Burn Depth Assessment Research Articles

Using blood flow pulsatility to improve the accuracy of laser speckle contrast imaging in the assessment of burns.

Measurement of perfusion is an established method to evaluate the depth of burns. However, high accuracy is only achievable >48 h after injury. The aim of the study was to investigate if measurement of blood flow pulsatility, combined with perfusion measurement, can improve early assessment of burn depth using laser speckle contrast imaging (LSCI). Perfusion and pulsatility were measured with LSCI in 187 regions of interest in 32 patients, between 0 and 5 days after injury. The reproducibility of pulsatility was tested for recording durations between 1 and 12 s. The most reproducible duration was chosen, and receiver operator characteristics were created to find suitable pulsatility cut-offs to predict surgical need. A measurement duration of 8 s resulted in a good reproducibility of the pulsatility (%CV: 15.9%). Longer measurement durations resulted in a small improvement of the accuracy of the assessment. A pulsatility of <1.45 (Perfusion Units)2 on day 0-2 after injury predicted surgical need with a sensitivity of 100% (95% CI: 83.2-100%), specificity of 100% (95% CI: 95.2-100%), a positive predictive value of 100%, and a negative predictive value of 100%. Pulsatility was not significantly different when comparing measurements done day 0-2 to day 3-5. Perfusion was however significantly higher day 3-5 compared to day 0-2 for wounds healing within 3 weeks. Measurement of pulsatility improves the accuracy of the assessment of burns with LSCI and makes it possible to predict the need for surgery during day 0-2 after injury with a high accuracy.

731 The Wound Rounds Survey: Measuring Burn Wound Reading Skills

Abstract Introduction The assessment of burn depth and the prediction of spontaneous wound healing potential is one of the most important roles of any provider assessing burn wounds. In an attempt to determine whether burn wound reading by physical exam to determine best clinical treatment is a skill that can be measured, this article describes a method developed and employed at this urban burn center for assessment of burn wounds. Methods This study was conducted from August 8, 2019 to September 19, 2019. Study participants were attending physicians, fellows, residents and physician assistants. Cases were anonymized by the removal of personal identifiers, and participants were sent an SMS via mobile phone of a link to a Google Forms survey. After in person examination of the burn wounds, participants voted on each patient seen. Survey answer choices were 1 (healing without need for surgery), 2 (unsure), and 3 (need for surgical excision). Wound evaluations with unanimous responses were felt not to demonstrate the skill of burn wound assessment, as some wounds were obviously in need of surgery or were going to heal to even the most inexperienced examiner. The participants were grouped into expert, intermediate and novice groups, and the responses were classified as correct or incorrect based on the final outcome of the patient. Mean percentage of correct responses were calculated for each group, and statistical analysis of the means was performed using a one-way weighted ANOVA test. Results During the study period a total of 56 voting events were recorded, 26 of which were excluded based on exclusion criteria. The percentage of correct responses was 58.5 ±8.2% in the expert group (n=94), 50.8 ±11.7% in the intermediate group (n=65), and 41.7 ±16.8% in the novice group (n=72). ANOVA analysis showed that these were statistically significant differences (p &amp;lt; 0.01). Conclusions This pilot study shows that the current survey method of assessing burn wounds resulted in higher scores in experts when compared to intermediate and novice level practitioners, suggesting that burn wound reading is a skill that can be measured. Further development of a formative assessment could aid in the development of an educational module to improve wound reading skills. Applicability of Research to Practice Utilizing a daily survey as an instrument of formative assessment on burn wound reading.

