An overview of techniques used to measure wound area and volume

Application of a Diabetic Foot Smart APP in the measurement of diabetic foot ulcers

AIMS

In the early stage, we developed an intelligent measurement APP for diabetic foot ulcers, named Diabetic Foot Smart APP. This study aimed to validate the APP in the measurement of ulcer area for diabetic foot ulcer (DFU).

METHODS

We selected 150 DFU images to measure the ulcer areas using three assessment tools: the Smart APP software package, the ruler method, and the gold standard Image J software, and compared the measurement results and measurement time of the three tools. The intra-rater and inter-rater reliability were described by Pearson correlation coefficient, intra-group correlation coefficient, and coefficient of variation.

RESULTS

The Image J software showed a median ulcer area of 4.02 cm2, with a mean measurement time of 66.37 ± 7.95 s. The ruler method showed a median ulcer area of 5.14 cm2, with a mean measurement time of 171.47 ± 46.43 s. The APP software showed a median ulcer area of 3.70 cm2, with a mean measurement time of 38.25 ± 6.81 s. There were significant differences between the ruler method and the golden standard Image J software (Z = -4.123, p < 0.05), but no significant difference between the APP software and the Image J software (Z = 1.103, p > 0.05). The APP software also showed good inter-rater reliability and intra-rater reliability, with both reaching 0.99.

CONCLUSION

The Diabetic Foot Smart APP is a fast and reliable measurement tool with high measurement accuracy that can be easily used in clinical practice for the measurement of ulcer areas of DFU.

TRIAL REGISTRATION

Chinese clinical trial registration number: ChiCTR2100047210.

Convolution Neural Network with Coordinate Attention for Real-Time Wound Segmentation and Automatic Wound Assessment

BACKGROUND

Wound treatment in emergency care requires the rapid assessment of wound size by medical staff. Limited medical resources and the empirical assessment of wounds can delay the treatment of patients, and manual contact measurement methods are often inaccurate and susceptible to wound infection. This study aimed to prepare an Automatic Wound Segmentation Assessment (AWSA) framework for real-time wound segmentation and automatic wound region estimation.

METHODS

This method comprised a short-term dense concatenate classification network (STDC-Net) as the backbone, realizing a segmentation accuracy-prediction speed trade-off. A coordinated attention mechanism was introduced to further improve the network segmentation performance. A functional relationship model between prior graphics pixels and shooting heights was constructed to achieve wound area measurement. Finally, extensive experiments on two types of wound datasets were conducted.

RESULTS

The experimental results showed that real-time AWSA outperformed state-of-the-art methods such as mAP, mIoU, recall, and dice score. The AUC value, which reflected the comprehensive segmentation ability, also reached the highest level of about 99.5%. The FPS values of our proposed segmentation method in the two datasets were 100.08 and 102.11, respectively, which were about 42% higher than those of the second-ranked method, reflecting better real-time performance. Moreover, real-time AWSA could automatically estimate the wound area in square centimeters with a relative error of only about 3.1%.

CONCLUSION

The real-time AWSA method used the STDC-Net classification network as its backbone and improved the network processing speed while accurately segmenting the wound, realizing a segmentation accuracy-prediction speed trade-off.

Therapeutic Effect and Mechanism of Negative Pressure Wound Therapy with Huoxue Shengji Decoction Instillation for Chronic Skin Ulcers

Background

Negative pressure wound therapy (NPWT) with instillation (NPWTi) is a new treatment for chronic skin ulcers (CSUs), but the choice of perfusate is still investigated. The clinical application of Huoxue Shengji (HXSJ) decoction has been proved to promote the formation of granulation. The formation of fresh granulation, angiogenesis, and proliferation of vascular endothelial cells are closely related. The purpose of this study was to observe the clinical efficacy of NWPT with HXSJ decoction instillation in the treatment of CSUs and to explore the potential mechanism by which HXSJ decoction promotes proliferation of vascular endothelial cells at the cellular level.

Methods

In the clinical study, the random number table was used to divide the patients into three groups (patients were numbered by visit time and assigned a random number and grouped by the remainder after the random number was divided by 3, and when the number of patients in one group reached 20, the enrolment of this group is stopped), including NPWT combined with HXSJ decoction instillation (group A), NPWT combined with normal saline instillation (group B), and NPWT (group C). Related indexes were examined, including the wound cavity volume, bacterial culture, histopathology examination, time periods of debridement, repair methods, and the time of ulcer healing. In the basic research, the effect of HXSJ decoction on the proliferation of HUVECs was analysed by CCK-8 assay and RT-PCR and western blot were used to quantify the VEGF and VEGFR-2 expression in the relevant signalling pathway.

