Thermography as a Diagnostic Tool for Early Detection of Diabetic Foot Ulceration Risk: A Review

Type 2 Diabetes Mellitus (DM2) is a disease that affects the following physiological systems: the central nervous system (CNS), the peripheral nervous system (PNS), the vascular system (VS), and the peripheral vascular system (PVS). When the PNS and PVS are affected, those complications are well known as diabetic neuropathy (DN) and diabetic vasculopathy (DV) respectively. These complications may cause lesions on the feet such as ulcers and are associated with other risk factors such as plantar pick pressure, friction from not wearing ergonomics footwear, the presence of biomechanics foot alterations, or significant temperature changes on the foot producing tissue infection that may cause lower limb amputation. The most important physiopathologies reported on the feet caused by the DN and DV are hypoesthesia and hyperthermia. These complications cause the loss of sensitivity and increase in temperature at the plantar surface respectively, and with continuously applied pressure, may initiate an ischemic or inflammatory problem. This multicausal condition of DM2 is known as Diabetic Foot Syndrome (DF), one of the main complications of the disease. Several studies have reported the correlation between ulcers and high temperatures under the plantar surface of the foot. Those temperature changes may be detected by using different methods. According to literary reviews, thermography is one of the methods most implemented by different researchers in laboratory environments. This method seems accurate in detecting temperature changes in the plantar foot anatomical regions by using image processing techniques, computer vision, and intelligent systems for improving ulcer detection in early stages of DF. The aim of this study is to define the benefits of using thermography as a future diagnostic tool for DF in a clinical environment based on the systematic literary review done in the last 15 years by BASPI-FootLab research group. Preliminary results of our review are reported in this paper.