Analysis of patent, unstented lower extremity vein segment diameters in 266 patients with venous disease.

Objective: The objective of this study was to characterize the average maximum diameters of widely patent lower extremity vein segments in patients with underlying venous disease and the demographic factors that affect these diameters.

Methods: Maximum axial diameters of each deep vein segment from the diaphragm to the knee were measured from computed tomography venography studies for all patients who underwent venous stent placement during a 20-year period at a single quaternary venous referral institution. Limbs containing only widely patent, unstented vein segments without variant anatomy were identified for inclusion. The final analysis involved diameter measurements from 870 imaging studies of 266 patients. Multivariate linear regression was used to identify factors associated with vein segment diameters.

Results: Average vein segment diameters ranged from 7.8 mm for the left and right femoral veins to 27.9 mm for the long axis of the suprarenal inferior vena cava. Multivariate linear regression demonstrated that women had larger IVC, common iliac vein, and external iliac vein diameters, whereas men had larger common femoral veins. Laterality, height, weight, and sex also had statistically significant associations with the diameters of select vein segments.

Conclusions: This study provides an estimate of the average diameters of widely patent deep vein segments in the lower extremities from the diaphragm to the knees in patients with underlying venous disease and characterizes covariates that significantly affect vein diameter. These findings may help interventionalists better select devices for endovascular intervention.