Results

There was no significant difference in the improvement rate of invasive cavity volume (P > 0.05) between groups A and B, but a significant difference was observed between groups A and C (P < 0.05). There was no significant difference in microbial reduction among groups (all P > 0.05). Histopathological examination showed that the microvascular count in group A was significantly higher than that in groups B and C (both P < 0.01) and there was no statistical difference between groups B and C (P > 0.05). There were no significant differences in the number of invasive lesions and repair methods among the groups (all P > 0.05). The healing time of group A was significantly faster than those of groups B and C (compared to group B, P < 0.05; compared to group C, P < 0.01), and there was no statistical difference between groups B and C (P > 0.05). In the cellular experiments, concentration screening was performed and 125 μg/mL HXSJ decoction showed the most significant effect on the proliferation of HUVECs and also enhanced the expression of VEGF and VEGFR-2.

Conclusion

HXSJ decoction can enhance the expression of VEGF and VEGFR-2 and promote the proliferation of HUVECs. Treatment with NWPT with HXSJ decoction instillation can further reduce the wound cavity volume; meanwhile, it can promote blood vessel formation in ulcer wounds, thus accelerating the healing of CSUs.

The state of wound assessment tools in Singapore: an evaluation study

OBJECTIVE

Variations in wound assessment and documentation remain an issue for clinicians despite efforts to standardise practices using national guidelines such as the Wound Care Assessment Minimum Data Set (WCA-MDS). As little is known about the quality of the wound assessment tools (WATs) used in Singapore, this study aimed to determine whether the existing WATs used meet the WCA-MDS criteria and clinicians' needs.

METHOD

The study adopted an action evaluation methodology to evaluate seven well-established WATs, such as the Applied Wound Management (AWM) and National Wound Assessment Form (NWAF), and eight locally-designed WATs against the 34-item WCA-MDS criteria. Two clinicians reviewed the WATs using a self-developed audit form between June and July 2020.

RESULTS

The results show that only five WATs met at least 50% of the 34 criteria indicators, with the MEASURE assessment framework achieving the most at 68%, followed by TIME-CDST at 65%, Hospital C WAT at 56%, NWAF at 53%, and AWM form at 50%. The five most common criteria indicators included wound type/classification, date and time of wound, wound size, wound bed tissue type, and exudate information. Most criteria indicators under the 'patient information' and 'specialist's referral' subdomains were omitted, reflecting the lack of focus on these areas in the local WATs.

CONCLUSION

Despite advances in WAT development in the literature, the current state of wound assessment and documentation across healthcare institutions remains inconsistent. There is a need to focus on clinician training and establishing a nationally-validated WAT in Singapore.

The UTrack framework for segmenting and measuring dermatological ulcers through telemedicine

Chronic dermatological ulcers cause great discomfort to patients, and while monitoring the size of wounds over time provides significant clues about the healing evolution and the clinical condition of patients, the lack of practical applications in existing studies impairs users' access to appropriate treatment and diagnosis methods. We propose the UTrack framework to help with the acquisition of photos, the segmentation and measurement of wounds, the storage of photos and symptoms, and the visualization of the evolution of ulcer healing. UTrack-App is a mobile app for the framework, which processes images taken by standard mobile device cameras without specialized equipment and stores all data locally. The user manually delineates the regions of the wound and the measurement object, and the tool uses the proposed UTrack-Seg segmentation method to segment them. UTrack-App also allows users to manually input a unit of measurement (centimeter or inch) in the image to improve the wound area estimation. Experiments show that UTrack-Seg outperforms its state-of-the-art competitors in ulcer segmentation tasks, improving F-Measure by up to 82.5% when compared to superpixel-based approaches and up to 19% when compared to Deep Learning ones. The method is unsupervised, and it semi-automatically segments real-world images with 0.9 of F-Measure, on average. The automatic measurement outperformed the manual process in three out of five different rulers. UTrack-App takes at most 30 s to perform all evaluation steps over high-resolution images, thus being well-suited to analyze ulcers using standard mobile devices.

