Low-Intensity Pulsed Ultrasound

Abstract

Cell and gene therapies are invasive and may have complexity of handling and some safety concerns for patients with critical limb ischemia. Low-intensity pulsed ultrasound (LIPUS) irradiation has been widely used to promote the healing of bone fractures in humans. It is postulated that the initial step of bone fracture healing by LIPUS is angiogenesis, and subsequent neovascularization leads to osteoblasts being conveyed to the bone fracture site. Indeed, a few studies have shown that LIPUS induces angiogenesis in experimental hind-limb ischemic models. Unfortunately, there is no information on the effects of LIPUS on angiogenesis in humans. However, LIPUS irradiation should have beneficial effects on ischemia of extremities by inducing angiogenesis in patients with peripheral arterial disease (PAD). The use of LIPUS would be a noninvasive, safe, and effective method for improving clinical symptoms in patients with PAD. It is expected that the use of LIPUS would be a novel strategy for therapeutic angiogenesis in PAD patients with a wide range of limb ischemia severities. In this chapter, we focus on the effect of LIPUS on angiogenesis, the mechanism of LIPUS-induced angiogenesis, and the possibility of improvement of clinical symptoms by LIPUS irradiation in patients with PAD.