Abstract: Background and aim: in Russian Federation, more than 10 million people suffer from peripheral artery disease (PAD), and from chronic limb-threatening ischemia (CLTI) as one of it’s complications. According to Russian guidelines on treatment of patients with CLTI, the initial diagnosis should include measurement of ankle-brachial and finger-brachial indices (ABI, ТВ I), as well as ultrasound duplex scanning (USDS) - however, the sensitivity and diagnostic accuracy of these methods are often insufficient. In this review, we have summarized the entire range of modern instrumental methods for early and effective diagnosis of critical lower limb-threatening ischemia and for the evaluation of limb perfusion. Materials and methods: 31 sources of domestic and foreign literature published in last 5 years on the issue of modern possibilities for early precision diagnosis of critical limb-threatening ischemia were examined. Results and conclusions: AHA Experts recommend some experimental technologies for evaluating lower limb perfusion, including angiography with indigocarmine, perfusion computed tomography (CT perfusion), magnetic resonance imaging (MRI), contrast echography, and hyperspectral imaging. Among other things, implantable bio-sensors can be identified: for example, oxygen-platform LuMee, which works in real time and provides continuous monitoring of oxygen levels in tissues. New technologies allow us to improve the accuracy of diagnosis and quality of treatment of patients with CLTI. It is worth considering switching from traditional methods to more modern ones, which can significantly reduce the frequency of amputations and the risk of disability and improve the quality of life of our patients. References 1. Lobachev АА. 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