Comparative analysis of two methods for wound bed area measurement

A time motion study of manual versus artificial intelligence methods for wound assessment

Objectives

This time-motion study explored the amount of time clinicians spent on wound assessments in a real-world environment using wound assessment digital application utilizing Artificial Intelligence (AI) vs. manual methods. The study also aimed at comparing the proportion of captured quality wound images on the first attempt by the assessment method.

Methods

Clinicians practicing at Valley Wound Center who agreed to join the study were asked to record the time needed to complete wound assessment activities for patients with active wounds referred for a routine evaluation on the follow-up days at the clinic. Assessment activities included: labelling wounds, capturing images, measuring wounds, calculating surface areas, and transferring data into the patient’s record.

Results

A total of 91 patients with 115 wounds were assessed. The average time to capture and access wound image with the AI digital tool was significantly faster than a standard digital camera with an average of 62 seconds (P<0.001). The digital application was significantly faster by 77% at accurately measuring and calculating the wound surface area with an average of 45.05 seconds (P<0.001). Overall, the average time to complete a wound assessment using Swift was significantly faster by 79%. Using the AI application, the staff completed all steps in about half of the time (54%) normally spent on manual wound evaluation activities. Moreover, acquiring acceptable wound image was significantly more likely to be achieved the first time using the digital tool than the manual methods (92.2% vs. 75.7%, P<0.004).

Conclusions

Using the digital assessment tool saved significant time for clinicians in assessing wounds. It also successfully captured quality wound images at the first attempt.

Evaluation of three different techniques for measuring wound area in diabetic foot ulcers: a reproducibility study

OBJECTIVE

Wound surface area can be measured with several assessment tools, including a manual planimetric method, ImageJ software and three-dimensional wound measurement (3DWM) methods. This study aimed to determine the advantages of each method as well as the concordance between them.

METHOD

This reproducibility study included adult patient volunteers with diabetic foot ulcers (DFUs). Wounds with ambiguous borders were excluded. All included wounds were sequentially assessed with each of the three measurement methods, and the time for each measurement was recorded with a chronometer. SPSS and MedCalc package software were used for all statistical analyses.

RESULTS

A total of 20 patients with 20 DFUs took part in the study. According to the measurement method, the average wound area was 6.41cm² by the manual planimetric method, 6.53cm² by ImageJ and 6.32cm² by 3DWM. Correlation analyses revealed correlation coefficients of 0.997 between the manual planimetric method and ImageJ, 0.929 between the manual planimetric method and 3DWM, and 0.929 between ImageJ and 3DWM. Bland-Altman analysis was used to determine whether these three measurement methods could be used interchangeably. There was no significant difference between the three measurement methods and, therefore, it was concluded that they could be used interchangeably. Wound area measurement times were 173.35±19.38 seconds by the manual planimetric method, 61.60±9.21 seconds by ImageJ and 36.90±6.91 seconds by the 3DWM method.

CONCLUSION

The three measurement methods studied can be used interchangeably, as each method is highly concordant with the other two. The fastest method was 3DWM and the manual planimetric method was the slowest.

Hyperspectral imaging in wound care: A systematic review

Multispectral and hyperspectral imaging (HSI) are emerging imaging techniques with the potential to transform the way patients with wounds are cared for, but it is not clear whether current systems are capable of delivering real-time tissue characterisation and treatment guidance. We conducted a systematic review of HSI systems that have been assessed in patients, published over the past 32 years. We analysed 140 studies, including 10 different HSI systems. Current in vivo HSI systems generate a tissue oxygenation map. Tissue oxygenation measurements may help to predict those patients at risk of wound formation or delayed healing. No safety concerns were reported in any studies. A small number of studies have demonstrated the capabilities of in vivo label-free HSI, but further work is needed to fully integrate it into the current clinical workflow for different wound aetiologies. As an emerging imaging modality for medical applications, HSI offers great potential for non-invasive disease diagnosis and guidance when treating patients with both acute and chronic wounds.

