A New Smartphone-Based Method for Wound Area Measurement

Comparison of digital and traditional skin wound closure assessment methods in mice

BACKGROUND

Chronic skin wounds are a common complication of many diseases such as diabetes. Various traditional methods for assessing skin wound closure are used in animal studies, including wound tracing, calliper measurements and histological analysis. However, these methods have poorly defined wound closure or practical limitations. Digital image analysis of wounds is an increasingly popular, accessible alternative, but it is unclear whether digital assessment is consistent with traditional methods. This study aimed to optimise and compare digital wound closure assessment with traditional methods, using a diabetic mouse model. Diabetes was induced in male C57BL/6J mice by high-fat diet feeding combined with low dose (65 mg/kg of body weight) streptozotocin injections. Mice fed normal chow were included as controls. After 18 weeks, four circular full-thickness dorsal skin wounds of 4 mm diameter were created per mouse. The wounds were photographed and measured by callipers. Wound closure rate (WCR) was digitally assessed by two reporters using two methods: wound outline (WCR-O) and re-epithelialisation (WCR-E). Wounded skin tissues were collected at 10-days post-wounding and wound width was measured from haematoxylin and eosin-stained skin tissue.

RESULTS

Between reporters, WCR-O was more consistent than WCR-E, and WCR-O correlated with calliper measurements. Histological analysis supported digital assessments, especially WCR-E, when wounds were histologically closed.

CONCLUSIONS

WCR-O could replace calliper measurements to measure skin wound closure, but WCR-E assessment requires further refinement. Small animal studies of skin wound healing can greatly benefit from standardised definitions of wound closure and more consistent digital assessment protocols.

Data-driven digital health technologies in the remote clinical care of diabetic foot ulcers: a scoping review

Background

The availability and effectiveness of Digital Health Technologies (DHTs) to support clinicians, empower patients, and generate economic savings for national healthcare systems are growing rapidly. Of particular promise is the capacity of DHTs to autonomously facilitate remote monitoring and treatment. Diabetic Foot Ulcers (DFUs) are characterised by high rates of infection, amputation, mortality, and healthcare costs. With clinical outcomes contingent on activities that can be readily monitored, DFUs present a promising focus for the application of remote DHTs.

Objective

This scoping review has been conducted as a first step toward ascertaining fthe data-related challenges and opportunities for the development of more comprehensive, integrated, and individualised sense/act DHTs. We review the latest developments in the application of DHTs to the remote care of DFUs. We cover the types of DHTs in development and their features, technological readiness, and scope of clinical testing.

Eligibility criteria

Only peer-reviewed original experimental and observational studies, case series and qualitative studies were included in literature searches. All reviews and manuscripts presenting pre-trial prototype technologies were excluded.

Methods

An initial search of three databases (Web of Science, MEDLINE, and Scopus) generated 1,925 English-language papers for screening. 388 papers were assessed as eligible for full-text screening by the review team. 81 manuscripts were found to meet the eligibility criteria.

Results

Only 19% of studies incorporated multiple DHTs. We categorised 56% of studies as 'Treatment-Manual', i.e. studies involving technologies aimed at treatment requiring manual data generation, and 26% as 'Prevention-Autonomous', i.e. studies of technologies generating data autonomously through wearable sensors aimed at ulcer prevention through patient behavioural change. Only 10% of studies involved more ambitious 'Treatment-Autonomous' interventions. We found that studies generally reported high levels of patient adherence and satisfaction.

Conclusions

Our findings point to a major potential role for DHTs in remote personalised medical management of DFUs. However, larger studies are required to assess their impact. Here, we see opportunities for developing much larger, more comprehensive, and integrated monitoring and decision support systems with the potential to address the disease in a more complete context by capturing and integrating data from multiple sources from subjective and objective measurements.

Comparison of Digital Planimetry and Ruler Methods for the Measurement of Extraction Socket Wounds

Background and objectives: The purpose of the study was to evaluate and compare ruler and digital planimetry methods to measure extraction socket wounds. Materials and Methods: In total, 41 extraction socket wounds were selected for assessment of wound area by ruler and digital planimetry methods. In the simple ruler method, the periodontal probe was utilized to measure the length and breadth of the extraction wound, whereas in the digital planimetry technique, Pictzar software was used. Data were analyzed using R software version 4.1.1 and Excel. For intergroup comparisons of wound surface area, Welch t-tests were used, and paired t-tests were used for intragroup comparisons. Intra-class correlation coefficients (ICC) and 95% confidence intervals (CIs) were used to evaluate the inter-method reliabilities of surface area. Results: Both ruler and digital planimetry techniques showed post-operative reductions in surface area. A significant difference was reported between the two techniques; however, the ruler method measurements were overestimated compared to those obtained with digital planimetry. Conclusions: This study concludes that digital planimetry techniques provide more accurate results when compared with the simple ruler method.