Clinical Benefits of Using a Smartphone Application to Assess the Wound Healing Process in a Feline Patient - A Case Report

The aim of this paper was to determine whether digital imagery can be employed in veterinary medicine to measure and analyze wound healing dynamics. A smartphone application (ImitoMeasure) was used to capture, measure, and analyze the metatarsal wound images in a cat patient. The smartphone app was used to evaluate the wound area, width, length, and circumference at the time of topical treatments. Further analysis of the measurements taken by the ImitoMeasure app revealed significant correlations among all analyzed parameters. The day of treatment was inversely correlated with all the parameters of the wound, showing the healing progress over time. Also, the width was the most influential parameter (P ≤ .05) when assessing wound area. Thus, the app provided a noncontact, easy to use, and accurate smart wound measurement solution. Additionally, this case report describes the treatment of a cat with a severe chronic metatarsal wound and extensive soft tissue loss using a commercially available silver calcium alginate dressing (Askina Calgitrol Ag, B. Braun). The dressing was changed every 2 days, in the first week of treatment, and then every 3 days until the cat was discharged, 21 days later. Granulation tissue formed rapidly, from the fourth day of treatment and continued to expand in the entire wound bed; epithelization process started since the 16th day of treatment and mature scar tissue could be observed 21 days postinjury.

Vivostat Platelet-Rich Fibrin® for Complicated or Chronic Wounds-A Pilot Study

Vivostat Platelet-Rich Fibrin^® (PRF) is an autologous platelet concentrate used for the local treatment of chronic or complicated wounds. Still, its application for this indication is not evidence-based. Therefore, we performed this monocentric retrospective pilot study investigating the clinical outcome of a local treatment of chronic or complicated wounds in 35 patients (23 male, 12 female, mean age 68.7 years) treated with Vivostat PRF^®. This study population is the largest among published studies analyzing the clinical efficacy of Vivostat PRF^® on chronic wounds so far. Using the perpendicular method we divided the wounds into three sizes (<10, 10–30, and >30 cm²). The clinical efficacy of the Vivostat PRF treatment was the primary endpoint and was divided into three groups of increasing degrees of wound improvement: (1) no improvement of the wound (wound area was not reduced > 10% under Vivostat PRF^® treatment), (2) improvement of the wound (reduced area > 10% under Vivostat PRF^® treatment) and (3) complete epithelialization (wounds that were completely re-epithelialized after Vivostat PRF^® treatment). We included patients’ diagnosis and concomitant diseases (peripheral arterial occlusive disease (PAOD)), chronic venous insufficiency (CVI)), diabetic foot syndrome (DFS)) in our data analysis in order to investigate their potential impact on the wound healing capacity of Vivostat PRF^®. Our results show that in the entire study population, 13 out of 35 (37.1%) patients experienced wound improvement and 14 out of 35 (40%) patients showed complete epithelialization of their wound under Vivostat PRF^® treatment. In summary, 77.1% of the treated patients benefited from the Vivostat PRF^® therapy. These positive wound healing effects were all observed within the first three to six Vivostat PRF^® applications. Subgroup analyses showed that Vivostat PRF^® appeared to be more efficient in patients without CVI in comparison to patients with CVI (p = 0.02). Moreover, Vivostat PRF^® treatment seems to be particularly efficient in PAOD-related wounds with a reduced crural arterial blood supply (p = 0.01). Additionally, we performed an experimental human in vivo study on ten male students where we artificially generated bilateral gluteal wounds and analyzed the influence of the Vivostat PRF^® treatment on the expression of two genes (human beta Defensin-2, ((hBD-2) and human beta-Defensin-3 (hBD-3)) in keratinocytes of resected wound specimens that are induced during wound healing. Interestingly, this analysis revealed that only seven of out ten individuals showed a relevant hBD-2 and hBD-3 gene induction after Vivostat PRF^® treatment. This led to the novel “key-lock-hypothesis”. With the goal of an individualized precision medicine approach with optimized wound treatment strategies in the future, this is an important observation that demands further experimental and clinical studies.

