In the United States, 3 to 4 percent of the population suffer from CVI (Coon et al., 1973). Approximately 1.5 percent of adults will be affected by venous ulceration. In 2007, more than 500,000 individuals in the United States had venous stasis ulcers.
Risk factors for CVI include older age, family history, multiple pregnancies, standing occupation, obesity in females, history of leg trauma, and prior deep venous thrombosis (Adhikari et al., 2000; Criqui et al., 2007). The annual incidence of varicose veins in the Framingham study was 2.6 percent in women and 1.9 percent in men. The prevalence of changes in skin pigmentation varied between 3 and 13 percent in the population. The presence of active or healed ulcers varied between 1.0 and 2.7 percent.
CVI is often diagnosed by a visual inspection of the lower limbs to identify the presence of characteristic trophic changes of the skin, such as hyperpigmentation, edema, and ulcers (Criqui et al., 2003). Duplex ultrasound has become the standard for diagnosing the underlying venous reflux or obstruction, and is a procedure that is noninvasive and highly accurate (Neglen and Raju, 1992). The duplex ultrasound examination can detect reflux, or reverse flow of venous blood through a valve, and the probe can detect incompressibility of a vein, indicating obstruction from a prior blood clot. Other diagnostic techniques include contrast venography and plethysmography (Meissner et al., 2007).
Visible changes in the lower extremity consistent with CVI should not be assumed to be caused by CVI without documentation of venous reflux or obstruction (Criqui et al., 2003). Other conditions, such as right heart failure, can produce leg edema. In addition, distal leg swelling can reflect impaired lymphatic rather than venous drainage, a condition known as lymphedema. Lymphedema can be congenital, postinfectious, or posttraumatic, or can result from cancer or other surgery (Rockson, 2010). It is associated with functional limitations and reduced quality of life comparable to that reported by patients with venous leg ulcers (Augustin et al., 2005). There is no listing for lymphedema but the current introductory section of the cardiovascular system stipulates that it can medically equal the CVI listing in severity. Nevertheless, the committee believes that an accurate diagnosis should be made before granting disability for lymphedema.
Seven clinical categories have been developed to help clinicians understand and categorize the nature of chronic peripheral venous disease (see Table 9-1). The etiology of these disorders may be described as congenital, primary (i.e., not associated with an identifiable mechanism of venous dys-