Dynamic fluorescence imaging of indocyanine green for reliable and sensitive diagnosis of peripheral vascular insufficiency

Quantitative measurement of functional tissue perfusion is essential for early diagnosis and proper treatment of peripheral arterial occlusive disease (PAOD). We have previously demonstrated that dynamic imaging of near-infrared fluorophore indocyanine green (ICG) can be a noninvasive and sensitive tool to measure tissue perfusion. In the present study, we investigated the clinical efficacy of ICG perfusion imaging method for the diagnosis of PAOD. Total nineteen PAOD patients and age-matched controls (n = 10) were evaluated for lower extremity tissue perfusion using ICG perfusion imaging. The perfusion rates of the lower extremities with severe PAOD (n = 25 legs, 16.6 ± 8.3%/min) were significantly lower than those of normal controls (38.1 ± 17.3%/min, p < 0.001). In cases of mild PAOD, the perfusion rates (n = 11 legs, 18.3 ± 10.3%/min) were also significantly lower compared to the control; while the conventional ankle-brachial index (ABI) test failed to detect mild functional impairment. These results collectively indicate that ICG perfusion imaging can be a very effective tool for diagnosis of PAOD with a superior efficacy in comparison to conventional ABI test.