Segmenting skin ulcers and measuring the wound area using deep convolutional networks

BACKGROUND AND OBJECTIVES

Bedridden patients presenting chronic skin ulcers often need to be examined at home. Healthcare professionals follow the evolution of the patients' condition by regularly taking pictures of the wounds, as different aspects of the wound can indicate the healing stages of the ulcer, including depth, location, and size. The manual measurement of the wounds' size is often inaccurate, time-consuming, and can also cause discomfort to the patient. In this work, we propose the Automatic Skin Ulcer Region Assessment ASURA framework to accurately segment the wound and automatically measure its size.

METHODS

ASURA uses an encoder/decoder deep neural network to perform the segmentation, which detects the measurement ruler/tape present in the image and estimates its pixel density.

RESULTS

Experimental results show that ASURA outperforms the state-of-the-art methods by up to 16% regarding the Dice score, being able to correctly segment the wound with a Dice score higher than 90%. ASURA automatically estimates the pixel density of the images with a relative error of 5%. When using a semi-automatic approach, ASURA was able to estimate the area of the wound in square centimeters with a relative error of 14%.

CONCLUSIONS

The results show that ASURA is well-suited for the problem of segmenting and automatically measuring skin ulcers.

Does localized iron loss in venous disease lead to systemic iron deficiency? A descriptive pilot study

Haemosiderin deposition in the legs of patients with venous leg ulcers is well established, and several theories suggest this stored iron has a role in disease pathophysiology. In this novel pilot study of patients with chronic venous leg ulcers, we aimed to establish the relationship between wound fluid iron levels, serum iron parameters and healing. Fifteen patients with venous ulcers were included in the study. Blood samples were taken for full blood count and iron studies, while simultaneously wound fluid was obtained from the wound surface using filter paper. Wound areas were measured at initial and 4 week (+/- 2 day) follow-up visits. We found a positive correlation between wound fluid and serum iron (correlation co-efficient 0.27) and those with the lowest wound fluid iron level were also anemic. No association was found between initial wound area and wound fluid iron level but the largest wound areas were found in patients with anemia. Only 38% of patients demonstrated a reduction in wound area during the 4 week study, and 80% of those were not anemic or iron deficient. Conversely in those patients whose wounds did not reduce in size 88% were anemic or iron deficient. These findings demonstrate a previously unrecognized phenomenon of systemic iron store depletion secondary to leaching out of the body in wound exudate. In addition, these results suggest a high prevalence of anemia in patients with chronic venous ulcers, though whether this is cause or effect requires further research. Our findings also suggest that patients with venous ulcers have a high prevalence of iron deficiency and anemia, which appears to be often undiagnosed, and that diagnostic criteria for iron deficiency in patients with chronic wounds need to be revised to reflect the effect of chronic inflammation on iron metabolism.

Evaluation of the assessment and documentation of chronic wounds in residential social care in the Czech Republic

OBJECTIVE

Accurate evaluation of non-healing, chronic wounds followed by the selection of an appropriate therapeutic strategy is a must for the foundation of health-care management. Assessment of non-healing chronic wounds in clinical practice in the Czech Republic is not standardised in acute care settings or in residential social care facilities. The aim of the study was to analyse the methods being used to assess non-healing, chronic wounds in residential social services in the Czech Republic, where more patients with chronic wounds are present because of the increasing incidence of wounds in old age.

METHOD

The research was carried out at 66 residential social care institutions across all regions of the Czech Republic. A mixed model was used for the research (participatory observation including creation of field notes and content analysis of documents for documentation and analysis of qualitative and quantitative data). The same methodology was used in previous work which has been done in acute care settings in 2013.

RESULTS

The results of this research have corroborated the inconsistencies in procedures used by general nurses for assessment of non-healing, chronic wounds. However, the situation was found to be more positive with regard to the evaluation of basic/fundamental parameters of a wound (e.g. size, depth and location of the wound) compared with the evaluation of more specific parameters (e.g. exudate or signs of infection). This included not only the number of observed variables, but also the action taken. Both were improved when a consultant for wound healing was present.

CONCLUSION

An effective strategy for wound management depends on the method and scope of the assessment of non-healing, chronic wounds in place in clinical practice in observed facilities; improvement may be expected following the general introduction of 'non-healing, chronic wound assessment' algorithm.

