Quantitative and functional analysis of regional perfusion in peripheral tissue and application for peripheral vascular diseases

Abstract

Accurate measurement of peripheral tissue perfusion is necessary but challenging in diagnosing peripheral vascular insufficiency. Significant attention has also been given to in vivo near-infrared (NIR) fluorescence imaging because of deep tissue penetration due to low absorbance and scattering. In this study, a new method, ICG (indocyanine green) perfusion imaging, was developed for measuring peripheral tissue perfusion. A NIR fluorescence imaging was approached for evaluation of peripheral tissue perfusion that employs the intravenous injection of ICG dye, planar imaging with a CCD digital imaging system, and analysis of spatiotemporal dynamics. The method was evaluated using a murine model of hindlimb ischemia, and therapeutic interventions directed at stimulation of angiogenesis. Moreover, the method was applied to measure perfusion rate of human lower extremities. In this clinical application, this method presents high specificity and sensitivity to diagnose patients with peripheral vascular insufficiencies in lower extremities, compared with the standard methods, CT-angiography and ankle brachial index. These studies collectively suggest that ICG perfusion imaging is feasible method not only for therapeutic angiogenesis studies in animal experimentation but also for diagnosing and monitoring treatment effects of peripheral vascular diseases in clinical setting.