93 Optical Coherence Tomography: A New Imaging Technique for Burn Injuries

Abstract Introduction Accurate assessment of burn depth and healing time remains elusive. As a result, some patients may wait weeks, through painful wound care only to have surgery. Others may have early surgery on wounds that may have healed with a good outcome. Expert opinion remains the most common method of wound evaluation. We sought to evaluate if Optical Coherence Tomography (OCT) with Microangiography (OMAG) can predict burn wound healing. Methods We prospectively enrolled a cohort of 17 burned subjects whose attending physician initially evaluated the depth of the wound as indeterminate. Burn wounds were scanned on enrollment and weekly, until healed or grafted, using a clinical prototype swept source OCT with OMAG capability. Wounds were also assessed by the attending physician for depth of injury and healing time. Wounds were photographed at the time of each scan. OCT and OMAG scans were then used to quantitatively determine blood vessel depth and density within the wound. Univariate regression with clustering and panel effects evaluated the association with healing time. Photographs and scans of each wound from all time points were evaluated by 5 blinded assessors (four surgeons and an OCT engineer) for time to wound healing. Kappa was used to measure the interrater reliability between evaluators. Results The mean patient age was 46 years with a mean burn size of 10% body surface area. Fourteen patients ultimately healed their wounds. Three patients underwent excision and grafting. There was no significant association between vessel depth or density and healing time (Table). Similarly, vessel depth was not predictive of the need for surgery. However, vessel density £ 0.255 perfectly predicted the need for surgery. There was no agreement between evaluators regarding predicted healing looking at OCT and OMAG scans (Kappa 0.003). There was moderate agreement between evaluators predicting healing from photos (Kappa 0.047). Conclusions This preliminary data demonstrates that quantitative OCT/OMAG data shows promise in predicting which patients undergo surgical therapy. Variation of healing estimates from provider image assessment support the best use of this tool as a quantitative measure. Larger studies are needed to explore these findings and the role of this technology. Applicability of Research to Practice OCT/OMAG is a quantitative tool that shows promise in predicting which patients undergo surgical therapy.

116 Short Wave Infrared Light Imaging Distinguishes Superficial from Deep Burns

Abstract Introduction Burns represent a significant public health burden that rely on accurate diagnosis of burn depth. The gold standard for burn injury depth remains visual clinician appraisal. Candidate modalities for objective and standardized diagnostics have failed to reach wide adoption due to limitations in practicality, cost, and reproducibility. Here we utilize short wave infrared spectroscopy (SWIR) which involves analysis of a subset of the infrared spectrum, between 1000–2500 nm, and has previously been described in the assessment of water composition in human skin. Given literature highlighting moisture as a potential biomarker for tissue viability, we hypothesized a similar application in a novel, healthcare context for assessing tissue damage following contact burn injury. Methods A custom imaging system was constructed with tungsten-filament light source, filters centered at 1200, 1650, 1940, and 2250 nm, and a SWIR camera. Phantom models of agar slabs were constructed at 1, 2, 3, 5, and 10 mm thickness and spectrally interrogated in epi-illumination and trans-illumination configurations (Fig A, top). For verification of moisture detection, filter paper was wetted with 50 µL H2O and imaged. For burns study, Yorkshire pigs (N=5) were injured with both short (20 s) and long (40 s) exposure burns to assess varying degrees of burn injury for SWIR and biopsy histology (H&amp;E, picrosirius). In vivo imaging occurred 72 hours after burn injury. For quantifications, a 50x50 pixel region was selected from the center of each burn site to determine average reflectance. Results Absorbance of SWIR light was found to depend on agar thickness, increasing with depth and moisture in substrates. 1940 nm absorbance was sensitive with full absorbance even in agar slabs as thin as 1 mm (Fig A, bottom). Water directly applied to paper demonstrated sharp demarcation of dry vs. wet regions consistent with absorptive patterns seen in agar (Fig B). Short (S) and long (L) regions of porcine burns were imaged (Fig C-D). Two-way ANOVA analysis across 5 animals revealed that reflected fraction was different for each wavelength (p&amp;lt; 0.001) and for both burn exposure times (p=0.011). Imaged wavelengths of 1200, 1650 and 2250, but not 1940 nm, showed a significant 10–20% higher reflectance in the long duration burn in comparison to the short or unburned regions (Fig E). Analysis of biopsies in each treatment region confirmed deeper damage with longer injury times (long: 922±45 vs short: 590±57 mm, n=10/group, p&amp;lt; 0.001, Fig F). Conclusions There exists a need in burn care for a reliable, objective measure of tissue viability following burn injury. SWIR spectroscopy can delineate moisture content in phantom models and distinguish burn depth in porcine models. Applicability of Research to Practice This work to be particularly timely given the need and demand for more objective diagnostic modalities in contemporary burn depth assessment.