The role of artificial intelligence technology in the care of diabetic foot ulcers: the past, the present, and the future

Foot ulcers are common complications of diabetes mellitus and substantially increase the morbidity and mortality due to this disease. Wound care by regular monitoring of the progress of healing with clinical review of the ulcers, dressing changes, appropriate antibiotic therapy for infection and proper offloading of the ulcer are the cornerstones of the management of foot ulcers. Assessing the progress of foot ulcers can be a challenge for the clinician and patient due to logistic issues such as regular attendance in the clinic. Foot clinics are often busy and because of manpower issues, ulcer reviews can be delayed with detrimental effects on the healing as a result of a lack of appropriate and timely changes in management. Wound photographs have been historically useful to assess the progress of diabetic foot ulcers over the past few decades. Mobile phones with digital cameras have recently revolutionized the capture of foot ulcer images. Patients can send ulcer photographs to diabetes care professionals electronically for remote monitoring, largely avoiding the logistics of patient transport to clinics with a reduction on clinic pressures. Artificial intelligence-based technologies have been developed in recent years to improve this remote monitoring of diabetic foot ulcers with the use of mobile apps. This is expected to make a huge impact on diabetic foot ulcer care with further research and development of more accurate and scientific technologies in future. This clinical update review aims to compile evidence on this hot topic to empower clinicians with the latest developments in the field.

Digital Planimetry With a New Adaptive Calibration Procedure Results in Accurate and Precise Wound Area Measurement at Curved Surfaces

BACKGROUND

The purpose of this study was to determine the accuracy of wound area measurement at a curved surface using a digital planimetry (DP) with the newly proposed adaptive calibration.

METHODS

Forty wound shapes were printed and placed at the side surfaces of cylinders with diameters of 9.4 and 6.2 cm. Area measurements were carried out using a commercial device SilhouetteMobile (Aranz, New Zealand) and the planimetric app Planimator. Planimetric area measurements were carried out using 2 one-dimensional calibration markers placed above and below the wound shape. The method of adaptive calibration for DP was described. Reference area values of wound shapes were obtained by pixel counting on digital scans made with an optical scanner. Relative errors (REs) and relative differences (RDs) for area measurements were analyzed.

RESULTS

The median of REs for the DP with adaptive calibration (DPwAC) was equal to 0.60% and was significantly smaller than the median for the SilhouetteMobile device (SMD) (2.65%), and significantly smaller than the median for the DP (2.23%). The SD of RDs for the DPwAC of 0.87% was considerably lower than for the SMD (6.45%), and for the DP without adaptive calibration (2.51%). The mean of RDs for the DPwAC (0.082%) was not significantly different from zero, which means that the systematic error was not present for the DPwAC.

CONCLUSIONS

The use of the adaptive calibration in DP to measure the areas at curved surface resulted in a significant increase of accuracy and precision, and removal of systematic error. The DPwAC revealed 4.4 times lower error and 7.4 times higher precision of area measurement at curved surfaces than the SMD.

Wound Size Imaging: Ready for Smart Assessment and Monitoring

Significance: We introduce and evaluate emerging devices and modalities for wound size imaging and also promising image processing tools for smart wound assessment and monitoring. Recent Advances: Some commercial devices are available for optical wound assessment but with limited possibilities compared to the power of multimodal imaging. With new low-cost devices and machine learning, wound assessment has become more robust and accurate. Wound size imaging not only provides area and volume but also the proportion of each tissue on the wound bed. Near-infrared and thermal spectral bands also enhance the classical visual assessment. Critical Issues: The ability to embed advanced imaging technology in portable devices such as smartphones and tablets with tissue analysis software tools will significantly improve wound care. As wound care and measurement are performed by nurses, the equipment needs to remain user-friendly, enable quick measurements, provide advanced monitoring, and be connected to the patient data management system. Future Directions: Combining several image modalities and machine learning, optical wound assessment will be smart enough to enable real wound monitoring, to provide clinicians with relevant indications to adapt the treatments and to improve healing rates and speed. Sharing the wound care histories of a number of patients on databases and through telemedicine practice could induce a better knowledge of the healing process and thus a better efficiency when the recorded clinical experience has been converted into knowledge through deep learning.

