The clinical manifestations of peripheral arterial disease (PAD), regardless of etiology, are due to a lack of blood flow to the musculature relative to its metabolism, which results in pain in the affected muscle groups. PAD affecting the lower extremities causes claudication, cramping pain in the calf, thigh or hip muscle induced by exercise. The initial test for evaluation of patients with claudication is ankle brachial index (ABI).~Therefore, a non-invasive and affordable US technique that can quantify blood perfusion and microvasculature density, without using contrast agent, will improve PAD detection in early stage and can monitor the disease progress as well as the treatment response. The investigators anticipate that our new cost-effective and non-invasive ultrasound perfusion technique offers a quantitative imaging of perfusion that would help separating PAD from non-PAD and monitor the disease progression and treatment response.
The purpose of this study is to evaluate the potential of ultrasound perfusion imaging technique for assessing the progression of peripheral arterial disease (PAD) and monitoring its response to therapy by measuring changes in microvessel alterations and perfusion variations.