734 A Comparison of Burn Depth Assessment Between Clinical Diagnosis and Laser Doppler Imaging

Abstract Introduction Accurate burn assessment is crucial to prescribing appropriate treatment and is dependent upon the experience of the provider and the timing of diagnosis relative to the burn injury evaluation. Differentiating between a deep partial thickness and full thickness burn may not be easily discernible. To augment the clinical diagnosis of burn depth, a laser doppler image measures the microvascular blood flow of injured tissue to predict burn wound healing. The aim of this study is to evaluate the clinical assessment of burn wounds by experienced burn providers compared to the laser doppler image assessment in predicting which burn wounds should heal spontaneously in 3 weeks. Methods A retrospective chart review from 2012–2016, included 54 subjects. The clinical assessment included a description of burn variables relevant to the determination of spontaneous burn wound healing (burn depth, total body surface area, mechanism of injury, anatomical location, clinical burn depth diagnosis, and laser doppler image). A chi-square analysis compared the clinical diagnosis and the laser doppler assessment of burn wound depth, as well as the correlation between clinical diagnosis versus laser doppler image in predicting spontaneous burn wound healing. Results Comparing partial thickness burn injuries, there were 38 clinically diagnosed partial thickness injuries (by experienced burn providers) and 38 partial thickness burn injures diagnosed via LDI. Deep partial thickness burn injuries were diagnosed clinically in 9 subjects, compared to 10 via LDI. Full thickness burn injuries were diagnosed clinically in 7 subjects and 6 via LDI. A chi-square test was performed to examine the relationship between clinical diagnosis of burn depth and laser doppler image. The relation between these variables was significant,X2= 26.884, p&amp;lt; .000. Comparing clinically diagnosed burn depth to LDI, each approach (clinical or LDI) diagnosed 42 subjects with partial thickness or deep partial thickness burn injuries and all healed spontaneously. Two of the clinically diagnosed full thickness burn injuries required skin grafting. Six patients were lost to follow-up (X2= 17.745, p &amp;lt; .001). Conclusions This study confirms there is no difference between an experienced burn provider’s clinical diagnosis of burn wound depth and prognosis for spontaneous healing compared to a laser doppler image prognosis of burn wound healing. Applicability of Research to Practice In an era of advanced technologies, expert clinical bedside assessment is the standard of care.

54 Validation of Infrared Thermography for Prediction of 21-day Burn Wound Healing

Abstract Introduction Although trained specialists easily identify most full and superficial partial thickness burn injuries, deep partial-thickness injuries present a true challenge to the clinician. Various imaging modalities to assess perfusion and determine healing potential include skin biopsy with histology, laser doppler imaging, active dynamic and static infrared thermography, vital dyes, indocyanine green video angiography and others. Prior studies indicate, with small clinical and animal studies, forward looking infrared is a valid tool to assess healing potential and 21-day healing within the first 48 hrs after presentation. The aim of our study is to determine if an absolute increase or decrease in temperature (°C) measurements across a burn wound in a large clinical cohort correlates with 21-day healing after 48 hrs from time of injury. Methods After informed photo consent was obtained, thermographic images were captured at presentation, 24hrs, and 48hrs from patients admitted to our center between October 2018 and August 2019. Thermographic images were reviewed and temp measurements obtained using a linear vector through the wound. Next we determined if patients healed within 21 days. Data collected includes demographic data, burn characteristics, injury site (based on Lund Browder segmentation) and wound temp (average, minimum, maximum). Data was analyzed using Wilcoxon rank sum test with continuity correction. Results We reviewed images for 159 burn sites from 29 patients, the largest image set to be reviewed to date. The cases were 84% male, the mean and range was 33.1 years (1.7 – 70) for age and 25% (2 – 54.5) for TBSA. We found an average temp difference between 24 hrs – 48 hrs (p-value= 0.007) was significant, and no significant difference in average temp change when evaluating admit – 24 hrs (p-value=0.053) and admit – 48 hrs (p-value=0.316), consistent with predictions of prior studies. Average temp from admit – 24 hrs decreased by 0.86°C in healed (n=48) vs non-healed (n=91); increased on average by 1.25°C in healed (n=39) vs non-healed (n=74) from 24 hrs – 48 hrs; and showed a modest decrease by 0.3°C in healed (n=50) vs non-healed (n=82) when comparing admit 48 hr temp. Conclusions These data demonstrate that burn wound temperature difference between 24 and 48 hours after admittance as measured by infrared thermography correlates with clinical outcomes and 21 day healing. Applicability of Research to Practice Infrared thermography is a validated tool to assess burn depth after 48 hrs. In the future, this modality may impact triage in the military, rural, accidental and non-accidental disasters.