A pilot feasibility randomised clinical trial comparing dialkylcarbamoylchloride-coated dressings versus standard care for the primary prevention of surgical site infection

A surgical site infection (SSI) may occur in up to 30% of procedures and results in significant morbidity and mortality. We aimed to assess the feasibility of conducting a randomised controlled trial (RCT) examining the use of dialkylcarbamoylchloride (DACC)‐impregnated dressings, which bind bacteria at the wound bed, in the prevention of SSI in primarily closed incisional wounds. This pilot RCT recruited patients undergoing clean or clean‐contaminated vascular surgery. Participants were randomised intraoperatively on a 1:1 basis to either a DACC‐coated dressing or a control dressing. Outcomes were divided into feasibility and clinical outcomes. The primary clinical outcome was SSI at 30 days (assessed using Centers for Disease Control criteria and Additional treatment, Serous discharge, Erythema, Purulent exudate, Separation of the deep tissues, Isolation of bacteria and duration of inpatient Stay scoring methods). This study recruited 144 patients in 12 months at a median rate of 10 per month. Eligibility was 73% and recruitment 60%. At 30 days, there was a 36.9% relative risk reduction in the DACC‐coated arm (16.22% versus 25.71%, odds ratio 0.559, P = 0.161). The number needed to treat was 11 patients. A large‐scale RCT is both achievable and desirable given the relative risk reduction shown in this study. Further work is needed to improve the study protocol and involve more centres in a full‐scale RCT.

Measuring Surface Area of Skin Lesions with 2D and 3D Algorithms

Purpose

The treatment of skin lesions of various kinds is a common task in clinical routine. Apart from wound care, the assessment of treatment efficacy plays an important role. In this paper, we present a new approach to measure the skin lesion surface in two and three dimensions.

Methods

For the 2D approach, a single photo containing a flexible paper ruler is taken. After semi-automatic segmentation of the lesion, evaluation is based on local scale estimation using the ruler. For the 3D approach, reconstruction is based on Structure from Motion. Roughly outlining the region of interest around the lesion is required for both methods.

Results

The measurement evaluation was performed on 117 phantom images and five phantom videos for 2D and 3D approach, respectively. We found an absolute error of 0.99±1.18  cm² and a relative error 9.89± 9.31% for 2D. These errors are <1  cm² and <5% for five test phantoms in our 3D case. As expected, the error of 2D surface area measurement increased by approximately 10% for wounds on the bent surface compared to wounds on the flat surface. Using our method, the only user interaction is to roughly outline the region of interest around the lesion.

Conclusions

We developed a new wound segmentation and surface area measurement technique for skin lesions even on a bent surface. The 2D technique provides the user with a fast, user-friendly segmentation and measurement tool with reasonable accuracy for home care assessment of treatment. For 3D only preliminary results could be provided. Measurements were only based on phantoms and have to be repeated with real clinical data.

Use of Smartphones for Clinical and Medical Education

Smartphone use in clinical settings and in medical education has been on the rise, benefiting both health care and health care providers. Studies have shown, however, that some health care facilities and providers are reluctant to switch to smartphones due to the threat of mixing personal apps with clinical care applications and the possibility that distraction created by smartphone use could lead to medication errors and errors linked to procedures, treatments, or tests. The purpose of this research was to examine the effects of smartphones in a clinical setting and for medical education, to determine their overall impact. The methodology for this qualitative study was a literature review, conducted over five electronic databases. The search was limited to articles published in English, between 2010 and 2016. Forty-one sources that focused on the implementation of and the barriers to use of smartphones in clinical and medical education environments were referenced. These studies revealed that smartphones have more positive than negative effects on the ability to enhance patient care and medical education. Smartphone use is clearly an effective and efficient method of enhancing patient care and medical education in the health care industry. Access to health care as well is enhanced by the use of this tool.

Health Sensors, Smart Home Devices, and the Internet of Medical Things: An Opportunity for Dramatic Improvement in Care for the Lower Extremity Complications of Diabetes

OBJECTIVE

The prevalent and long-neglected diabetic foot ulcer (DFU) and its related complications rank among the most debilitating and costly sequelae of diabetes. With the rise of the Internet of medical things (IoMT), along with smart devices, the med-tech industry is on the cusp of a home-care revolution, which could also create opportunity for developing effective solutions with significant potential to reduce DFU-associated costs and saving limbs. This article discusses potential applications of IoMT to the DFU patient population and beyond.

