Infrared 3D Thermography for Inflammation Detection in Diabetic Foot Disease: A Proof of Concept

Abstract

Background: Thermal assessment of the plantar surface of the foot using spot thermometers and thermal imaging has been proven effective in diabetic foot ulcer prevention. However, with traditional cameras this is limited to single spots or a two-dimensional (2D) view of the plantar side of foot, where only 50% of the ulcers occur. To improve ulcer detection, the view has to be extended beyond 2D. Our aim is to explore for proof of concept the combination of three-dimensional (3D) models with thermal imaging for inflammation detection in diabetic foot disease. Method: From eight participants with a current diabetic foot ulcer we simultaneously acquired a 3D foot model and three thermal infrared images using a high-resolution medical 3D imaging system aligned with three smartphone-based thermal infrared cameras. Using spatial transformations, we aimed to map thermal images onto the 3D model, to create the 3D visualizations. Expert clinicians assessed these for quality and face validity as +, +/-, -. Results: We could replace the texture maps (color definitions) of the 3D model with the thermal infrared images and created the first-ever 3D thermographs of the diabetic foot. We then converted these models to 3D PDF-files compatible with the hospital IT environment. Face validity was assessed as + in six and +/- in two cases. Conclusions: We have provided a proof of concept for the creation of clinically useful 3D thermal foot images to assess the diabetic foot skin temperature in 3D in a hospital IT environment. Future developments are expected to improve the image-processing techniques to result in easier, handheld applications and driving further research.

An Anatomical Thermal 3D Model in Preclinical Research: Combining CT and Thermal Images

“…Unlike similar approaches that have also generated thermal 3D models [ 5 , 7 , 16 , 18 ], it was possible to replace the third modality—a 3D scanner. Therefore, the anatomical thermal 3D models employed in this research were obtained from the complete set of CT image slices.…”

“…To quantify inflammation and to improve diagnostics and monitoring, a thermal 3D scan model for human medicine was introduced by Chromy and Klima [ 5 ], calculating a 3D view of the acquired 2D thermal images and a 3D scan of an injured toe. Similar approaches were followed by Grubišiü and Boš [ 7 ] and van Doremalen [ 16 ] for diabetic foot disease, presenting the development of a system combining an active scanning system and a thermal camera. These approaches calculate a 3D model of the thermal images.…”

Multimodal and Multiview Wound Monitoring with Mobile Devices

“…Moreover, further research is needed on the use of thermal metrics obtained from low-cost portable devices, which have less thermal accuracy and reduced thermal image resolution than expensive high-end cameras. Previous studies propose the use of different metrics, and most of them use high-end thermal cameras that have higher thermal accuracy than low-cost commercial devices [11,13,14]. Thus, we are looking forward to conducting a longitudinal study to analyze the metrics in the literature, and identify those that have predictive power in wound evolution and can be used as follow-up metrics in the specific case of using low-cost hand-held devices.…”

“…The 3D model and the thermal surface distribution can provide geometrical (areas and volume) and thermal metrics in addition to a visualization that helps raise patient awareness of their wound status. Most studies show the feasibility of creating 3D surface thermography using expensive devices and cameras in static positions [13,14]; however, thermography from a static viewing position limits the observation and analysis of wounds to a single view and underexploits the 3D component.…”

Thermographic Control of Pediatric Dental Patients During the SARS-CoV-2 Pandemics Using Smartphones

“…For some time now, there have been IR-TICs on the market recognized for their excellent characteristics in terms of accuracy and sensitivity and at affordable prices that connecting to common smartphones can provide excellent thermographic images also useful for diagnostic purposes [33][34][35]. This study aimed to evaluate the use of IR-TIC on a smartphone as a reliable device for body temperature measurement in children.…”