Infrared Thermography Compared to Standard Care in the Prevention and Care of Diabetic Foot: A Cost Analysis Utilizing Real-World Data and an Expert Panel

Beyond visual inspection: The value of infrared thermography in skin diseases, a scoping review

Although warmth is a key sign of inflammatory skin lesions, an objective assessment and follow-up of the temperature changes are rarely done in dermatology. The recent availability of accurate, sensitive and cost-effective thermography devices has made the implementation of thermography in clinical settings feasible. The aim of this scoping review is to summarize the evidence around the value and pitfalls of infrared thermography (IRT) when used in the dermatology clinic. A systematic literature search was done for original articles using IRT in skin disorders. The results concerning the potential of IRT for diagnosis, severity staging and monitoring of skin diseases were collected. The data on the sensitivity and specificity of IRT were extracted. Numerous studies have investigated IRT in various skin diseases, revealing its significant value in wound management, skin infections (e.g. cellulitis), vascular abnormalities and deep skin inflammation (e.g. hidradenitis suppurativa). For other dermatological applications such as the interpretation of intradermal and patch allergy testing, hyper-/anhidrosis, erythromelalgia, cold urticaria and lymph node metastases more complex calculations, provocation tests or active cooling procedures are required. Dermatologists should be aware of a learning curve of IRT and recognize factors contributing to false positive and false negative results. Nonetheless, enough evidence is available to recommend IRT as a supplement to the clinical evaluation for the diagnosis, severity and follow-up of several skin diseases.

Cost-effectiveness of temperature monitoring to help prevent foot ulcer recurrence in people with diabetes: A multicenter randomized controlled trial

AIMS

Diabetes-related foot ulcers are common, costly, and frequently recur. Multiple interventions help prevent these ulcers. However, none of these have been prospectively investigated for cost-effectiveness. Our aim was to evaluate the cost-effectiveness of at-home skin temperature monitoring to help prevent diabetes-related foot ulcer recurrence.

MATERIALS AND METHODS

Multicenter randomized controlled trial. We randomized 304 persons at high diabetes-related foot ulcer risk to either usual foot care plus daily at-home foot skin temperature monitoring (intervention) or usual care alone (control). Primary outcome was cost-effectiveness based on foot care costs and quality-adjusted life years (QALY) during 18 months follow-up. Foot care costs included costs for ulcer prevention (e.g., footwear, podiatry) and for ulcer treatment when required (e.g., consultation, hospitalisation, amputation). Incremental cost-effectiveness ratios were calculated for intervention versus usual care using probabilistic sensitivity analysis for willingness-to-pay/accept levels up to €100,000.

RESULTS

The intervention had a 45% probability of being cost-effective at a willingness-to-accept of €50,000 per QALY lost. This resulted from (non-significantly) lower foot care costs in the intervention group (€6067 vs. €7376; p = 0.45) because of (significantly) fewer participants with ulcer recurrence(s) in 18 months (36% vs. 47%; p = 0.045); however, QALYs were (non-significantly) lower in the intervention group (1.09 vs. 1.12; p = 0.35), especially in those without foot ulcer recurrence (1.09 vs. 1.17; p = 0.10).

CONCLUSIONS

At-home skin temperature monitoring for diabetes-related foot ulcer prevention compared with usual care is at best equally cost-effective. The intervention resulted in cost-savings due to preventing foot ulcer recurrence and related costs, but this came at the expense of QALY loss, potentially from self-monitoring burdens.

Improving Physical, Physiological, and Psychological Health Outcomes in Patients with Diabetic Foot Ulcers - State of the Art

Diabetic foot disease is a complex and challenging complication of diabetes mellitus, which imposes a significant burden of disease on patients, their carers, and the wider health systems. Recurrence rates are high, and current evidence indicates a high mortality associated with it. While management algorithms have primarily focused on the physical aspects of healing, there is increasing recognition of the critical role played by psychological and biomechanical factors in the development and resolution of diabetic foot disease. Therefore, in this paper, we aim to explore how diabetic foot outcomes can be improved by addressing not only the physical but also the psychological and biomechanical aspects that are integral to the development of this condition and its optimal resolution. We explore new technologies that allow for non-invasive objective assessment of the diabetic foot at risk, and we also explore the role of understanding biomechanics, which is essential to determining risk of foot disease, but also the potential for recurrence. In addition, we discuss the evidence linking depression and cognitive impairment to diabetic foot disease and offer our insight on the research direction required before implementing novel information into front-line clinics.

