Use of smartphone attached mobile thermography assessing subclinical inflammation: a pilot study

Clinical Applications, Legal Considerations and Implementation Challenges of Smartphone-Based Thermography: A Scoping Review

Medical thermography is a non-invasive technique that allows the measurement of the temperature of the human body surface, exploiting the heat emitted by the body through the skin in the form of infrared electromagnetic radiation. Recently, smartphone-based thermography (ST) has drawn considerable attention. This scoping review (SR) aims to describe its current applications and reliability based on currently available research findings, also taking into account the medico-legal implications linked to its use. A search of the sources was conducted on multiple databases (PubMed, Scopus, Cochrane, Lilacs, Google Scholar). Based on a set of eligibility criteria, all articles deemed useful were included in the SR. Collected data, processed with descriptive statistics, are then discussed. From the initial 241 results, after duplicate removal and full-text reading based on inclusion/exclusion criteria, 20 articles were classified according to the main characteristics and indications and outcomes are highlighted based on clinical evidence. The most frequently documented fields of ST are wound care management and vascular surgery. Other disciplines are less explored (dentistry, ophthalmology, otorhinolaryngology, orthopedics, etc.). Practicality, operational simplicity and affordability of mobile thermographic devices are the chief strengths of this technology. Comparative studies with traditional thermal imaging methods are poor in terms of the number of patients analyzed but this technology showed high sensitivity and accuracy in the large number of patients enrolled in observational studies, encouraging the development of further operational protocols in all medical specialties. Gaining a deeper understanding of such techniques will also help settle the medico-legal issues which may arise from the clinical implementation of ST, thus appraising its reliability and safety from that perspective as well.

The role of thermography in assessment of wounds. A scoping review

Assessment of wounds based on visual appearance has poor inter- and intra-rater reliability and it is difficult to differentiate between inflammation and infection. Thermography is a user-friendly quantitative image technique that collects the skin surface temperature pattern of the wound area and immediately visualizes the temperatures as a rainbow coloured diagram. The aim of this scoping review is to map and summarize the existing evidence on how thermography has been used to assess signs of inflammation in humans and animals with surgical or traumatic wounds. The method follows the Joanna Briggs Institute methodology. The databases searched were PubMed, Embase, CINAHL and Cochrane Library. 3798 sources were identified, 2666 were screened on title and abstract, 99 on full text and 19 studies were included for review. We found that the literature is diverse and originates from a variety of scientific fields. Thermography has been used to detect and predict inflammation and infection in surgical wounds. Grading systems based on the visual appearance correlate to temperature patterns detected with thermography. The general tendency is that thermography detects the temperature in a wound with inflammation to be warmer than a reference area or the same skin area before surgery. In a surgical wound the temperature is elevated 1-2 weeks after surgery due to natural physiological inflammation that induces healing, after 2 weeks the temperature of the wound area slowly and steady decreases to baseline over 1-3 months. If a secondary temperature peak happens during the healing phase of a surgical wound, it is likely that infection has occurred. Modern handheld thermographic cameras might be a promising tool for the clinician to quickly quantify the temperature pattern of surgical wounds to distinguish between inflammation and infection. However, firm evidence supporting infection thermography surveillance of surgical wounds as a technique is missing.

Application of smartphone-based infrared thermography devices for ocular surface thermal imaging

Infrared thermography (IRT) is a well-known imaging technique that provides a non-invasive displaying of the ocular surface temperature distribution. Currently, compact smartphone-based IRT devices, as well as special software for processing thermal images, have become available. The study aimed to determine the possible use of smartphone-based IRT devices for real-time ocular surface thermal imaging. This study involved 32 healthy individuals (64 eyes); 10 patients (10 eyes) with proliferative diabetic retinopathy (PDR) and absolute glaucoma; 10 patients (10 eyes) with PDR, who underwent vitreoretinal surgery. In all cases, simultaneous ocular surface IRT of both eyes was performed. In healthy individuals, the ocular surface temperature (OST) averaged 34.6 ± 0.8 °C and did not differ substantially between the paired eyes, in different age groups, and after pupil dilation. In our study, high intraocular pressure was accompanied by a decrease in OST in all cases. After vitreoretinal surgery in cases with confirmed subclinical inflammation, the OST was higher than the baseline and differed from that of the paired eye by more than 1.0 °C. These results highlight that smartphone-based IRT imaging could be useful for the non-invasive detection of OST asymmetry between paired eyes due to increased intraocular pressure or subclinical inflammation.

A Scoping Review of Wearable Technologies for Use in Individuals With Intellectual Disabilities and Diabetic Peripheral Neuropathy

BACKGROUND

Individuals with intellectual disabilities (IDs) are at risk of diabetes mellitus (DM) and diabetic peripheral neuropathy (DPN), which can lead to foot ulcers and lower-extremity amputations. However, cognitive differences and communication barriers may impede some methods for screening and prevention of DPN. Wearable and mobile technologies-such as smartphone apps and pressure-sensitive insoles-could help to offset these barriers, yet little is known about the effectiveness of these technologies among individuals with ID.

METHODS

We conducted a scoping review of the databases Embase, PubMed, and Web of Science using search terms for DM, DPN, ID, and technology to diagnose or monitor DPN. Finding a lack of research in this area, we broadened our search terms to include any literature on technology to diagnose or monitor DPN and then applied these findings within the context of ID.

RESULTS

We identified 88 articles; 43 of 88 (48.9%) articles were concerned with gait mechanics or foot pressures. No articles explicitly included individuals with ID as the target population, although three articles involved individuals with other cognitive impairments (two among patients with a history of stroke, one among patients with hemodialysis-related cognitive changes).

CONCLUSIONS

Individuals with ID are not represented in studies using technology to diagnose or monitor DPN. This is a concern given the risk of DM complications among patients with ID and the potential for added benefit of such technologies to reduce barriers to screening and prevention. More studies should investigate how wearable devices can be used among patients with ID.

Machine Learning Approaches for the Image-Based Identification of Surgical Wound Infections: Scoping Review

BACKGROUND

Surgical site infections (SSIs) occur frequently and impact patients and health care systems. Remote surveillance of surgical wounds is currently limited by the need for manual assessment by clinicians. Machine learning (ML)-based methods have recently been used to address various aspects of the postoperative wound healing process and may be used to improve the scalability and cost-effectiveness of remote surgical wound assessment.

OBJECTIVE

The objective of this review was to provide an overview of the ML methods that have been used to identify surgical wound infections from images.

METHODS

We conducted a scoping review of ML approaches for visual detection of SSIs following the JBI (Joanna Briggs Institute) methodology. Reports of participants in any postoperative context focusing on identification of surgical wound infections were included. Studies that did not address SSI identification, surgical wounds, or did not use image or video data were excluded. We searched MEDLINE, Embase, CINAHL, CENTRAL, Web of Science Core Collection, IEEE Xplore, Compendex, and arXiv for relevant studies in November 2022. The records retrieved were double screened for eligibility. A data extraction tool was used to chart the relevant data, which was described narratively and presented using tables. Employment of TRIPOD (Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis) guidelines was evaluated and PROBAST (Prediction Model Risk of Bias Assessment Tool) was used to assess risk of bias (RoB).