Preliminary Assessment of Burn Depth by Paper-Based ELISA for the Detection of Angiogenin in Burn Blister Fluid-A Proof of Concept.

Rapid assessment of burn depth is important for burn wound management. Superficial partial-thickness burn (SPTB) wounds heal without scars, but deep partial-thickness burn (DPTB) wounds require a longer healing time and have a higher risk of scar formation. We previously found that DPTB blister fluid displayed a higher angiogenin level than SPTB blister fluid by conventional ELISA. In this study, we developed a paper-based ELISA (P-ELISA) technique for rapid assessment of angiogenin concentration in burn blister fluid. We collected six samples of SPTB blister fluid, six samples of DPTB blister fluid, and seven normal healthy serum samples for analysis. We again chose ELISA to measure and compare angiogenin levels across all of our samples, but we developed a P-ELISA tool and compared sample results from that tool to the results from conventional ELISA. As with conventional ELISA, DPTB blister fluid displayed higher angiogenin levels than SPTB in P-ELISA. Furthermore, our P-ELISA results showed a moderate correlation with conventional ELISA results. This new diagnostic technique facilitates rapid and convenient assessment of burn depth by evaluating a key molecule in burn blister fluid. It presents a novel and easy-to-learn approach that may be suitable for clinically determining burn depth with diagnostic precision.

A Comparative Study of Segmentation Algorithms in the Classification of Human Skin Burn Depth

A correct first assessment of a skin burn depth is essential as it determines a correct first burn treatment provided to the patients. The objective of this paper is to conduct a comparative study of the different segmentation algorithms for the classification of different burn depths. Eight different hybrid segmentation algorithms were studied on a skin burn dataset comprising skin burn images categorized into three burn classes by medical experts; superficial partial thickness burn (SPTB), deep partial thickness burn (DPTB) and full thickness burn (FTB). Different sequences of the algorithm were experimented as each algorithm was able to segment differently, leading to different segmentation in the final output. The performance of the segmentation algorithms was evaluated by calculating the number of correctly segmented images for each burn depth. The empirical results showed that the segmentation algorithm that was able to segment most of the burn depths had achieved 40.24%, 60.42% and 6.25% of correctly segmented image for SPTB, DPTB and FTB respectively. Most of the segmentation algorithms could not segment well for FTB images because of the different nature of the burn wounds as some of the FTB images contained dark brown and black colors. It can be concluded that a good segmentation algorithm is required to ensure that the representative features of each burn depth can be extracted to contribute to higher accuracy of classification of skin burn depth.

A prospective study comparing the FLIR ONE with laser Doppler imaging in the assessment of burn depth by a tertiary burns unit in the United Kingdom.

