R F M van Doremalen1, J J van Netten2, J G van Baal3, M M R Vollenbroek-Hutten4, F van der Heijden5. 1. University of Twente, Drienerlolaan 5, 7522 NB Enschede, the Netherlands; Ziekenhuisgroep Twente, Zilvermeeuw 1, 7609 PP Almelo, the Netherlands. Electronic address: r.f.m.vandoremalen@utwente.nl. 2. Ziekenhuisgroep Twente, Zilvermeeuw 1, 7609 PP Almelo, the Netherlands; School of Clinical Sciences, Queensland University of Technology, 2 George St, Brisbane City, QLD 4000, Australia. 3. Ziekenhuisgroep Twente, Zilvermeeuw 1, 7609 PP Almelo, the Netherlands; Cardiff University, Cardiff, Wales, United Kingdom. 4. University of Twente, Drienerlolaan 5, 7522 NB Enschede, the Netherlands; Ziekenhuisgroep Twente, Zilvermeeuw 1, 7609 PP Almelo, the Netherlands. 5. University of Twente, Drienerlolaan 5, 7522 NB Enschede, the Netherlands.
Abstract
AIMS: Infrared thermal imaging (IR) is not yet routinely implemented for early detection of diabetic foot ulcers (DFU), despite proven clinical effectiveness. Low-cost, smartphone-based IR-cameras are now available and may lower the threshold for implementation, but the quality of these cameras is unknown. We aim to validate a smartphone-based IR-camera against a high-end IR-camera for diabetic foot assessment. METHODS: We acquired plantar IR images of feet of 32 participants with a current or recently healed DFU with the smartphone-based FLIR-One and the high-end FLIR-SC305. Contralateral temperature differences of the entire plantar foot and nine pre-specified regions were compared for validation. Intra-class correlations coefficient (ICC(3,1)) and Bland-Altman plots were used to test agreement. Clinical validity was assessed by calculating statistical measures of diagnostic performance. RESULTS: Almost perfect agreement was found for temperature measurements in both the entire plantar foot and the combined pre-specified regions, respectively, with ICC values of 0.987 and 0.981, Bland-Altman plots' mean Δ = -0.14 and Δ = -0.06. Diagnostic accuracy showed 94% and 93% sensitivity, and 86% and 91% specificity. CONCLUSIONS: The smartphone-based IR-camera shows excellent validity for diabetic foot assessment.
AIMS: Infrared thermal imaging (IR) is not yet routinely implemented for early detection of diabetic foot ulcers (DFU), despite proven clinical effectiveness. Low-cost, smartphone-based IR-cameras are now available and may lower the threshold for implementation, but the quality of these cameras is unknown. We aim to validate a smartphone-based IR-camera against a high-end IR-camera for diabetic foot assessment. METHODS: We acquired plantar IR images of feet of 32 participants with a current or recently healed DFU with the smartphone-based FLIR-One and the high-end FLIR-SC305. Contralateral temperature differences of the entire plantar foot and nine pre-specified regions were compared for validation. Intra-class correlations coefficient (ICC(3,1)) and Bland-Altman plots were used to test agreement. Clinical validity was assessed by calculating statistical measures of diagnostic performance. RESULTS: Almost perfect agreement was found for temperature measurements in both the entire plantar foot and the combined pre-specified regions, respectively, with ICC values of 0.987 and 0.981, Bland-Altman plots' mean Δ = -0.14 and Δ = -0.06. Diagnostic accuracy showed 94% and 93% sensitivity, and 86% and 91% specificity. CONCLUSIONS: The smartphone-based IR-camera shows excellent validity for diabetic foot assessment.
Authors: Rob F M van Doremalen; Jaap J van Netten; Jeff G van Baal; Miriam M R Vollenbroek-Hutten; Ferdinand van der Heijden Journal: J Diabetes Sci Technol Date: 2019-06-14
Authors: Jonathan Golledge; Malindu Fernando; Peter Lazzarini; Bijan Najafi; David G Armstrong Journal: Sensors (Basel) Date: 2020-08-13 Impact factor: 3.576