RESULTS

In total, 10 of the 715 unique records screened met the eligibility criteria. In these studies, the clinical contexts and surgical procedures were diverse. All papers developed diagnostic models, though none performed external validation. Both traditional ML and deep learning methods were used to identify SSIs from mostly color images, and the volume of images used ranged from under 50 to thousands. Further, 10 TRIPOD items were reported in at least 4 studies, though 15 items were reported in fewer than 4 studies. PROBAST assessment led to 9 studies being identified as having an overall high RoB, with 1 study having overall unclear RoB.

CONCLUSIONS

Research on the image-based identification of surgical wound infections using ML remains novel, and there is a need for standardized reporting. Limitations related to variability in image capture, model building, and data sources should be addressed in the future.

Update on the Use of Infrared Thermography in the Early Detection of Diabetic Foot Complications: A Bibliographic Review

Foot lesions are among the most frequent causes of morbidity and disability in the diabetic population. Thus, the exploration of preventive control measures is vital for detecting early signs and symptoms of this disease. Infrared thermography is one of the complementary diagnostic tools available that has proven to be effective in the control of diabetic foot. The last review on this topic was published in 2015 and so, we conducted a bibliographic review of the main databases (PubMed, the Web of Science, Cochrane library, and Scopus) during the third quarter of 2023. We aimed to identify the effectiveness of infrared thermography as a diagnostic element in pre-ulcerous states in diabetic patients and to detect diabetic foot ulcer complications. We obtained a total of 1199 articles, 26 of which were finally included in the present review and published after 2013. After analyzing the use of infrared thermography in diabetic patients both with and without ulcers, as well as in healthy individuals, we concluded that is an effective tool for detecting early-stage ulcers in diabetic foot patients.

INDIFURUTO: A novel tool for assessing diabetic foot recurrence risk in type 2 diabetes

This study aimed to evaluate diabetic foot ulcer recurrence using the Indonesia Diabetic Foot Ulcer Recurrence Assessment Tool (INDIFURUTO), a new diabetic foot risk recurrence assessment tool. This study used a prospective cohort design. A total of thirty-three participants met the inclusion criteria. We used sensitivity, specificity values, AUC, and, respectively, a 95% confidence interval (CI) to calculate prognostic accuracy measures. The results showed that this study had an AUC of 0,97 [95% confidence interval (CI) 0.91-1.00]. The cut-off point (Youden Index) was <45, with sensitivity and specificity values of 100% and 90%, respectively. The utilization of this model can facilitate the monitoring and enhancement of foot ulcer recurrence prevention in individuals diagnosed with diabetes. This study showed that the new model had a high prediction. Therefore, this model better stratifies people at high risk of foot ulceration.

U, Shivaram JM, Belehalli P, M. A. S, H. C. C, Sikkandar MY, Brioschi ML. Diabetic Foot Assessment and Care: Barriers and Facilitators in a Cross-Sectional Study in Bangalore, India

(1) Background: This cross-sectional study aims to highlight the assessment and foot care practices in an advanced clinical setting, the clinical characteristics of the patients, and to understand the barriers and facilitators for effective foot care from the perspectives of healthcare practices, resources, and patients' socioeconomic and cultural practices, and other aspects in terms of new technologies for effective foot care such as infrared thermography. (2) Methods: Clinical test data from 158 diabetic patients and a questionnaire to assess the foot care education retention rate were collected at the Karnataka Institute of Endocrinology and Research (KIER) facility. (3) Results: Diabetic foot ulcers (DFUs) were found in 6% of the examined individuals. Male patients were more likely to have diabetes complications, with an odds ratio (OR) of 1.18 (CI = 0.49-2.84). Other diabetes problems raised the likelihood of DFUs by OR 5 (CI = 1.40-17.77). The constraints include socioeconomic position, employment conditions, religious customs, time and cost, and medication non-adherence. The attitude of podiatrists and nurses, diabetic foot education, and awareness protocols and amenities at the facility were all facilitators. (4) Conclusions: Most diabetic foot complications might be avoided with foot care education, regular foot assessments as the standard of treatment, and self-care as a preventive/therapeutic strategy.

Importance of timing optimization for closed-loop applications of vagus nerve stimulation

In recent decades, vagus nerve stimulation (VNS) therapy has become widely used for clinical applications including epilepsy, depression, and enhancing the effects of rehabilitation. However, several questions remain regarding optimization of this therapy to maximize clinical outcomes. Although stimulation parameters such as pulse width, amplitude, and frequency are well studied, the timing of stimulation delivery both acutely (with respect to disease events) and chronically (over the timeline of a disease's progression) has generally received less attention. Leveraging such information would provide a framework for the implementation of next generation closed-loop VNS therapies. In this mini-review, we summarize a number of VNS therapies and discuss (1) general timing considerations for these applications and (2) open questions that could lead to further therapy optimization.

Prevention Strategy for Ulcer Recurrence in Patients with Type II Diabetes Mellitus: A Quasi-Experimental Study

Background

Many strategies exist to prevent diabetic ulcer recurrence, yet an effective method does not currently exist. This study evaluates the effectiveness of a prevention strategy to reduce ulcer recurrence in patients with Diabetes Mellitus (DM).

Materials and Methods

A quasi-experimental, two group study was undertaken with 60 participants with type 2 DM. Two trained nurses participated in this study as study assistants. Participants were divided into two groups: the intervention group received preventive treatment, including examination and assessment, foot care, and an educational program; the control group received standard care using the five pillars of DM management in Indonesia.

Results

An equal number of men (n = 30) and women (n = 30) participated in this study. Neuropathy was noted in 76.70% and 56.70% of patients in the intervention and control groups, respectively. Furthermore, 63.30% of patients in the control group and 56.70% in the intervention group had foot deformities. The recurrence rate was lower in the intervention group (13.30%) than in the control group (33.30%). Moreover, 83.30% in the control group and 76.70% in the intervention group did not smoke. The duration of DM in both groups was >9 years (50% in the intervention and 43.30% in the control group). There were no significant differences between the two groups, with mean (SD) in age (t29 = -0.87, p = 0.389), ankle-brachial index (t29 = -1.05, p = 0.144), and HbA1C (t26 = -0.35, p = 0.733).

Conclusions

Prevention strategies combining examination and assessment, foot care, and educational programs can reduce ulcer recurrence in diabetic patients.

The effect of Tarantula cubensis D6 on zone of stasis in a rat burn model

AIM

Burn injuries are one of the most devastating injuries. Saving the zone of stasis decreases burn size, morbidity, and mortality. Tarantula cubensis (TC) increases epithelization of wounds, and increases wound contraction. In this study, we investigated the effects of TC on the stasis zone.

MATERIALS AND METHODS

36 Wistar albino female rats were divided into 3 groups. Using brass comb burn model, at days 0 and 3, physiological serum solution in group 2, TC injection in group 3and no injection in group 1 was applied. Thermal and normal images were taken on day 10 and rats were sacrificed for histopathological examination.

