The meaning of imaging characteristics in the severity of iliac vein compression syndrome

Objective To evaluate the meaning of imaging characteristics (the degree of stenosis, intraluminal spurs and collateral formation) in the severity of iliac vein compression syndrome (IVCS) and endovascular treatment. Methods Between July 2013 and December 2015, 115 patients (49 men, 66 women; 107 in left, 8 in right) with suspected IVCS were evaluated with the intent to treat iliac venous occlusion or stenosis verified by both transfemoral venography and intravascular ultrasound (IVUS). Clinical score of CEAP was 2 in 23 cases, 3 in 30 cases, 4 in 41 cases, 5 in 10 cases, 6 in 11 cases. Treatments included balloon dilation/stenting and procedures (endovenous laser ablation or stripping). Results All of the 115 limbs were successfully evaluated and treated and there was no mortality in our study. IVUS showed less than 50% stenosis in the cross-sectional area in 29 limbs (group A) , 50%-70% stenosis in 41 limbs (group B) , more than 70% stenosis in 45 limbs (group C). Balloon dilation alone was performed in 9, 16, 4 limbs in group A, B, C, respectively, while balloon dilation was combined with stent implantation in 19, 36 limbs in group B, C, respectively. Endovenous laser ablation or stripping was performed in 27, 24, 30 limbs in group A, B, C, respectively. Ninety-two cases were followed up for 2 -35 months (mean, 20.3 months). Symptoms improved in 89 cases. The mean venous clinical severity score (VCSS) was 7.5 ± 1.6 before endovascular treatment and 1.9±0.6 at one year after treatment (P<0.05). Conclusions The presence of intraluminal spurs and pelvic collateral vessels are represented as indicators of the severity and treatment of IVCS. And the degree of stenosis could not accurately be represented as the severity indicator of IVCS. Endovascular intervention is a simple and effective treatment modality that can obviously reduce lower extremity symptoms, and the intraluminal spurs dilated fully is a key point in technical aspect, while not fully expansion may be the cause of thrombosis after stenting. Key words: Iliac venous compression syndrome; Diagnosis; Intravascular ultrasound; Intraluminal spur; Stent