METHODS

To better understand potential opportunities and challenges associated with implementing IoMT for management of DFU, the authors reviewed recent relevant literatures and included their own expert opinions from a multidisciplinary point of view including podiatry, engineering, and data security.

RESULTS

The IoMT has opened digital transformation of home-based diabetic foot care, as it enables promoting patient engagement, personalized care and smart management of chronic and noncommunicable diseases through individual data-driven treatment regimens, telecommunication, data mining, and comprehensive feedback tailored to individual requirements. In particular, with recent advances in voice-activated commands technology and its integration as a part of IoMT, new opportunities have emerged to improve the patient's central role and responsibility in enabling an optimized health care ecosystem.

CONCLUSIONS

The IoMT has opened new opportunities in health care from remote monitoring to smart sensors and medical device integration. While it is at its early stage of development, ultimately we envisage a connected home that, using voice-controlled technology and Bluetooth-radio-connected add-ons, may augment much of what home health does today.

Ways to increase precision and accuracy of wound area measurement using smart devices: Advanced app Planimator

Introduction

Wound surface area measurement is important as therapeutic decisions may depend on the change of wound surface area over time. Digital planimetry is a popular technique in wound area measurement. It is accurate and repeatable when calibration is performed with 2 rulers placed at opposite sides of a wound. The aim of the current study was improving accuracy and precision of wound area measurement using capabilities of smart devices.

Methods

The correction of area measurement based on calculated camera tilt angle and the calculation of calibration coefficient of linear dimensions as weighted average were proposed. These and other improvements were applied in the Planimator app for Android, which was then used in the study. Accuracy and precision of the Planimator app were compared to the Visitrak device, the SilhouetteMobile device, the AreaMe software, and to the digital planimetry based on 2-ruler calibration with pictures taken by the smartphone, compact, and D-SLR cameras. Areas of 40 wound shapes of area ranged from 0.14 to 31.72 cm² were measured with each device. Medians of relative errors (REs) were compared in the accuracy tests and standard deviations (SDs) of relative differences (RDs) were compared in the tests of precision.

Results

The median of REs for the Planimator app was not significantly different from the medians of REs for the digital planimetry based on pictures from the compact or D-SLR cameras, but it was significantly lower than the medians of REs for the Visitrak and SilhouetteMobile devices, the AreaMe software and the digital planimetry based on pictures from a smartphone camera. The SD of RDs for the Planimator app was not significantly different from the SDs of RDs for the digital planimetry based on pictures from the compact or D-SLR cameras, but it was significantly lower than the SDs of RDs for the Visitrak and SilhouetteMobile devices, the AreaMe software and the digital planimetry based on pictures from a smartphone camera. The Planimator app installed at a smartphone revealed to be 2-fold more accurate and 1.5-fold more precise than the measurements with using ImageJ software based on pictures taken with the same smartphone.

Conclusions

The Planimator app occurred to have the same accuracy and precision as measurements with digital planimetry with 2-ruler calibration and based on pictures from a compact camera or a D-SLR camera. This app showed better accuracy and precision than the Visitrak and SilhouetteMobile devices, the AreaMe software and the digital planimetry based on pictures from a smartphone camera.

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.

Diagnostic and Prognostic Utility of Non-Invasive Multimodal Imaging in Chronic Wound Monitoring: a Systematic Review

Monitoring chronic wound [CW] healing is a challenging issue for clinicians across the world. Moreover, the health and cost burden of CW are escalating at a disturbing rate due to a global rise in population of elderly and diabetic cases. The conventional approach includes visual contour, sketches, or more rarely tracings. However, such conventional techniques bring forth infection, pain, allergies. Furthermore, these methods are subjective as well as time-consuming. As such, nowadays, non-touching and non-invasive CW monitoring system based on imaging techniques are gaining importance. They not only reduce patients' discomfort but also provide rapid wound diagnosis and prognosis. This review provides a survey of different types of CW characteristics, their healing mechanism and the multimodal non-invasive imaging methods that have been used for their diagnosis and prognosis. Current clinical practices as well as personal health systems [m-health and e-health] for CW monitoring have been discussed.

Nontraditional Methods to Evaluate Wound Healing

BACKGROUND

Traditional evaluation of wound healing is sometimes subjective. It is necessary to develop qualitative and quantitative methods to enable more efficient and accurate evaluation of wounds. Recently, new techniques have been introduced and the correspondence between these techniques and clinician judgment is critical.

