05 ± 0.47mm; p = 0.043); and presence of FV scarring/synechiae, collaterals and abnormal wall thickness (p = 0.003, p = 0.003 and p < 0.0001). In cases of extensive chronic iliofemoral venous obstruction, especially when stent deployment into the DFV is entertained, the key to success is thorough pre-procedure planning focusing on choosing the access site. This study suggests DCTV is valuable in defining the dominant iliac vein inflow, but additional findings are necessary to validate these preliminary data.