Introduction:Laser Doppler imaging (LDI) is the ‘gold standard’ tool for the assessment of burn depth. However, it is costly. The FLIR ONE is a novel, mobile-attached, thermal imaging camera used to assess burn wound temperature. This study compares the FLIR ONE and LDI in assessing burn depth and predicting healing times.Methods:Forty-five adult patients with burn wounds, presenting at 1–5 days, were imaged with the FLIR ONE and LDI. Infected, chemical and electrical burns were excluded. Healing potential was determined by comparing wound and normal skin temperature for the FLIR ONE and blood flow changes with the LDI. Healing potential was categorised into wounds healing in less than and over 21 days. Pearson’s test was used to determine the correlation between changes in wound temperature and healing potential.Results:Percent total body surface area (%TBSA) was in the range of 0.5–45. FLIR demonstrated a sensitivity of 66.67% and specificity of 76.67% in predicting healing within 21 days, while LDI demonstrated a sensitivity of 93.33% and specificity of 40%. The FLIR ONE showed a significant difference in the mean temperature changes between burns that healed in less than (0.1933 ± 0.3554) and over 21 days (–1 ± 0.4329) (P = 0.04904). Pearson’s test showed a significant correlation between the difference in wound and normal skin temperature with healing times (P = 0.04517).Conclusion:The inexpensive FLIR ONE shows a significant correlation between changes in wound temperature and healing times. It is useful in predicting healing within 21 days. However, evaporative cooling at the wound surface can lead to overprediction of healing times and overtreatment.Lay Summary Background Laser Doppler imaging is currently the main tool for burn depth assessment. It works by analysing the blood flow in a burn wound. Based on these findings, it can predict the depth of the burn injury and predict if it will heal in less than or over 21 days. The main problem is that it is costly. The FLIR ONE is a novel, mobile-attached, thermal imaging camera. It can be used to assess burn depth by comparing the temperature of the burn wound to the surrounding normal skin. This information can then be used to predict healing times into less than and over 21 days. The issue being explored The usefulness of the FLIR ONE in assessing burn depth and predicting healing time when compared to the LDI. How was the work conducted? Forty-five adult patients who sustained a burn injury within the last five days were imaged with both the FLIR ONE and LDI. Those with infected, electrical or chemical burns were excluded. Healing potential was determined by comparing the temperature of the burn wound with normal skin for the FLIR ONE and by changes in wound blood flow with the LDI. Healing potential was categorised into wounds healing in less than and over 21 days. The correlation between the temperature changes of the burn wound and healing time was evaluated for the FLIR ONE. What we learned from the study This study was able to demonstrate that the FLIR ONE showed a significant correlation between the temperature difference between the burn wound and normal skin with healing times. When compared with the LDI, the FLIR ONE was useful in predicting if a burn wound will heal in less than 21 days. The FLIR ONE has advantages over the LDI, it is low cost, portable and produces instantaneous images. Ultimately, this developing technology may increase access to higher standard burn care in centres where LDI is not affordable.

Diagnostic Accuracy of Laser Doppler Imaging for the Assessment of Burn Depth: A Meta-analysis and Systematic Review.

An overall assessment of the diagnostic value of laser Doppler imaging (LDI) to assess burn depth in patients is presented based on relevant studies. Both eligible research and relevant articles were identified through specific index searches of Embase, Cochrane, and PubMed databases. The latest study included was published in March 2019 and all eligible publications reported on cohort or cross-sectional research. All articles were tested for heterogeneity by using a suitable effect model to calculate amalgamative values of sensitivity, specificity, and the diagnostic odds ratio (DOR). Analyses of summary receiver operating characteristic (SROC) are given for burn depth values. After rigorous screening, 14 studies with a total cohort of 1,818 patients were chosen for the meta-analysis to explore the validity of LDI diagnosis to assess the depth of burns. The burn depth overall sensitivity for LDI was 91% (95% CI: 86-95%) and global specificity was 96% (95% CI: 92-98%). The overall positive likelihood ratio of LDI was 20.35 (95% CI: 10.71-38.69) and the overall negative likelihood ratio was 0.09 (95% CI: 0.05-0.15). The overall DOR was 152.93 (95% CI: 69.44-336.81) of LDI. The acreage under the SROC was not low for LDI (AUC = 0.98; 95% CI: 0.96-0.99). In conclusion, the present analysis reviewed the literature and meta-analysis of studies to validate LDI for the diagnosis of burn depth. The results indicated that LDI has a high accuracy for this diagnostic function.

Management of the Burn Wound

Current approaches to burn management are based on an understanding of the biology and physiology of human skin and the pathophysiology of the burn wound. The clinical evaluation and initial care of a burn wound is described and includes an assessment of burn depth, determining the need for escharatomy and daily burn wound care. Burns can be topical or surgical. Topical burn wounds require choice in the use of antibiotics. Considerations and techniques for surgical burn wound management are described and include early excision and grafting, wound excision, skin grafting, graft and donor-site dressings, postoperative wound care, biologic dressings and skin substitutes, allograft and xenograft skin, cultured epidermal autografts, and skin substitutes. Figures show the two distinct layers of the skin, various types of burns, and both fascial and tangential excision of burn wounds. This review contains 12 figures, 11 tables, and 61 references. Keywords: Burn wound, graft, partial-thickness, full-thickness, dermis, epidermis, sloughing, dressing