Validation of a laser-assisted wound measurement device in a wound healing model

In the treatment and monitoring of a diabetic or chronic wound, accurate and repeatable measurement of the wound provides indispensable data for the patient's medical record. This study aims to measure the accuracy of the laser-assisted wound measurement (LAWM) device against traditional methods in the measurement of area, depth and volume. We measured four 'healing' wounds in a Play-Doh(®) -based model over five subsequent states of wound healing progression in which the model was irregularly filled in to replicate the healing process. We evaluated the LAWM device against traditional methods including digital photograph assessment with National Institutes of Health ImageJ software, measurements of depth with a ruler and weight-to-volume assessment with dental paste. Statistical analyses included analysis of variance (ANOVA) and paired t-tests. We demonstrate that there are significantly different and nearly statistically significant differences between traditional ruler depth measurement and LAWM device measurement, but there are no statistically significant differences in area measurement. Volume measurements were found to be significantly different in two of the wounds. Rate of percentage change was analysed for volume and depth in the wound healing model, and the LAWM device was not significantly different than the traditional measurement technique. While occasionally inaccurate in its absolute measurement, the LAWM device is a useful tool in the clinician's arsenal as it reliably measures rate of percentage change in depth and volume and offers a potentially aseptic alternative to traditional measurement techniques.

A Simple Mathematical Model for Wound Closure Evaluation

The incidence of ulcers associated to type 2 diabetes mellitus (T2DM) increases every year. We introduce and explore a new mathematical algorithm to evaluate wound-healing in foot ulcers associated to T2DM. Fifteen patients (nine women and six men), mean age of 70 ± 16 years were included. The evolution of their wounds followed-up for a period of 18-45 days. According to the Wagner grading system the ulcers were grade I (5 patients), grade II (9 patients), and grade III (1 patient). Clinically, the type of the ulcers was neuroischemic (12 patients) and neuropathic (3 patients). A new parameter is introduced, the "continuous linear healing rate" Dc that was more accurate with higher values and requires less quantifications than usual formulas to make a wound-healing projection.

Pilot study to evaluate a novel three-dimensional wound measurement device

As the burden of diabetes continues to grow and treatment standards require careful tracking of wound progress, clinicians increasingly need to rely on technological improvements in wound measurement technologies to track the progress of their treatments. This study aims to determine the accuracy of a new three-dimensional wound measurement (3DWM) device against laser-assisted wound measurement (LAWM) devices and traditional methods of wound measurement. Using several wound models, we demonstrate that the 3DWM device measures wound area, depth and volume similarly to the other methods tested. This is especially apparent when changes in wound measurements were compared between the two devices. Differences between the two technologies were apparent when analysing wound measurement time and measurement repeatability. There was a significantly lower incidence of error in measurements between the 3DWM device and the LAWM device. Finally, the measurement time was significantly faster with the 3DWM device compared to the LAWM device. Together, these data demonstrate that the 3DWM device provides an accurate and reproducible method for measuring changes in wound healing similar to other available technologies. Further, the use of the 3DWM device provides a faster and more consistent measurement, which is critical for clinical application and use.

Wound assessment tools and nurses' needs: an evaluation study

The purpose of this study was to ascertain how well different wound assessment tools meet the needs of nurses in carrying out general wound assessment and whether current tools are fit for purpose. The methodology employed was evaluation research. In order to conduct the evaluation, a literature review was undertaken to identify the criteria of an optimal wound assessment tool which would meet nurses' needs. Several freely available wound assessment tools were selected based on predetermined inclusion and exclusion criteria and an audit tool was developed to evaluate the selected tools based on how well they met the criteria of the optimal wound assessment tool. The results provide a measure of how well the selected wound assessment tools meet the criteria of the optimal wound assessment tool. No tool was identified which fulfilled all the criteria, but two (the Applied Wound Management tool and the National Wound Assessment Form) met the most criteria of the optimal tool and were therefore considered to best meet nurses' needs in wound assessment. The study provides a mechanism for the appraisal of wound assessment tools using a set of optimal criteria which could aid practitioners in their search for the best wound assessment tool.

Wound perimeter, area, and volume measurement based on laser 3D and color acquisition

Background

Wound measuring serves medical personnel as a tool to assess the effectiveness of a therapy and predict its outcome. Clinically used methods vary from measuring using rules and calipers to sophisticated methods, based on 3D measuring. Our method combines the added value of 3D measuring and well-known segmentation algorithms to enable volume calculation and achieve reliable and operator-independent analysis, as we demonstrate in the paper.