RESULTS

We found a statistically significant difference between the 1st and 3rd group, 2nd and 3rd group regarding viable wound areas (p < 0.05), temperature difference (body-stasis zone) and mean body temperature (p < 0.05). We found no statistically significant difference between groups regarding neovascularization, inflammatory density, and vital cutaneous appendages. We found a statistically significant difference in epithelial layer thickness between the1st and 3rd groups, 2nd and 3rd groups(p < 0.05).

CONCLUSION

TC increases stasis zone viability macroscopically, increases epithelial layer thickness histopathologically, thus it promotes wound healing in burn wounds. This increase in stasis zone viability was also established with thermal imaging.

Patients, carers and healthcare providers' perspectives on a patient-owned surveillance system for diabetic foot ulcer care: A qualitative study

Objective

Digital health has recently gained a foothold in monitoring and improving diabetes care. We aim to explore the views of patients, carers and healthcare providers (HCPs) regarding the use of a novel patient-owned wound surveillance application as part of outpatient management of patients with diabetic foot ulcers (DFUs).

Methods

Semi-structured online interviews were conducted with patients, carers and HCPs in wound care for DFUs. The participants were recruited from a primary care polyclinic network and two tertiary hospitals in Singapore, within the same healthcare cluster. Purposive maximum variation sampling was used to select participants with differing attributes to ensure heterogeneity. Common themes relating to the wound imaging app were captured.

Results

A total of 20 patients, 5 carers and 20 HCPs participated in the qualitative study. None of the participants have used a wound imaging app before. Regarding a patient-owned wound surveillance app, all were open and receptive to the system and workflow for use in DFU care. Four major themes emerged from patients and carers: (1) technology, (2) application features and usability, (3) feasibility of using the wound imaging application and (4) logistics of care. Four major themes were identified from HCPs: (1) attitudes towards wound imaging app, (2) preferences regarding functionality, (3) perceived challenges for patients/carers and (4) perceived barriers for HCPs.

Conclusion

Our study highlighted several barriers and facilitators from patients, carers and HCPs regarding the use of a patient-owned wound surveillance app. These findings demonstrate the potential of digital health and areas to improve and tailor a DFU wound app suitable for implementation in the local population.

Development of a self-monitoring tool for diabetic foot prevention using smartphone-based thermography: Plantar thermal pattern changes and usability in the home environment

Thermography is a well-known risk-assessment tool for diabetic foot ulcers but is not widely used in the home setting due to the influence of the complicated home environment on thermographic images. This study investigated changes in thermographic images in complicated home environments to determine the feasibility of smartphone-based thermography in home settings. Healthy volunteers (age > 20 years) were recruited and required to take plantar thermal images using smartphone-based thermography attached to a selfie stick at different times of the day for 4 days. The thermal images and associated activities and environmental factors were then analyzed using content analysis. Areas with the highest temperature on the plantar thermal images were described and categorized. Device usability was evaluated using 10-point Likert scales, with 10 representing the highest satisfaction. A total of 140 plantar thermal images from 10 participants were analyzed. In 12 classifications, the three commonest patterns based on the highest temperature location were medial arch (42.1%), whole plantar (10.7%), and forefoot and medial arch (7.9%). The medial arch pattern is most frequently seen after awakening (67.5%) compared to other time points. Device usability was rated 7.5 out of 10 on average. This study was the first to investigate the plantar thermal patterns in the home settings, and the medial arch pattern was the most common hot area, which matches previous findings in well-controlled clinical settings. Therefore, smartphone-based thermography may be feasible as a self-assessment tool in the home setting.

Accuracy comparison study of new smartphone-based semen analyzer versus laboratory sperm quality analyzer

Purpose

This study aimed to test the clinical efficacy of a portable smartphone-based App assisted semen analysis (SA) system, O'VIEW-M PRO® to clinically accurate in comparison with results of laboratory-based conventional semen analyses including manual microscopic and computer-assisted semen analysis (CASA) for self-evaluation of seminal parameters.

Materials and Methods

From January to May 2021, a total of 39 semen samples were analyzed for the sperm concentration and motility with new smartphone-based App assisted semen analyzer, O'VIEW-M PRO®, and results compared with those from laboratory-based manual microscopic SA with Makler Counting Chamber and CASA.

Results

The coefficient factors among the results of the measurement with Makler chamber and laboratory-based CASA comparing to O'VIEW-M PRO® were 0.666 and 0.655 for sperm density, 0.662 and 0.658 for sperm motility, respectively. There were no particular problems with clinical use of the O'VIEW-M PRO®. Device performance in classifying samples is positive (<15×10⁶ sperm/mL) and negative (>15×10⁶ sperm/mL) for sperm concentration criteria, and positive (<40%) and negative (>40%) for sperm motility criteria. The smartphone-based App assisted SA O'VIEW-M PRO® showed a sensitivity of 92.6%, a specificity of 66.7%, and overall accuracy rate of 84.6%.

Conclusions

This study shows a novel smartphone-based App assisted SA system. O'VIEW-M PRO® can easily obtain semen parameter information through self-diagnosis at home and induce infertile men's treatment and help patients after receiving infertile men's treatment before receiving treatment.

Effect of interface pressure and skin surface temperature on pressure injury incidence: a turning schedule pilot study

OBJECTIVE

This study aimed to evaluate the interface pressure and skin surface temperature in relation to the incidence of pressure injury (PI) using three different turning schedules.

METHOD

This was a pilot study with a three-armed randomised clinical trial design. Participants at risk of PI and treated in the high dependency care unit in a regional hospital in Makassar, Indonesia participated in this study. Patients were repositioned at three different turning schedules (two-, three- and four-hourly intervals). Interface pressure measurement and skin surface temperature were measured between 14:00 and 18:00 every three days. The incidence of PI was assessed during the two-week observation period.

RESULTS

A total of 44 participants took part in the study. A one-way ANOVA test revealed no difference in interface pressure among the three different turning schedule groups within two weeks of observations: day zero, p=0.56; day four, p=0.95; day seven, p=0.56; day 10, p=0.63; and day 14, p=0.92. Although the average periumbilical temperature and skin surface temperature were not significant (p>0.05), comparison between these observation sites was significant on all observation days (p<0.05). Regarding the incidence of PI, the proportional hazard test for the development of PI in the three groups was considered not different (hazard ratio: 1.46, 95% confidence interval: 0.43-4.87, p=0.54).

CONCLUSION

No difference in interface pressure and incidence of PI on the three turning schedules was observed; however, there was a potential increase in skin surface temperature in comparison with periumbilical temperature for all three turning schedules.

Prevention of diabetic foot ulcers using a smartphone and mobile thermography: a case study

OBJECTIVE

Early identification of pre-ulcerative pathology is important to preventing diabetic foot ulcers (DFU), but signs of inflammation are difficult to detect on the feet of patients with diabetic neuropathy due to decreased sensation. However, infrared thermography can objectively identify inflammation. Therefore, a device that allows patients to visualise thermograms of their feet might be an effective way to prevent DFU. We aimed to determine the effects of a novel self-monitoring device to prevent DFU using a thermograph attached to a smartphone.

