Tissue perfusion of patients with peripheral artery disease

Peripheral artery disease (PAD) is a common, invalidating condition, caused by insufficient oxygenation of the feet and legs due to a reduction in perfusion. This causes pain during mobilisation, chronic pain and/or wounds. Seven percent of people older than 55 years suffer from PAD in the Netherlands, in people of 85 years or older this number increases even to 56%. Chronic ischemia is present in 15% of patients and causes pain whilst resting and often wounds that do not heal well. When symptoms do not improve with physical training, it is necessary to intervene, usually with a Dotter procedure.

During this procedure it is difficult to know for sure if the operation has reached the desired effect. This is evaluated by looking at increased blood flow in the major arteries, yet relieve of the symptoms is only possible if the blood also reaches the small vessels in the skin. Therefore, ideally we would have a method that allows us to measure the skin perfusion of the lower limbs “real-time” during the operation or directly afterwards and compare it to the preoperative situation. Right now, we cannot measure the perfusion during an intervention and will only know several weeks after the procedure whether the operation has been successful.

There are several new technologies on the market such as hyperspectral imaging, laser doppler flow measurement, diffuse reflectance spectroscopy, mitochrondrial oxygen tension, and fluorescence imaging that could be of additional value in measuring the skin perfusion of patients with limb ischaemia during different moments around the operation. Our research group investigates the accuracy of these new techniques and looks at the applicability in the clinical workflow.