Methods

Developed 3D measuring system is based on laser triangulation with simultaneous color acquisition. Wound shape analysis is based on the edge-determination, virtual healthy skin approximation over the wound and perimeter, area, and volume calculation. In order to validate the approach, eight operators analyzed four different wounds using proposed method. Measuring bias was assessed by comparing measured values with expected values on an artificially modeled set of wounds.

Results

Results indicate that the perimeter, area, and volume are measured with a repeatability of 2.5 mm, 12 mm², and 30 mm³, respectively, and with a measuring bias of −0.2 mm, −8.6 mm², 24 mm³, respectively.

Conclusions

According to the results of verification and the fact that typical wound analysis takes 20 seconds, the method for wound shape measurement can be clinically used as a precise tool for objectively monitoring the wound healing based on measuring its 3D shape and color.

Assessment and documentation of non-healing, chronic wounds in inpatient health care facilities in the Czech Republic: an evaluation study

The foundation of health care management of patients with non-healing, chronic wounds needs accurate evaluation followed by the selection of an appropriate therapeutic strategy. Assessment of non-healing, chronic wounds in clinical practice in the Czech Republic is not standardised. The aim of this study was to analyse the methods being used to assess non-healing, chronic wounds in inpatient facilities in the Czech Republic. The research was carried out at 77 inpatient medical facilities (8 university/faculty hospitals, 63 hospitals and 6 long- term hospitals) across all regions of the Czech Republic. A mixed model was used for the research (participatory observation including creation of field notes and content analysis of documents for documentation and analysis of qualitative and quantitative data). The results of this research have corroborated the suspicion of inconsistencies in procedures used by general nurses for assessment of non-healing, chronic wounds. However, the situation was found to be more positive with regard to evaluation of basic/fundamental parameters of a wound (e.g. size, depth and location of a wound) compared with the evaluation of more specific parameters (e.g. exudate or signs of infection). This included not only the number of observed variables, but also the action taken. Both were significantly improved when a consultant for wound healing was present (P = 0·047). The same applied to facilities possessing a certificate of quality issued by the Czech Wound Management Association (P = 0·010). In conclusion, an effective strategy for wound management depends on the method and scope of the assessment of non-healing, chronic wounds in place in clinical practice in observed facilities; improvement may be expected following the general introduction of a 'non-healing, chronic wound assessment' algorithm.

High-resolution harmonics ultrasound imaging for non-invasive characterization of wound healing in a pre-clinical swine model

This work represents the first study employing non-invasive high-resolution harmonic ultrasound imaging to longitudinally characterize skin wound healing. Burn wounds (day 0-42), on the dorsum of a domestic Yorkshire white pig were studied non-invasively using tandem digital planimetry, laser speckle imaging and dual mode (B and Doppler) ultrasound imaging. Wound depth, as measured by B-mode imaging, progressively increased until day 21 and decreased thereafter. Initially, blood flow at the wound edge increased up to day 14 and subsequently regressed to baseline levels by day 21, when the wound was more than 90% closed. Coinciding with regression of blood flow at the wound edge, there was an increase in blood flow in the wound bed. This was observed to regress by day 42. Such changes in wound angiogenesis were corroborated histologically. Gated Doppler imaging quantitated the pulse pressure of the primary feeder artery supplying the wound site. This pulse pressure markedly increased with a bimodal pattern following wounding connecting it to the induction of wound angiogenesis. Finally, ultrasound elastography measured tissue stiffness and visualized growth of new tissue over time. These studies have elegantly captured the physiological sequence of events during the process of wound healing, much of which is anticipated based on certain dynamics in play, to provide the framework for future studies on molecular mechanisms driving these processes. We conclude that the tandem use of non-invasive imaging technologies has the power to provide unprecedented insight into the dynamics of the healing skin tissue.

Wound samples: moving towards a standardised method of collection and analysis

Chronic wounds, including diabetic foot ulcers, pressure ulcers and venous leg ulcers, impact the lives of millions of people worldwide. These types of wounds represent a significant physical, social and financial burden to both patients and health care systems. Wound care has made great progress in recent years as a result of the critical research performed in academic, clinical and industrial settings. However, there has been relatively little translation of basic research discoveries into novel and effective treatments. One underlying reason for this paucity may be inconsistency in the methods of wound analysis and sample collection, resulting in the inability of researchers to accurately characterise the healing process and compare results from different studies. This review examines the various types of analytical methods being used in wound research today with emphasis on sampling techniques, processing and storage, and the findings call forth the wound care research community to standardise its approach to wound analysis in order to yield more robust and comparable data sets.