METHOD

A self-monitoring device comprising a mobile thermograph attached to a smartphone on a selfie stick was created, and its effects in two patients with diabetic neuropathy and foot calluses assessed.

RESULTS

For one patient, he understood that walking too much increased the temperature in the skin of his feet (a sign of inflammation). The other patient could not detect high-risk findings, because the temperature of his skin did not increase during the study period.

CONCLUSION

This device might provide self-care incentives to prevent DFU, although some issues, such as the automatic detection of high-risk thermographic changes, need to be improved.

Infrared Thermal Imaging as a Novel Non-Invasive Point-of-Care Tool to Assess Filarial Lymphoedema

Lymphatic filariasis causes disfiguring and disabling lymphoedema, which is commonly and frequently exacerbated by acute dermatolymphangioadenitis (ADLA). Affected people require long-term care and monitoring but health workers lack objective assessment tools. We examine the use of an infrared thermal imaging camera as a novel non-invasive point-of-care tool for filarial lower-limb lymphoedema in 153 affected adults from a highly endemic area of Bangladesh. Temperature differences by lymphoedema stage (mild, moderate, severe) and ADLA history were visualised and quantified using descriptive statistics and regression models. Temperatures were found to increase by severity and captured subclinical differences between no lymphoedema and mild lymphoedema, and differences between moderate and severe stages. Toes and ankle temperatures detected significant differences between all stages other than between mild and moderate stages. Significantly higher temperatures, best captured by heel and calf measures, were found in participants with a history of ADLA, compared to participants who never had ADLA, regardless of the lymphoedema stage. This novel tool has great potential to be used by health workers to detect subclinical cases, predict progression of disease and ADLA status, and monitor pathological tissue changes and stage severity following enhanced care packages or other interventions in people affected by lymphoedema.

Evaluation risk of diabetic foot ulcers (DFUs) using infrared thermography based on mobile phone as advanced risk assessment tool in the community setting: A multisite cross-sectional study

OBJECTIVE

To evaluate the risk of DFUs using infrared thermography based on the mobile phone as an advanced risk assessment tool in the community setting.

METHOD

A multisite cross-sectional study design involving one hundred DM patients in ten health centers in the city of Makassar. Temperature measurement in both feet is done using infrared thermography based on mobile phones in four zones of foot, namely Medial Plantar Artery (MPA), Lateral Plantar Artery (LPA), Medial Calcaneal Artery (MCA) and Lateral Calcaneal Artery (LCA).

RESULTS

The average foot temperature difference was 0.2-1.0°C between the risk groups in the International Working Group of Diabetic Foot (IWGDF) category (p=0.018). The risk zone for DFUs is MPA at risk 0 vs risk 1 (p=0.025), LPA (p=0.020) and MCA (p=0.017) at risk 1 vs risk 2B.

CONCLUSION

Thermography infrared based on the mobile phone can detect early differences in foot temperature within the risk groups.

Thermographic Assessment of Reperfusion Profile Following Using a Tourniquet in Total Knee Arthroplasty: A Prospective Observational Study

Background

Infrared thermal imaging is a non-invasive technique capable of detecting changes in temperature that could ultimately signify changes in blood supply. Flir One is a smartphone-based thermal camera, working by a downloadable application, capable of detecting the limb temperature through a non-contact method using infrared thermography technology. Using the Flir One camera, we will assess the lower limb reperfusion profile following the tourniquet release post total knee arthroplasty (TKA).

Methods

A prospective study included 46 patients who underwent primary TKA. We used the (Flir One Gen 3) thermographic camera to capture images at ankle joint preoperatively, and at 1, 10, and 20 minutes post tourniquet release on operation side. The contralateral ankle stands as control.

Results

The mean preoperative temperature (in Celsius) of ankle control side and operated side were 33.03 (SD=1.65) and 33.26 (SD=1.42), respectively. The mean ankle temperature on operation side was 19.73 (SD=2.85), 30.49 (SD=2), and 32.43 (SD=1.31) at 1, 10, and 20 minutes post tourniquet release, respectively, while the control side showed a mean temperature of 32.85 (SD=1.42), 32.84 (SD=0.91), and 33.15 (SD=0.95) at the same time intervals. There was a significant statistical difference between both ankle temperatures at 1 and 10 minutes (P=0.00 for each time). At 20 minutes, 37 ankles (80.4%) at operation side reached a temperature level similar but below the level of control side; however, the difference was not significant (P=0.692).

Conclusion

Infrared thermography using the smartphone-connected camera is a simple, non-invasive, feasible, and reliable technology. It provides an objective measure to assess the perfusion status of the limbs. In TKA, the distal limb will reach full reperfusion status after approximately 20 minutes of tourniquet release.

Biological characteristics and biomarkers of novel SARS-CoV-2 facilitated rapid development and implementation of diagnostic tools and surveillance measures

Existing coronavirus named as a severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has speeded its spread across the globe immediately after emergence in China, Wuhan region, at the end of the year 2019. Different techniques, including genome sequencing, structural feature classification by electron microscopy, and chest imaging using computed tomography, are primarily used to diagnose and screen SARS-CoV-2 suspected individuals. Determination of the viral structure, surface proteins, and genome sequence has provided a design blueprint for the diagnostic investigations of novel SARS-CoV-2 virus and rapidly emerging diagnostic technologies, vaccine trials, and cell-entry-inhibiting drugs. Here, we describe recent understandings on the spike glycoprotein (S protein), receptor-binding domain (RBD), and angiotensin-converting enzyme 2 (ACE2) and their receptor complex. This report also aims to review recently established diagnostic technologies and developments in surveillance measures for SARS-CoV-2 as well as the characteristics and performance of emerging techniques. Smartphone apps for contact tracing can help nations to conduct surveillance measures before a vaccine and effective medicines become available. We also describe promising point-of-care (POC) diagnostic technologies that are under consideration by researchers for advancement beyond the proof-of-concept stage. Developing novel diagnostic techniques needs to be facilitated to establish automatic systems, without any personal involvement or arrangement to curb an existing SARS-CoV-2 epidemic crisis, and could also be appropriate for avoiding the emergence of a future epidemic crisis.

Point-of-care infrared thermal imaging for differentiating venomous snakebites from non-venomous and dry bites

Background

Local envenomation following snakebites is accompanied by thermal changes, which could be visualized using infrared imaging. We explored whether infrared thermal imaging could be used to differentiate venomous snakebites from non-venomous and dry bites.

Methods

We prospectively enrolled adult patients with a history of snakebite in the past 24 hours presenting to the emergency of a teaching hospital in southern India. A standardized clinical evaluation for symptoms and signs of envenomation including 20-minute whole-blood clotting test and prothrombin time was performed to assess envenomation status. Infrared thermal imaging was done at enrolment, 6 hours, and 24 hours later using a smartphone-based device under ambient conditions. Processed infrared thermal images were independently interpreted twice by a reference rater and once by three novice raters.