Hyperspectral imaging in wound care: A systematic review

Multispectral and hyperspectral imaging (HSI) are emerging imaging techniques with the potential to transform the way patients with wounds are cared for, but it is not clear whether current systems are capable of delivering real-time tissue characterisation and treatment guidance. We conducted a systematic review of HSI systems that have been assessed in patients, published over the past 32 years. We analysed 140 studies, including 10 different HSI systems. Current in vivo HSI systems generate a tissue oxygenation map. Tissue oxygenation measurements may help to predict those patients at risk of wound formation or delayed healing. No safety concerns were reported in any studies. A small number of studies have demonstrated the capabilities of in vivo label-free HSI, but further work is needed to fully integrate it into the current clinical workflow for different wound aetiologies. As an emerging imaging modality for medical applications, HSI offers great potential for non-invasive disease diagnosis and guidance when treating patients with both acute and chronic wounds.

Using AutoCAD software to measure venous leg ulcers: a reproducibility assessment study

OBJECTIVE

To assess the reproducibility of using AutoCAD software to measure the area of venous leg ulcers (VLUs).

METHOD

Data from patients with VLUs were collected between March and July 2015, using data collection forms and photographing the different ulcers. A researcher and five nurses collected the data. The wounds were measured using AutoCAD software. Data were analysed using intraclass correlation coefficient (ICC), concordance correlation coefficient (CCC) and Bland-Altman analysis.

RESULTS

A total of 21 patients with 36 VLUs were included in the study. A statistically significant difference (p<0.05) was observed between the areas of VLUs measured by the researcher and the evaluators. There was an excellent agreement when analysing the ICC [p=0.98; 95% CI (0.97-0.99); p <0.05] and the CCC [CCC=CI 0.97; 95% (0.95-0.98)]. There was no difference between the measurements of VLUs ≤10 cm² (p=0.49) and those with an area >10cm² (p=0.22).

CONCLUSION

The use of AutoCAD software is appropriate for measuring VLUs and appears to be more accurate when used to measure VLUs with an area >10cm².

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.

Interrater and intrarater reliability of silhouette wound imaging device

OBJECTIVE

The objective of this study was to investigate the interrater and intrarater reliability of a wound imaging and measurement system called SilhouetteMobile.

DESIGN

Interrater and intrarater reliability study.

SETTING

Community nursing, Victoria, Australia.

PARTICIPANTS

Seven community nurses including Wound Management Clinical Nurse Consultants and Wound Resource Nurses.

MAIN OUTCOME MEASURE

Average wound surface area of 14 wound images as captured using a wound imaging and measurement system called SilhouetteMobile.

MAIN RESULTS

High interrater and intrarater reliability were maintained across different users and different assessments by the same user and were also found to be unaffected by image quality. Reliability was poor when tracing small wounds.

CONCLUSION

Silhouette is a highly reliable tool for wound imaging and measurement, although reliability is reduced when annotating small wound areas.

Concurrent validation and reliability of digital image analysis of granulation tissue color for clinical pressure ulcers

Granulation tissue color is one indicator for pressure ulcer (PU) assessment. However, it entails a subjective evaluation only, and quantitative methods have not been established. We developed color indicators from digital image analysis and investigated their concurrent validity and reliability for clinical PUs. A cross-sectional study was conducted on 47 patients with 55 full-thickness PUs. After color calibration, a wound photograph was converted into three images representing red color: erythema index (EI), modified erythema index with additional color calibration (granulation red index [GRI]), and , which represents the artificially created red-green axis of L(*) a(*) b(*) color space. The mean intensity of the granulation tissue region and the percentage of pixels exceeding the optimal cutoff intensity (% intensity) were calculated. Mean GRI (ρ=0.39, p=0.007) and (ρ=0.55, p<0.001), as well as their % intensity indicators, showed positive correlations with a(*) measured by tristimulus colorimeter, but erythema index did not. They were correlated with hydroxyproline concentration in wound fluid, healthy granulation tissue area, and blood hemoglobin level. Intra- and interrater reliability of the indicator calculation using both GRI and had an intraclass correlation coefficient >0.9. GRI and from digital image analysis can quantitatively evaluate granulation tissue color of clinical PUs.