Diabetic Plantar Foot Segmentation in Active Thermography Using a Two-Stage Adaptive Gamma Transform and a Deep Neural Network

Pathological conditions in diabetic feet cause surface temperature variations, which can be captured quantitatively using infrared thermography. Thermal images captured during recovery of diabetic feet after active cooling may reveal richer information than those from passive thermography, but diseased foot regions may exhibit very small temperature differences compared with the surrounding area, complicating plantar foot segmentation in such cold-stressed active thermography. In this study, we investigate new plantar foot segmentation methods for thermal images obtained via cold-stressed active thermography without the complementary information from color or depth channels. To better deal with the temporal variations in thermal image contrast when planar feet are recovering from cold immersion, we propose an image pre-processing method using a two-stage adaptive gamma transform to alleviate the impact of such contrast variations. To improve upon existing deep neural networks for segmenting planar feet from cold-stressed infrared thermograms, a new deep neural network, the Plantar Foot Segmentation Network (PFSNet), is proposed to better extract foot contours. It combines the fundamental U-shaped network structure, a multi-scale feature extraction module, and a convolutional block attention module with a feature fusion network. The PFSNet, in combination with the two-stage adaptive gamma transform, outperforms multiple existing deep neural networks in plantar foot segmentation for single-channel infrared images from cold-stressed infrared thermography, achieving an accuracy of 97.3% and 95.4% as measured by Intersection over Union (IOU) and Dice Similarity Coefficient (DSC) respectively.

The effectiveness of a thermography-driven preventive foot care protocol on the recurrence of diabetic foot ulcers in low-medical resource settings: An open-labeled randomized controlled trial

BACKGROUND

Plantar temperature monitoring, along with a comprehensive preventive foot care approach, is utilized to prevent recurrence of diabetic foot ulcers. However, there is a lack of standardized protocols for individuals with diabetic foot ulcer history in low-medical resource countries.

OBJECTIVE

This study investigated the efficacy of nurse-led, thermographic-evaluation-guided foot care in preventing diabetic foot ulcer recurrence in a low-medical resource country.

DESIGN

Single-blind, 1:1 allocation randomized controlled trial.

SETTINGS

Two wound care facilities with wound care nurse specialists in Indonesia.

PARTICIPANTS

120 patients with a diabetic foot ulcer history.

INTERVENTION

In the intervention group, baseline risk assessment including smartphone thermography evaluation was performed. Personalized foot care and education were conducted monthly for participants whose thermographs showed increased foot lesion temperature at baseline risk assessment. The control group received usual care and education using a booklet at baseline. The follow-up period was six months.

MAIN OUTCOME

Time to recurrence was evaluated using Kaplan-Meier survival analysis, and between-group comparisons were performed using the log-rank test. Potential risk factors were incorporated into the multivariate Cox regression model. Secondary outcomes included quality of life (European Quality of Life 5 Dimensions 3 Level Version) and foot care behavior, were analyzed using Mixed Models for Repeated Measures at baseline, third, and sixth follow-up (3 and 6 months from baseline).

RESULTS

120 participants (intervention 60, control 60) were randomized. The intervention group had a significantly lower recurrence rate than the control group (15% vs. 35%, p = 0.011) and a significant difference in time to ulceration (log-rank test, p = 0.009) after a 6-month follow-up period. Intervention care reduced the risk of diabetic foot ulcer recurrence by 59% (Hazard ratio 0.41, 95% confidence interval 0.18, 0.96, p = 0.039) in multivariate Cox regression analysis. On the third follow-up, total diabetic foot care behavior score (p < 0.001) was significantly improved by the intervention. On the sixth follow-up, mobility (p = 0.020), self-care (p = 0.023), pain/discomfort (p < 0.001), anxiety/depression (p = 0.016), EuroQol Visual Analogue Scale score (p = 0.002), and total diabetic foot care behavior score (p < 0.001) showed significant improvements in the intervention group.

CONCLUSIONS

Foot care and personalized education delivered at a frequency based on the risk level assessed by thermography effectively reduced diabetic foot ulcer recurrence, and improved quality of life and foot care behaviors.

REGISTRATION NUMBER

UMIN000039012.

TWEETABLE ABSTRACT

Nurse-led diabetic foot care and education reduced diabetic foot ulcer recurrence in Indonesia.