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.

Validation of a laser-assisted wound measurement device for measuring wound volume

BACKGROUND

Accurate and precise wound measurement is an essential part of the medical record when monitoring a patient with a chronic wound. This study was designed to determine if a new device, a laser-assisted wound measurement (LAWM) device, provides valid measurements for wound area, depth, and volume.

METHODS

We compared four methods to evaluate the area and volume of 12 wounds of differing size and depth that were created on the dorsum of a sacrificed pig. We evaluated the LAWM device, digital photograph assessment with National Institutes of Health ImageJ software, measurements of depth with a ruler, and weight-to-volume assessment with dental paste. We then sought to cross validate this data with further analyses obtained from these measurements using a Play-Doh®-based wound as a model for constant area with different depths.

RESULTS

We demonstrate that the LAWM device measures wound area accurately. Depth (and therefore volume) measurements, however, are artificially low. This inaccuracy is the same for shallow and deep wounds.

CONCLUSIONS

The inaccuracy in the depth and volume measurements with the LAWM device results in an artificially low measurement. However, this may not affect percentage difference measurements. Further studies will need to be performed to determine if this device can accurately determine wound changes in the clinical setting.

Repeatability and clinical utility in stereophotogrammetric measurements of wounds

OBJECTIVE

To investigate the hypothesis that stereophotogrammetric wound size monitoring shows suitable inter-observer reliability and user acceptance for clinical practice use.

METHOD

Veterans admitted for conservative management of severe pressure ulcers were eligible for inclusion in the study. Three-dimensional (3D) digital wound images were independently captured by two expert and two non-expert nurse-observers using a commercially available stereophotogrammetry system,weekly for 6 weeks.A double-blinded analyst generated 3D wound reconstructions, using software to determine geometry. Clinical opinion of wound progression was provided by an expert physician.

RESULTS

Thirteen wounds were assessed with more than 80% of all images being readable. Interclass correlation of 0.9867 (p < 0.000 I) was observed. Compared with clinical opinion, 3D wound measurement was sensitive between improving and static wounds for wound perimeter, volume, depth and length.

CONCLUSION

These preliminary findings suggest that 3D wound measurement minimises differences in wound measurement between expert and non-expert observers, suggesting it could be implemented with high reliability in health-care settings where several observers are involved in wound care management.

A systematic review of the performance of instruments designed to measure the dimensions of pressure ulcers

The objective was to undertake a systematic review of the performance of wound measurement instruments used for patients with pressure ulcers. Studies of any design, evaluating methods for estimating wound diameter, depth, surface area, or volume in patients with pressure ulcers were included. Eligible evaluations had to report intra- or inter-rater reliability, accuracy, agreement, or feasibility of methods. Electronic databases and other sources were accessed for study identification. Included studies were critically appraised using a modified checklist for diagnostic test evaluations. Twelve studies were included. Most had methodological problems and/or used inappropriate statistical methods. Reliable methods for measuring pressure ulcer surface area may include: grid tracings from photographs combined with whole plus partial square count; a portable digital pad; and stereophotogrammetry combined with computerized image analysis. The agreement between photographic tracing and direct transparency tracing may be satisfactory (both methods being combined with computerized planimetry). No definitive conclusions could be reached about studies of diameter or depth; this means that there is little evidence to underpin recommendations in clinical guidelines. Evaluations of volume measurement were of poor quality, and there were few data on feasibility. Further primary research is needed to evaluate methods of wound measurement used in clinical practice.

Bioelectrical impedance assessment of wound healing

Objective assessment of wound healing is fundamental to evaluate therapeutic and nutritional interventions and to identify complications. Despite availability of many techniques to monitor wounds, there is a need for a safe, practical, accurate, and effective method. A new method is localized bioelectrical impedance analysis (BIA) that noninvasively provides information describing cellular changes that occur during healing and signal complications to wound healing. This article describes the theory and application of localized BIA and provides examples of its use among patients with lower leg wounds. This promising method may afford clinicians a novel technique for routine monitoring of interventions and surveillance of wounds.