Findings

We studied 89 patients; 60 (67%) of them were male. Median (IQR) time from bite to enrolment was 11 (6.5–15) hours; 21 (24%) patients were enrolled within 6 hours of snakebite. In all, 48 patients had local envenomation with/without systemic envenomation, and 35 patients were classified as non-venomous/dry bites. Envenomation status was unclear in six patients. At enrolment, area of increased temperature around the bite site (Hot spot) was evident on infrared thermal imaging in 45 of the 48 patients with envenomation, while hot spot was evident in only 6 of the 35 patients without envenomation. Presence of hot spot on baseline infrared thermal images had a sensitivity of 93.7% (95% CI 82.8% to 98.7%) and a specificity of 82.9% (66.3% to 93.4%) to differentiate envenomed patients from those without envenomation. Interrater agreement for identifying hot spots was more than substantial (Kappa statistic >0.85), and intrarater agreement was almost perfect (Kappa = 0.93). Paradoxical thermal changes were observed in 14 patients.

Conclusions

Point-of-care infrared thermal imaging could be useful in the early identification of non-venomous and dry snakebites.

Most venomous snakebites cause swelling of the bitten body part within a few hours if venom had been injected. Usually, health care providers diagnose venomous snakebites by doing a clinical examination and by testing for incoagulable blood. If no abnormalities are found, then the snakebite is diagnosed as a non-venomous bite or a dry bite. Swelling of the bitten body part results from venom-induced inflammation and is accompanied by local increase in skin temperature. It is possible to capture visual images of these temperature changes by using infrared imaging, the same technology used in night vision cameras. This study found that most persons with venomous snakebites had hot areas on infrared images while such changes were observed in only a few persons with non-venomous or dry snakebites. This new knowledge could help doctors identify non-venomous and dry snakebites early.

A Comprehensive Review of Detection Methods for SARS-CoV-2

Recently, the outbreak of the coronavirus disease 2019 (COVID-19), caused by the SARS-CoV-2 virus, in China and its subsequent spread across the world has caused numerous infections and deaths and disrupted normal social activity. Presently, various techniques are used for the diagnosis of SARS-CoV-2 infection, with various advantages and weaknesses to each. In this paper, we summarize promising methods, such as reverse transcription-polymerase chain reaction (RT-PCR), serological testing, point-of-care testing, smartphone surveillance of infectious diseases, nanotechnology-based approaches, biosensors, amplicon-based metagenomic sequencing, smartphone, and wastewater-based epidemiology (WBE) that can also be utilized for the detection of SARS-CoV-2. In addition, we discuss principles, advantages, and disadvantages of these detection methods, and highlight the potential methods for the development of additional techniques and products for early and fast detection of SARS-CoV-2.

Indocyanine Green Angiography Predicts Tissue Necrosis More Accurately Than Thermal Imaging and Near-Infrared Spectroscopy in a Rat Perforator Flap Model

BACKGROUND

Clinical examination alone is neither sensitive nor specific for predicting flap necrosis, so several technologies, including indocyanine green angiography, thermal imaging (using the FLIR ONE), and near-infrared spectroscopy, have been developed to supplement perfusion assessment. This study aims to compare the accuracy of these three methods for intraoperatively predicting clinical flap necrosis in a rat perforator flap model. The authors hypothesized that near-infrared spectroscopy, assessing oxygenation rather than direct perfusion, would yield significantly different predictions.

METHODS

A 10 × 3-cm epigastric perforator flap was elevated in 14 adult male rats weighing 250 ± 50 g. Flap perfusion was assessed immediately after flap elevation using thermal imaging, near-infrared spectroscopy, and indocyanine green angiography. Measurements were correlated to the clinical endpoint and gold standard of flap necrosis on postoperative day 7.

RESULTS

All three technologies detected significant differences in perfusion along flap length (all p < 0.001), and were associated with significant differences in the odds of developing flap necrosis (all p < 0.001). The areas under the receiver operating characteristic curves were 0.948 for indocyanine green angiography as an absolute value, 0.873 for relative changes with thermal imaging, and 0.792 for tissue oxygenation. The sensitivity, specificity, and accuracy for indocyanine green angiography measured as an absolute value were the highest at 97.8, 87.5, and 92 percent, respectively.

CONCLUSIONS

Indocyanine green angiography most accurately predicted flap necrosis in this study; however, tissue oximetry and thermal imaging were also capable of predicting necrosis and represented potentially less expensive or more readily available alternatives for objective perfusion assessment. Additional research can further delineate their roles and cost-efficacy in clinical practice.

Nanotechnology-Based Approaches for the Detection of SARS-CoV-2

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as a pandemic has been validated as an extreme clinical calamity and has affected several socio-economic activities globally. Proven transmission of this virus occurs through airborne droplets from an infected person. The recent upsurge in the number of infected individuals has already exceeded the number of intensive care beds available to patients. These extraordinary circumstances have elicited the need for the development of diagnostic tools for the detection of the virus and, hence, prevent the spread of the disease. Early diagnosis and effective immediate treatment can reduce and prevent an increase in the number of cases. Conventional methods of detection such as quantitative real-time polymerase chain reaction and chest computed tomography scans have been used extensively for diagnostic purposes. However, these present several challenges, including prolonged assay requirements, labor-intensive testing, low sensitivity, and unavailability of these resources in remote locations. Such challenges urgently require fast, sensitive, and accurate diagnostic techniques for the timely detection and treatment of coronavirus disease 2019 (COVID-19) infections. Point-of-care biosensors that include paper- and chip-based diagnostic systems are rapid, cost-effective, and user friendly. In this article nanotechnology-based potential biosensors for SARS-CoV-2 diagnosis are discussed with particular emphasis on a lateral flow assay, a surface-enhanced Raman scattering-based biosensor, a localized surface plasmon resonance-based biosensor, Förster resonance energy transfer, an electrochemical biosensor, and artificial intelligence-based biosensors. Several biomolecules, such as nucleic acids, antibodies/enzymes, or aptamers, can serve as potential detection molecules on an appropriate platform, such as graphene oxide, nanoparticles, or quantum dots. An effective biosensor can be developed by using appropriate combinations of nanomaterials and technologies.

The Promise of Smartphone Applications in the Remote Monitoring of Postsurgical Wounds: A Literature Review

OBJECTIVE

To review the clinical and scientific literature on remote monitoring and management of postsurgical wounds using smartphone applications (apps).

DATA SOURCES

MEDLINE, PubMed, EMBASE, and Cochrane libraries were searched for relevant articles on patients who received surgery and were monitored postdischarge via an app.

STUDY SELECTION

Articles were selected with the terms "mobile phones," "smartphones," "wounds," "monitor," and "patient preference."

DATA EXTRACTION

The authors found 276 review articles related to telemedicine in wound care. Investigators reviewed the titles and abstracts of the search results and selected 83 articles that were relevant to the remote monitoring of wounds using smartphone apps.

DATA SYNTHESIS

The topics explored in selected literature included smartphone app importance to telemedicine, benefits (medical and financial), app examples, and challenges in the context of wound monitoring and management. The authors identified several challenges and limitations that future studies in the field need to address.

