Abstract 2771: Contrast Pulse Sequence Ultrasound is a Novel Imaging Modality of Regional Perfusion in Skeletal Muscle and Myocardium after Proangiogenic Gene Therapy
Contrast-enhanced Power Doppler imaging and contrast echocardiography are used for perfusion assessment in skeletal muscle and myocardium, respectively, and can also be used to detect perfusion increases after gene therapy. However, these modalities suffer from compromised contrast agent-to-tissue specificity and spatial resolution. Contrast Pulse Sequence (CPS) is a novel ultrasound imaging modality that utilizes non-linear fundamental frequencies and higher order harmonics allowing high imaging frequencies (up to 14MHz) to construct real time perfusion images with high contrast agent-to-tissue specificity and spatial resolution. We have used CPS (CadenceTM, Acuson Sequoia 512, Siemens) with 15L8 and 3v2c transducers and SonoVue contrast agent (Bracco) to non-invasively image and quantify perfusion after angiogenic gene therapy in rabbit and mouse hindlimb ischemia and pig myocardial ischemia models. CPS was found as accurate as contrast-enhanced Power Doppler ultrasound (CEU) and contrast-enhanced MRI (Correlations with CEU: 0,974, P<0.001 and with MRI: 0,860, P<0.01) but additionally provided superior spatial resolution creating a perfusion map of the imaged area. With CPS it was possible to detect perfusion increases and defects with a high correlation to histological analysis of vasculature, almost at the capillary level. In conclusion, the CPS imaging system is a promising and cost-effective tool for non-invasive measurement of tissue ischemia and perfusion increases in small laboratory animals and could also provide a remarkable advance to the means of following patients after revascularization therapies such as angiogenic gene therapy.