Management of the Burn Wound

Current approaches to burn management are based on an understanding of the biology and physiology of human skin and the pathophysiology of the burn wound. The clinical evaluation and initial care of a burn wound is described and includes an assessment of burn depth, determining the need for escharatomy and daily burn wound care. Burns can be topical or surgical. Topical burn wounds require choice in the use of antibiotics. Considerations and techniques for surgical burn wound management are described and include early excision and grafting, wound excision, skin grafting, graft and donor-site dressings, postoperative wound care, biologic dressings and skin substitutes, allograft and xenograft skin, cultured epidermal autografts, and skin substitutes. Figures show the two distinct layers of the skin, various types of burns, and both fascial and tangential excision of burn wounds. This review contains 12 figures, 11 tables, and 61 references. Keywords: Burn wound, graft, partial-thickness, full-thickness, dermis, epidermis, sloughing, dressing

The burn comb model revisited.

The burn comb model is a well-established model for studying secondary burn progression. It creates four rectangular burn surfaces intercalated by three unburned zones prone to secondary burn progression. While burn progression is a tri-dimensional phenomenon, of which the vertical extension from the superficial to deeper tissue layer is clinically most relevant, the models initial focus was mainly on the horizontal surface extension within interspaces. The aim of this study is to evaluate the correlation between horizontal surface and vertical depth burn progression. 24 large (400-450 g) Wistar male rats underwent standardized burn injuries using a burn comb. Laser Doppler flowmetry to assess perfusion, planimetric evaluation of burn progression within interspaces and histological analyses assessing burn depth were performed before burn induction (baseline; BL) and after 1 h, as well as after 1, 4, and 7 days. Histological burn depth was graded from superficial (1) to the subcutaneous layer (5). Furthermore, final scarring time and contracture rate were also assessed. The burn comb resulted in consistent and uniform superficial burns (mean ± SEM burn depth score: 2 ± 0; hour 1) separated by intact but critically perfused interspaces (63 ± 1% of BL; p < 0.05 vs. BL). Tissue damage significantly progressed to the deep dermis within the first day (burn depth score 4.3 ± 0.2; p < 0.05 vs. hour 1), while significant interspace necrosis at the surface did not develop within this time period (4 ± 3% of interspace necrosis; p n.s vs. hour 1). However, interspace necrosis was observed at day 4 (83 ± 3%; p < 0.05 vs. hour 1) and further progressed until day 7 (94 ± 2%; p < 0.05 vs. hour 1). This study shows the limits of the burn comb model originally described with a discrepancy between horizontal surface and vertical depth progression of the burn injury. We herein propose a necessary refinement of this model to adequately evaluate vertical depth progression using a histological score. This revisited approach focusing on assessment of depth progression of the burn will allow a better evaluation of experimental burn treatments in future.

Interobserver reliability of laser speckle contrast imaging in the assessment of burns

ObjectivesLaser speckle contrast imaging (LSCI) is an emerging technique for the assessment of burns in humans and interobserver differences have not been studied. The aim of this study was to compare assessments of perfusion images by different professional groups regarding (i) perfusion values and (ii) burn depth assessment. MethodsTwelve observers without LSCI experience were included. The observers were evenly recruited from three professional groups: plastic surgeons with experience in assessing burns, nurses with experience in treating burns, and junior doctors with limited experience of burns. Ten cases were included. Each case consisted of one digital photo of the burn with a pre-marked region of interest (ROI) and two unmarked perfusion images of the same area. The first and the second perfusion image was from 24h and 72–96h after injury, respectively. The perfusion values from both perfusion images were used to generate a LSCI recommendation based on the perfusion trend (the derivative between the two perfusion values). As a last step, each observer was asked to estimate the burn depth using their clinical experience and all available information. Intraclass correlation (ICC) was calculated between the different professional groups and among all observers. ResultsPerfusion values and perfusion trends between all observers had an ICC of 0.96 (95% CI 0.91–0.99). Burn depth assessment by all observers yielded an ICC of 0.53 (95% CI: 0.31–0.80) and an accuracy of 0.53 (weighted kappa). LSCI recommendations generated by all observers had an ICC of 0.95 (95% CI: 0.90–0.99). ConclusionObservers can reliably identify the same ROI, which results in observer-independent perfusion measurements, irrespective of burn experience. Extensive burn experience did not further improve burn depth assessment. The LSCI recommendation was more accurate in all professional groups. Introducing LSCI measurements would be likely improve early assessment of burns.