CONCLUSIONS

Remote monitoring and management of wounds using smartphone apps is a valuable technique to enhance the quality of and access to healthcare. However, although some patients may prefer this technology, some lack technological competence, limiting telemedicine's applicability. In addition, issues remain with the reliable interpretation of data collected through apps.

Use of a smartphone thermometer to monitor thermal conductivity changes in diabetic foot ulcers: a pilot study

OBJECTIVE

To investigate the dependability of a thermal gadget connecting to a smartphone. Comparing the exact temperature of damaged tissue with adjacent parts of the limb and to evaluate the changes in thermal conductivity of hard-to-heal wounds in patients with a diabetic foot ulcer (DFU).

METHODS

Potential candidates were divided into three groups and selected from different hospitals in Tehran. Group 1 contained patients with inflammation, Group 2 were patients with vascular complications, and Group 3 were patients who were managing to control their glucose levels to an acceptable level, according to their medical records (i.e. 'healthy cases'). All thermal images were taken without any external stimulus, in room temperature conditions after 15 minutes' rest. All medical records were confirmed by therapeutic supervisors. Moreover, the tissue conditions in patients were considered in the computational part of the study. The temperatures of the ulcer and adjacent tissues were observed and compared. The collected data were used in a suggested model for human tissues and the method of calculation in this study was trial and error. In this study, patients in Group 2 were considered in the computational section of the study.

RESULTS

Temperature difference between the wounds and adjacent tissues for the big toe in three patients in Group 2 was 2.2ºC for the healthier candidate and almost 6.9ºC in the worst case. By comparing the thermal conductivity of normal and damaged tissues, a significant reduction in thermal conductivity was observed for the candidate with the worst status of big toe by about 84.3%. For the other two candidates in this category, it was almost 68.86% and 20.47%.

CONCLUSION

The variation in thermal conductivity represents the change in tissue properties. Thermal conductivity can be applied for early DFU detection. This data may allow introduction of the smartphone thermometer as an authentic and alternative apparatus that is beneficial in diabetic clinics as well as self-assessment by patients. Moreover, due to the decrease in thermal conductivity, this study suggests using intelligent thermal sheets in vulnerable parts of the diabetic foot.

Infrared thermography for monitoring severity and treatment of diabetic foot infections

Monitoring of diabetic foot infections is largely based on clinical assessment, which is limited by moderate reliability. We conducted a prospective study to explore monitoring of thermal asymmetry (difference between mean plantar temperature of the affected and unaffected foot) for the assessment of severity of diabetic foot infections. In patients with moderate or severe diabetic foot infections (International Working Group on the Diabetic Foot infection-grades 3 or 4) we measured thermal asymmetry with an advanced infrared thermography setup during the first 4-5 days of in-hospital treatment, in addition to clinical assessments and tests of serum inflammatory markers (white blood cell counts and C-reactive protein levels). We assessed the change in thermal asymmetry from baseline to final assessment, and investigated its association with infection-grades and serum inflammatory markers. In seven included patients, thermal asymmetry decreased from median 1.8°C (range: -0.6 to 8.4) at baseline to 1.5°C (range: -0.1 to 5.1) at final assessment (P = 0.515). In three patients who improved to infection-grade 2, thermal asymmetry at baseline (median 1.6°C (range: -0.6 to 1.6)) and final assessment (1.5°C (range: 0.4 to 5.1)) remained similar (P = 0.302). In four patients who did not improve to infection-grade 2, thermal asymmetry decreased from median 4.3°C (range: 1.8 to 8.4) to 1.9°C (range: -0.1 to 4.4; P = 0.221). No correlations were found between thermal asymmetry and infection-grades (r = -0.347; P = 0.445), CRP-levels (r = 0.321; P = 0.482) or WBC (r = -0.250; P = 0.589) during the first 4-5 days of hospitalization. Based on these explorative findings we suggest that infrared thermography is of no value for monitoring diabetic foot infections during in-hospital treatment.

Evaluation of infrared technology to detect category I and suspected deep tissue injury in hospitalised patients

OBJECTIVE

To evaluate the use of an infrared thermography device in assessing skin temperature among category I pressure ulcer (PU) and/or suspected deep tissue injuries (SDTI) with intact skin.

METHODS

An observational cross-sectional study design was used. Adult inpatients (cases) who had a category I PU or suspected deep tissue injury (skin intact) on the sacral or heel during the study period (March to April 2018) were recruited. Patients without a PU were also recruited to act as control. Thermal images of the patient's PU site and non-PU site were taken within 24 hours of PU occurrence. Thermal images of the control patients (no PU) were also taken. Each PU case was matched to three control patients in terms of age, gender, race and anatomical sites. All thermal images were taken using a portable CAT S60 Thermal Imaging Rugged Smartphone (Caterpillar Inc., US) that provided readings of the skin temperature in degrees Celsius.

RESULTS

A total of 17 cases and 51 controls were recruited. Among the cases, the mean difference in skin temperature between the PU site (mean: 31.14°C; standard deviation [SD]: 1.54) and control site within the cases (mean: 28.93°C; SD: 3.47) was significant (difference: 2.21±3.66°C; p=0·024). When comparing between all cases and controls, the mean temperature difference was non-significant. When comparing between the category I PU and suspected deep pressure injury cases, the mean difference was also non-significant.

CONCLUSION

Using infrared thermography technology at the bedside to measure skin temperature will support the clinical diagnosis of patients with skin types I to III. However, there is a need for a more accurate and objective measurement to identify and diagnose early category I PU or suspected deep tissue injury in adult patients with darker skin types 4 and above, enabling early initiation of preventive measures in the hospital acute care setting.

Diagnosing COVID-19: The Disease and Tools for Detection

COVID-19 has spread globally since its discovery in Hubei province, China in December 2019. A combination of computed tomography imaging, whole genome sequencing, and electron microscopy were initially used to screen and identify SARS-CoV-2, the viral etiology of COVID-19. The aim of this review article is to inform the audience of diagnostic and surveillance technologies for SARS-CoV-2 and their performance characteristics. We describe point-of-care diagnostics that are on the horizon and encourage academics to advance their technologies beyond conception. Developing plug-and-play diagnostics to manage the SARS-CoV-2 outbreak would be useful in preventing future epidemics.

Post-operative monitoring of free flaps using a low-cost thermal camera: a pilot study

Background

Careful post-operative monitoring of free flaps is important in flap survival; immediate action increases flap salvage rate. Although various methods are available, room for improvement remains. Thermal cameras have proven their value in medicine and are nowadays readily available at low costs. The objective of this study was to evaluate the potential of an affordable infrared thermal camera and software in the detection of failing free flaps during post-operative monitoring.

Methods

Free myocutaneous rectus abdominis flaps were harvested in 16 female landrace pigs and replanted after several hours of storage. All flaps were assessed with indocyanine green fluorescence angiography as well as hourly clinical assessment of skin colour, turgor and capillary refill. Furthermore, thermal photographs were taken simultaneously with the FLIR One thermal camera smartphone module. These photographs were processed in MATLAB and evaluated on their additional value as an indicator for flap failure.

