Chapter 7 - The diagnosis of major venous outflow obstruction in chronic venous insufficiency

Abstract

Given the continuity of the venous system that characterizes the relationship between abdominal, pelvic, and infrainguinal venous anatomic segments and related venous hemodynamics, it is imperative that a comprehensive approach to evaluate the venous system as a continuum rather than isolated venous segments is undertaken in patients with clinically suspected venous outflow obstruction. Although valvular dysfunction and resultant venous reflux are major causes of venous hypertension that underlies the clinical manifestations of chronic venous insufficiency, an increasing amount of studies suggest that iliac venous outflow obstruction plays a more important role in the pathogenesis of venous insufficiency than previously estimated. The combination of reflux and obstruction produces the highest levels of venous hypertension and the most severe clinical symptoms. Therefore, timely and accurate diagnosis of venous obstruction (including May–Thurner syndrome and pelvic venous congestion) is critical in the management of these patients. This chapter will examine diagnostic algorithms and diagnostic modalities used for the assessment of venous leg ulcers in the settings of underlying venous outflow obstruction.