In vivo dual-scale photoacoustic surveillance and assessment of burn healing.

Accurate diagnoses of superficial and deep dermal burns are difficult to make even by experienced investigators due to slight differences in dermis damage. Many imaging technologies have been developed to improve the burn depth assessment. But these imaging tools have limitations in deep imaging or resolving ability. Photoacoustic imaging is a hybrid modality combining optical and ultrasound imaging that remains high resolution in deep imaging depth. In this work, we used dual-scale photoacoustic imaging to noninvasively diagnose burn injury and monitor the burn healing. Real-time PACT provided cross-sectional and volumetric images of the burn region. High-resolution PAM allowed for imaging of angiogenesis on the hyperemic ring. A long-term surveillance was also performed to assess the difference between the two damage degrees of burn injuries. Our proposed method suggests an effective tool to diagnose and monitor burn injury.

Full-field burn depth detection based on near-infrared hyperspectral imaging and ensemble regression.

The accurate and instant diagnosis of burn severity is always the key point of optimal wound management and clinical treatment. However, the accuracy of burn depth assessment is low via visual inspection and lacks a quantitative measurement. In this work, a full-field burn depth detection system is proposed using the near-infrared hyperspectral imaging with the ensemble regression. The rotational feature subspace ensemble regression is introduced to establish a complex regression model between the hyperspectral imaging data and the burn depth. By the in vivo measurement of a porcine model, the method can get the average relative error about 7% for the burn depth measurement, which demonstrates that the proposed method can perform an accurate full-field assessment of burn depth and provide more practical references for clinicians.

500 Treatment of Burns over 10%TBSA with Natural Silk

During the treatment of superficial burn injuries patients are often confronted with painful dressing changes. Therefor we often treat these wounds with very expensive materials like nylon mesh combined with animal collagen that can stay on the wound and slowly peel off during re-epithelialization. Due to our good experiences with the treatment of small burn injuries with pure natural silk as cost-efficient material, we now also started treating large burn injuries for the first time with silk. Altogether 27 patients with superficial burn injuries over 10% (10.5-49%) of the body surface area were treated with pure silk. Afterwards the wound healing, number of operations and the patient’s satisfaction were evaluated. In 24 of 27 cases all wounds healed unproblematically without dressing change, infection or further operations. In three cases, mostly chemical burns, initial burn depth assessment was not correct and skin grafting became necessary during wound healing. All patients were satisfied with the treatment, though stated a feeling of stiffness in dressings covering joints. Altogether silk is an interesting, cost-efficient material for the treatment of superficial burns. During the treatment of larger areas a careful wound depth evaluation is very important to avoid infections and further operations during the wound healing. Silk has become the standard of care in our clinic for the treatment of superficial burns.

94 Evaluating Quality in Burn Care: Limitations of the Nationwide Readmission Database

Hospital readmission data may be helpful in identifying risk factors leading to higher costs of care or undesired outcomes. Few studies have examined readmission rates in the traumatic injury population, with even fewer examining the applicability to the adult burn population. The 2014 Nationwide Readmissions Database (NRD) was queried for 363 burn-specific ICD-9 CM codes and filtered by age and readmission status to capture the adult burn population presenting between January 1 and December 31, 2014. Note that the NRD does not include planned readmissions in the dataset captured. Univariate and multivariate logistical regression models were developed to determine readmission likelihood. A total of 26,719 burn patients were identified in the database with 1,209 all-cause unscheduled readmissions. Initial readmission analysis of demographics and comorbidities identified several readmission correlations in agreement with previous studies. However, 48% of all burn readmissions underwent an excision and grafting procedure on readmission. Additionally the highest readmission likelihood (3.14; 2.45–4.02) was seen in the highest volume centers, those seeing over 350 burn patients per year. The database was then filtered to remove those undergoing excision and grafting on readmission and readmission relationships were found to change considerably. Non-operative management on initial admission was found to have the strongest correlation with readmission (6.06; 4.55–10.0), followed by discharge AMA (3.65; 2.64–5.05). Hospital annual burn patient volume was found to not be significantly correlated with readmission. Non-operative management of burn wounds continues to fail a certain percentage of the time in the absence of definitive ways to assess burn depth. However, increases in readmission rates can be decoupled from hospital volumes when accurate patient characterization within the database is performed. Readmission coding accuracy represents a limitation of the NRD database which should not be overlooked when examining the burn population. Understanding the limitations of national databases with regards to assessing quality in Burn patients.

