Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK.
St George's Vascular Institute, St James Wing, St George's Hospital, London, UK.
Diabetes Metab Res Rev. 2016 Jan;32 Suppl 1:232-8. doi: 10.1002/dmrr.2756.
Assessment of foot perfusion is a vital step in the management of patients with diabetic foot ulceration, in order to understand the risk of amputation and likelihood of wound healing. Underlying peripheral artery disease is a common finding in patients with foot ulceration and is associated with poor outcomes. Assessment of foot perfusion should therefore focus on identifying the presence of peripheral artery disease and to subsequently estimate the effect this may have on wound healing. Assessment of perfusion can be difficult because of the often complex, diffuse and distal nature of peripheral artery disease in patients with diabetes, as well as poor collateralisation and heavy vascular calcification. Conventional methods of assessing tissue perfusion in the peripheral circulation may be unreliable in patients with diabetes, and it may therefore be difficult to determine the extent to which poor perfusion contributes to foot ulceration. Anatomical data obtained on cross-sectional imaging is important but must be combined with measurements of tissue perfusion (such as transcutaneous oxygen tension) in order to understand the global and regional perfusion deficit present in a patient with diabetic foot ulceration. Ankle-brachial pressure index is routinely used to screen for peripheral artery disease, but its use in patients with diabetes is limited in the presence of neuropathy and medial arterial calcification. Toe pressure index may be more useful because of the relative sparing of pedal arteries from medial calcification but may not always be possible in patients with ulceration. Fluorescence angiography is a non-invasive technique that can provide rapid quantitative information about regional tissue perfusion; capillaroscopy, iontophoresis and hyperspectral imaging may also be useful in assessing physiological perfusion but are not widely available. There may be a future role for specialized perfusion imaging of these patients, including magnetic resonance imaging techniques, single-photon emission computed tomography and PET-based molecular imaging; however, these novel techniques require further validation and are unlikely to become standard practice in the near future.
足部灌注评估是糖尿病足溃疡患者管理的重要步骤，目的是了解截肢风险和伤口愈合的可能性。糖尿病患者常存在下肢动脉病变等潜在周围血管疾病，且预后较差。因此，足部灌注评估应重点识别周围血管疾病的存在，并随后估计其对伤口愈合的影响。由于糖尿病患者的外周动脉疾病通常较为复杂、弥漫且位于远端，侧支循环较差且血管钙化严重，因此灌注评估可能较为困难。评估外周循环组织灌注的传统方法在糖尿病患者中可能不可靠，因此可能难以确定灌注不良对足部溃疡的影响程度。在横断面成像中获得的解剖学数据很重要，但必须与组织灌注（如经皮氧分压）测量相结合，以便了解糖尿病足溃疡患者的整体和局部灌注不足情况。踝肱指数通常用于筛查周围血管疾病，但在存在神经病变和动脉钙化的情况下，其在糖尿病患者中的应用受限。趾压指数可能更有用，因为足背动脉较少受到动脉钙化的影响，但在溃疡患者中可能并不总是可行。荧光血管造影是一种非侵入性技术，可快速提供关于局部组织灌注的定量信息；毛细血管镜检查、离子电渗疗法和高光谱成像也可用于评估生理灌注，但尚未广泛应用。这些患者的专门灌注成像可能具有未来的应用前景，包括磁共振成像技术、单光子发射计算机断层扫描和基于 PET 的分子成像；然而，这些新技术需要进一步验证，且在不久的将来不太可能成为标准实践。
