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The beneficial role of intravascular ultrasound in the diagnosis and treatment of nonthrombotic iliac venous obstructions as compared with traditional venography in the Chinese population

PURPOSE: The efficacy of intravascular ultrasound (IVUS) in diagnosing obstructive venous lesions has been established in the Western countries; however, its beneficial role in the Asian population is seldom reported. Because IVUS is still not widely used in China, we, therefore, investigated whether the salutary effect of IVUS on the diagnosis and treatment of iliac venous outflow obstructions could also be extended to the Chinese population. MATERIALS AND METHODS: This was a prospective single-center study. Patients with nonthrombotic iliac venous obstructions were consecutively enrolled from September 2017 to September 2019. IVUS and venography were performed for every participant. The anatomic characteristics of the venous lesions were measured by these two imaging modalities and then compared with each other. Venous lesions were divided into the collateral and noncollateral group according to the presence of collaterals on venographic images, and comparison was performed between the two groups. The difference of lesion diameter or area at the most compression site was also observed after the endovascular intervention. RESULTS: A total of 50 patients with 59 limbs were eligible (males, 25; females, 25; mean age 63.46 ± 8.07). The clinical-etiology-anatomy-pathophysiology classification was C4: 43 (72.88%), C5: 6 (10.17%), and C6: 10 (16.95%). Compared with IVUS, the diameter and area stenosis calculated by traditional venography were dramatically lower than that measured by IVUS (diameter stenosis, 38.56% ± 17.76% vs. 64.55% ± 15.96%, P CONCLUSIONS: Compared with IVUS, traditional venography underestimates the degree of stenosis and misses significant iliac venous obstructive lesions. The collaterals presented by venography is not a reliable indicator in distinguishing significant lesions. IVUS is a valuable and effective imaging modality in the diagnosis and treatment of nonthrombotic iliac venous obstructions in the Chinese population.