Burn image segmentation based on Mask Regions with Convolutional Neural Network deep learning framework: more accurate and more convenient

BackgroundBurns are life-threatening with high morbidity and mortality. Reliable diagnosis supported by accurate burn area and depth assessment is critical to the success of the treatment decision and, in some cases, can save the patient’s life. Current techniques such as straight-ruler method, aseptic film trimming method, and digital camera photography method are not repeatable and comparable, which lead to a great difference in the judgment of burn wounds and impede the establishment of the same evaluation criteria. Hence, in order to semi-automate the burn diagnosis process, reduce the impact of human error, and improve the accuracy of burn diagnosis, we include the deep learning technology into the diagnosis of burns.MethodThis article proposes a novel method employing a state-of-the-art deep learning technique to segment the burn wounds in the images. We designed this deep learning segmentation framework based on the Mask Regions with Convolutional Neural Network (Mask R-CNN). For training our framework, we labeled 1150 pictures with the format of the Common Objects in Context (COCO) data set and trained our model on 1000 pictures. In the evaluation, we compared the different backbone networks in our framework. These backbone networks are Residual Network-101 with Atrous Convolution in Feature Pyramid Network (R101FA), Residual Network-101 with Atrous Convolution (R101A), and InceptionV2-Residual Network with Atrous Convolution (IV2RA). Finally, we used the Dice coefficient (DC) value to assess the model accuracy.ResultThe R101FA backbone network gains the highest accuracy 84.51% in 150 pictures. Moreover, we chose different burn depth pictures to evaluate these three backbone networks. The R101FA backbone network gains the best segmentation effect in superficial, superficial thickness, and deep partial thickness. The R101A backbone network gains the best segmentation effect in full-thickness burn.ConclusionThis deep learning framework shows excellent segmentation in burn wound and extremely robust in different burn wound depths. Moreover, this framework just needs a suitable burn wound image when analyzing the burn wound. It is more convenient and more suitable when using in clinics compared with the traditional methods. And it also contributes more to the calculation of total body surface area (TBSA) burned.

Discordance between histologic and visual assessment of tissue viability in excised burn wound tissue

The regenerative capacity of burn wounds, and the need for surgical intervention, depends on wound depth. Clinical visual assessment is considered the gold standard for burn depth assessment but it remains a subjective and inaccurate method for tissue evaluation. The purpose of this study was to compare visual assessment with microscopic and molecular techniques for human burn depth determination, and illustrate differences in the evaluation of tissue for potential regenerative capacity. Using intraoperative visual assessment, patients were identified as having deep partial thickness or full thickness burn wounds. Tangential excisions of burn tissue were processed with hematoxylin and eosin to visualize tissue morphology, lactate dehydrogenase assay to ascertain cellular viability, and Keratin-15 and Ki67 to identify epidermal progenitor cells and proliferative capacity, respectively. RNA from deep partial and full thickness burn tissue as well as normal tissue controls were submitted for RNA sequencing. Lactate dehydrogenase, Keratin-15, and Ki67 were found throughout the excised burn wound tissue in both deep partial thickness burn tissues and in the second tangential excision of full thickness burn tissues. RNA sequencing demonstrated regenerative capacity in both deep partial and full thickness burn tissue, however a greater capacity for regeneration was present in deep partial thickness compared with full thickness burn tissues. In this study, we highlight the discordance that exists between the intraoperative clinical identification of burn injury depth, and microscopic and molecular determination of viability and regenerative capacity. Current methods utilizing visual assessment for depth of injury are imprecise, and can lead to removal of viable tissue. Additionally, hematoxylin and eosin microscopic analysis should not be used as the sole method in research or clinical determination of depth, as there are no differences in staining between viable and nonviable tissue.