Results

Out of 16 flaps, three flaps failed due to arterial failure and one flap developed venous congestion. The mean flap temperature compared to adjacent control skin proved to be most indicative for flap failure. All unsuccessful flaps showed lower temperatures after failure compared to the uncompromised free flaps.

Conclusions

An affordable thermal camera module can potentially contribute to post-operative free flap monitoring. Vascular compromise in free flaps can be distinguished by investigating relative temperature differences between the flap and reference skin. Until the FLIR One camera has been extensively investigated in a human population, it should be used in conjunction with conventional monitoring techniques.

Level of evidence: Level IV, diagnostic study

Smartphone-Based Device in Exotic Pet Medicine

This article reviews the use of the smartphone in exotic pet medicine. The mobile app is the most instinctive use of the smartphone; however, there are very limited software dedicated to the exotic pet specifically. With an adapter, the smartphone can be attached to a regular endoscope and acts as a small endoscopic unit. Additional devices, such as infrared thermography or ultrasound, can be connected to the smartphone through the micro-USB port. The medical use of the smartphone is still in its infancy in veterinary medicine but can bring several solutions to the exotic pet practitioner and improve point-of-care evaluation.

Use of FLIR ONE Smartphone Thermography in Burn Wound Assessment

OBJECTIVE

Forward-looking infrared (FLIR) thermography technology uses a handheld camera that measures skin infrared emissivity, captures photographs, and can be analyzed through specialized software. Forward-looking infrared images can be used to analyze and correlate burn wound temperature with burn depth, burn progression, and the number of days needed for healing. FLIR ONE is a miniature, smartphone-compatible thermal imaging camera that has been used to assess inflammation in diabetic foot ulcers, as well as locating perforators in flap surgery. However, FLIR ONE's reliability in burn wound assessment has not been evaluated. This case series investigates the accuracy of FLIR ONE in comparison with the widely used indocyanine green (ICG) angiography in assessing burn wounds.

METHODS

Five acute third-degree burn wounds were assessed using ICG angiography and FLIR ONE imaging (infrared thermography) to determine burn extent before surgical intervention. Patients were taken to the operating room within 48 hours of presentation; FLIR ONE images were captured approximately 35 to 45 cm above the wound surface. Margins of unsalvageable tissue as determined by ICG and FLIR ONE were marked and compared.

RESULTS

The area of unsalvageable tissue as determined by FLIR ONE closely corresponded to the area determined by ICG. FLIR ONE overestimated unsalvageable tissue margins by approximately 1 to 2 cm. The area estimated by ICG consistently overlapped with more than 90% of the area estimated by FLIR ONE.

CONCLUSIONS

There is a strong correlation between FLIR ONE and ICG when assessing salvageable tissue in third-degree burn wounds. FLIR ONE maximizes the convenience and cost-effectiveness of infrared thermography technology but may overestimate unsalvageable tissue area. FLIR ONE is promising as an adjunct to current imaging modalities such as ICG but requires further study for comparison.

Plasmonic Photothermal Nanoparticles for Biomedical Applications

Recent advances of plasmonic nanoparticles include fascinating developments in the fields of energy, catalyst chemistry, optics, biotechnology, and medicine. The plasmonic photothermal properties of metallic nanoparticles are of enormous interest in biomedical fields because of their strong and tunable optical response and the capability to manipulate the photothermal effect by an external light source. To date, most biomedical applications using photothermal nanoparticles have focused on photothermal therapy; however, to fully realize the potential of these particles for clinical and other applications, the fundamental properties of photothermal nanoparticles need to be better understood and controlled, and the photothermal effect-based diagnosis, treatment, and theranostics should be thoroughly explored. This Progress Report summarizes recent advances in the understanding and applications of plasmonic photothermal nanoparticles, particularly for sensing, imaging, therapy, and drug delivery, and discusses the future directions of these fields.

Value of Infrared Thermography Camera Attached to a Smartphone for Evaluation and Follow-up of Patients with Graves' Ophthalmopathy

PURPOSE

Graves' ophthalmopathy (GO) is the most common extra-thyroid manifestation of Graves' disease (GD). The Clinical Activity Score (CAS) has been widely used to evaluate GO inflammation severity and response to treatment; however, it is quite subjective. Infrared thermography (IRT) is a portable and low-cost device to evaluate local temperature and assess inflammation. The aim was to evaluate ocular temperature by IRT as an instrument for measuring inflammatory activity in GO and its correlation with CAS.

METHODS

This is a cross-sectional study involving 136 consecutive GD patients (12 with CAS ≥ 3/7, 62 with CAS < 3 and 62 without apparent GO) with 62 healthy controls. Patients with active ophthalmopathy were prospectively evaluated. Exophthalmometry, CAS, and thermal images from caruncles and upper eyelids were acquired from all subjects.

RESULTS

All eye areas of thermal evaluation had higher temperatures in GD patients with active ophthalmopathy (caruncles, p<0.0001; upper eyelids, p<0.0001), and it was positively correlated with CAS (r=0.60 and p<0.0001 at caruncles; r=0.58 and p<0.0001 at upper eyelids). No difference in temperature was found between other groups. Patients with active ophthalmopathy were prospectively evaluated after 6 or 12 months of the treatment and a significant difference was found in ophthalmometry (p=0.0188), CAS (p=0.0205), temperature of caruncles (p=0.0120), and upper eyelids (p=0.0066).

CONCLUSIONS

IRT was an objective and simple tool for evaluation and follow-up of inflammation in GO, allowed evidencing patients with significant inflammatory activity, and had a good correlation with the CAS score.

Validation of low-cost smartphone-based thermal camera 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.

Infrared thermography in the diagnosis and management of vasculitis

Vasculitis is a clinical condition with associated diagnostic challenges due to nonspecific symptoms and lack of a confirmatory imaging modality. We report a case of a 39-year-old female patient who developed generalized malaise, lethargy, and headache. Laboratory evaluation showed elevated inflammatory markers. Conventional imaging studies including computed tomography and carotid duplex ultrasound were unremarkable. Infrared thermography revealed enhanced thermographic signals in the left carotid artery and aortic arch. Corticosteroid therapy was commenced, and the patient responded well. Follow-up infrared thermography at 6 months showed complete resolution of the thermographic pattern, and the patient remained symptom free.

Pressure injury identification, measurement, coding, and reporting: Key challenges and opportunities

Pressure injury (PI) rates are a commonly used indicator of performance of health care facilities, both in acute and subacute settings. However, measuring PI rates in an accurate and reproducible fashion has been challenging. The consequences of poor measurement may include failure to identify poorly performing institutions or incorrect accusations of poor quality care. In this article, we describe the main challenges in identification, coding, and reporting of PIs. Issues include inconsistent identification of PIs at the time of admission, variations in the intensity of PI detection, and differing approaches to coding and the adjustment for differing risks amongst different patient population. These are compounded by differences in the epidemiological approach because rates will differ according to whether patients are surveyed cross-sectionally (eg, on a set day per month) or if the survey is undertaken at discharge. In some cases, financial incentives may also influence PI reporting. We also discuss potential strategies for improving data collection and benchmarking as an aid to reducing PI prevalence.