OBJECTIVE

Some nontraditional techniques that analyze wound healing were reviewed, which include measurements of the wound area, tissue color, skin barrier function, skin humidity, and keratinocyte morphology.

METHODS

This review article is based on medical research that focuses on the evaluation of wound healing.

RESULTS

Software-based and advanced device-based techniques generally provide more accurate and precise results than traditional ones, such as the ruler-based technique. Measurement of tissue color can also help to identify the type of tissue. Evaluation of skin barrier function can assist clinicians to analyze functional restoration of skin, whereas skin humidity demonstrates the exudate production status of the wound. In addition, keratinocyte morphology in the wound bed indicates quality of wound healing and side effects of treatment.

CONCLUSION

There is no gold standard method for qualitative and quantitative evaluation of wound healing. It is important to understand the type of wound, sample size, results obtained, advantages, and limitations of each technique.

BIOPSY 1-2-3 in Dermatologic Surgery: Improving Smartphone use to Avoid Wrong-Site Surgery

The smartphone has become a ubiquitous tool in modern culture. Given the current high quality of smartphone cameras, they should be considered a valuable tool for the dermatologic surgeon in the pre-operative consultation. The purpose of this technical note is to describe a methodology using smartphone camera technology to improve the process for capturing biopsy site photographs and including those photos in decision making to maximize cutaneous surgical outcomes. This technical note describes a three-step procedure (BIOPSY 1-2-3) to simplify and standardize the protocol for capturing a biopsy site photograph using the patient's own smartphone. The steps are also intended to improve the resolution and value of the image. A case example is provided. Using the steps of BIOPSY 1-2-3, the case example biopsy site image is clearly identified compared to a less structured image. Using BIOPSY 1-2-3, biopsy site images taken by patient-owned smartphone cameras can empower and involve patients in their care, improve image quality, and reduce medical errors.

Wound Area Measurement with Digital Planimetry: Improved Accuracy and Precision with Calibration Based on 2 Rulers

Introduction

In the treatment of chronic wounds the wound surface area change over time is useful parameter in assessment of the applied therapy plan. The more precise the method of wound area measurement the earlier may be identified and changed inappropriate treatment plan. Digital planimetry may be used in wound area measurement and therapy assessment when it is properly used, but the common problem is the camera lens orientation during the taking of a picture. The camera lens axis should be perpendicular to the wound plane, and if it is not, the measured area differ from the true area.

Results

Current study shows that the use of 2 rulers placed in parallel below and above the wound for the calibration increases on average 3.8 times the precision of area measurement in comparison to the measurement with one ruler used for calibration. The proposed procedure of calibration increases also 4 times accuracy of area measurement. It was also showed that wound area range and camera type do not influence the precision of area measurement with digital planimetry based on two ruler calibration, however the measurements based on smartphone camera were significantly less accurate than these based on D-SLR or compact cameras. Area measurement on flat surface was more precise with the digital planimetry with 2 rulers than performed with the Visitrak device, the Silhouette Mobile device or the AreaMe software-based method.

Conclusion

The calibration in digital planimetry with using 2 rulers remarkably increases precision and accuracy of measurement and therefore should be recommended instead of calibration based on single ruler.

Methods to assess area and volume of wounds - a systematic review

Wound measurement is important in monitoring the healing process of chronic wounds and in evaluating the effect of treatment. The objective of this systematic review was to evaluate evidence from the literature on accuracy, agreement, reliability and feasibility of wound measurement techniques described since 1994. Studies were identified by searching the electronic databases PubMed, Embase and Cochrane Library. Of the 12 013 studies identified, 43 were included in the review. A total of 30 papers evaluated techniques for measuring wound area and 13 evaluated techniques for measuring wound volume. The six approaches for measuring wound area were simple ruler method (10 papers), mathematical models (5 papers), manual planimetry (10 papers), digital planimetry (16 papers), stereophotogrammetry (2 papers) and digital imaging method (20 papers). Of these studies, 10 evaluated accuracy, 15 agreement, 17 reliability and 25 mentioned feasibility. The number of wounds examined in the studies was highly variable (n = 3-260). Studies evaluating techniques for measuring wound volume included between 1 and 50 wounds and evaluated accuracy (4 studies), agreement (6 studies), reliability (8 studies) and feasibility (12 studies). Digital planimetry and digital imaging were considered the most accurate and reliable methods for area measurement, particularly in larger and irregularly shaped wounds. None of the three-dimensional technologies have so far had a major impact, because of their low accuracy, high cost and complexity in handling the system set-up.