The validity and reliability of remote diabetic foot ulcer assessment using mobile phone images

Despite their potential for telemedicine in diabetic foot ulcer treatment, diagnostic accuracy of assessment of diabetic foot ulcers using mobile phone images is unknown. Our aim was to determine the validity and reliability of remote diabetic foot ulcer assessment using mobile phone images. Fifty diabetic foot ulcers were assessed live and photographed. Five independent observers remotely assessed the mobile phone images twice for presence of nine clinical characteristics and three treatment decisions. Positive likelihood (LLR+) and negative likelihood (LLR−) ratios were calculated for validity. Multirater Randolph’s and bi-rater Bennet kappa values were calculated for reliability. LLR+ ranged from 1.3–4.2; LLR− ranged from 0.13–0.88; the treatment decision ‘peri-wound debridement’ was the only item with ‘strong diagnostic evidence’. Inter-observer reliability kappa ranged from 0.09–0.71; test-retest reliability from 0.45–0.86; the treatment decision ‘peri-wound debridement’ was the only item with ‘adequate agreement’. In conclusion, mobile phone images had low validity and reliability for remote assessment of diabetic foot ulcers and should not be used as a stand-alone diagnostic instrument. Clinicians who use mobile phone images in clinical practice should obtain as much additional information as possible when making treatment decisions based on these images, and be cautious of the low diagnostic accuracy.

Point-of-care wound visioning technology: Reproducibility and accuracy of a wound measurement app

BACKGROUND

Current wound assessment practices are lacking on several measures. For example, the most common method for measuring wound size is using a ruler, which has been demonstrated to be crude and inaccurate. An increase in periwound temperature is a classic sign of infection but skin temperature is not always measured during wound assessments. To address this, we have developed a smartphone application that enables non-contact wound surface area and temperature measurements. Here we evaluate the inter-rater reliability and accuracy of this novel point-of-care wound assessment tool.

METHODS AND FINDINGS

The wounds of 87 patients were measured using the Swift Wound app and a ruler. The skin surface temperature of 37 patients was also measured using an infrared FLIR™ camera integrated with the Swift Wound app and using the clinically accepted reference thermometer Exergen DermaTemp 1001. Accuracy measurements were determined by assessing differences in surface area measurements of 15 plastic wounds between a digital planimeter of known accuracy and the Swift Wound app. To evaluate the impact of training on the reproducibility of the Swift Wound app measurements, three novice raters with no wound care training, measured the length, width and area of 12 plastic model wounds using the app. High inter-rater reliabilities (ICC = 0.97-1.00) and high accuracies were obtained using the Swift Wound app across raters of different levels of training in wound care. The ruler method also yielded reliable wound measurements (ICC = 0.92-0.97), albeit lower than that of the Swift Wound app. Furthermore, there was no statistical difference between the temperature differences measured using the infrared camera and the clinically tested reference thermometer.

CONCLUSIONS

The Swift Wound app provides highly reliable and accurate wound measurements. The FLIR™ infrared camera integrated into the Swift Wound app provides skin temperature readings equivalent to the clinically tested reference thermometer. Thus, the Swift Wound app has the advantage of being a non-contact, easy-to-use wound measurement tool that allows clinicians to image, measure, and track wound size and temperature from one visit to the next. In addition, this tool may also be used by patients and their caregivers for home monitoring.

Dedicated tool to assess the impact of a rhetorical task on human body temperature

INTRODUCTION

Functional infrared thermal imaging is a method widely used in medicine, including analysis of the mechanisms related to the effect of emotions on physiological processes. The article shows how the body temperature may change during stress associated with performing a rhetorical task and proposes new parameters useful for dynamic thermal imaging measurements MATERIALS AND METHODS: 29 healthy male subjects were examined. They were given a rhetorical task that induced stress. Analysis and processing of collected body temperature data in a spatial resolution of 256×512pixels and a temperature resolution of 0.1°C enabled to show the dynamics of temperature changes. This analysis was preceded by dedicated image analysis and processing methods RESULTS: The presented dedicated algorithm for image analysis and processing allows for fully automated, reproducible and quantitative assessment of temperature changes and time constants in a sequence of thermal images of the patient. When performing the rhetorical task, the temperature rose by 0.47±0.19°C in 72.41% of the subjects, including 20.69% in whom the temperature decreased by 0.49±0.14°C after 237±141s. For 20.69% of the subjects only a drop in temperature was registered. For the remaining 6.89% of the cases, no temperature changes were registered CONCLUSIONS: The performance of the rhetorical task by the subjects causes body temperature changes. The ambiguous temperature response to the given stress factor indicates the complex mechanisms responsible for regulating stressful situations. Stress associated with the examination itself induces body temperature changes. These changes should always be taken into account in the analysis of infrared data.

Infrared thermal imaging in connective tissue diseases

Infrared thermal imaging (IRT) is a non-invasive, non-contact technique which allows one to measure and visualize infrared radiation. In medicine, thermal imaging has been used for more than 50 years in various clinical settings, including Raynaud’s phenomenon and systemic sclerosis. Imaging and quantification of surface body temperature provides an indirect measure of the microcirculation’s overall performance. As such, IRT is capable of confirming the diagnosis of Raynaud’s phenomenon, and, with additional cold or heat challenge, of differentiating between the primary and secondary condition. In systemic sclerosis IRT has a potential role in assessing disease activity and monitoring treatment response. Despite certain limitations, thermal imaging can find a place in clinical practice, and with the introduction of small, low-cost infrared cameras, possibly become a part of routine rheumatological evaluation.

Novel device for male infertility screening with single-ball lens microscope and smartphone

OBJECTIVE

To investigate the usefulness of a novel semen analysis device consisting of a single-ball lens microscope paired with a state-of-the-art smartphone equipped with a camera.

DESIGN

Laboratory investigation.

SETTING

University research laboratory.

PATIENT(S)

A total of 50 semen samples obtained from volunteers were analyzed for count, concentration, and motility with an 0.8-mm ball lens and three types of smartphone. Comparisons were made with results obtained with a laboratory-based computer-assisted sperm analysis (CASA) system.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Sperm concentration; sperm motility.

RESULT(S)

Sperm concentration counted with a ball lens and each smartphone showed a very strong correlation with the CASA results. Likewise, sperm motility calculated with our device showed significant correlations to CASA. If eight spermatozoa or fewer were found on the field of view of an iPhone 6s, the semen specimens were considered to be below the lower reference limit for sperm concentration of World Health Organization 2010 guidelines (15 × 10(6) spermatozoa/mL). The sensitivity was 87.5%, and specificity was 90.9%.

CONCLUSION(S)

Smartphones have great potential to analyze semen because they are portable, contain excellent digital cameras, and can be easily attached to a microscope. A single-ball lens microscope is inexpensive and easy to use for acquiring digital microscopic movies. Given its small size and weight, the device can support testing for male fertility at home or in the field, making it much more convenient and economical than current practice. This single-ball lens microscope provides an easy solution for global users to rapidly screen for male infertility.