Visualization of old bruises in children: Use of violet light to record long-term bruises

Examining the use of alternative light sources in medico-legal assessments of blunt-force trauma: a systematic review

The ability to analyze blunt-force trauma is crucial for deciphering valuable clues concerning mechanisms of injury and as evidence for medico-legal investigations. The use of alternate light sources (ALS) has been studied over the past decade, and is proposed to outperform conventional white light (CWL) during bruise assessments. In response to the growing interest of the technology worldwide, a systematic review of the literature was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) to address the ability of ALS to detect and visualize bruising. From an initial 4055 records identified, ten studies met the eligibly criteria and were selected for this review. Evaluation also included a novel framework, referred to as SPICOT, to further systematically assess both scientific evidence and risk of bias in forensic literature. Analysis reveals that narrowband wavelengths within in the infrared or ultraviolet spectral ranges do not significantly outperform CWL in visualizing or detecting bruising. However, wavelengths within the visible spectrum, particularly 415 nm combined with longpass or bandpass yellow filters, are more effective. However, the majority of selected studies only address the sensitivity of ALS, and therefore, results may only be considered valid when the location of a bruise is known. Further investigation is required to understand the specificity of ALS, in particular how the use of topical cosmetic products, previous wounds/scar-tissue, tattoos, moles and freckles may affect detection. The ethical concern regarding the interpretation of enhanced visualized trauma should also be considered in prospect discussions prior to implementing ALS into routine practice. Nevertheless, this review finds that narrowband ALS within the visible spectrum demonstrates potential for improved injury documentation, outperforming CWL in the detection and visualization of bruising.

Visibility of inflicted bruises by alternate light: Results of a randomized controlled trial

Difficulty visualizing bruises resulting from interpersonal violence, especially in individuals with dark skin, contributes to disparities in access to justice. The purpose of this analysis was to compare bruise visibility of detected injuries using white light versus alternate light sources (ALS). Visibility was assessed using the 5-point Bruise Visibility Scale (BVS) for white light and the ALS Visibility Scale (AVS) for ALS. Bruises were induced using controlled application of a paintball to the upper arm on 157 healthy adults across six skin color categories. Using a crossover design, the light source used first to assess the bruise (white light or ALS) was randomized. Each bruise was examined up to 21 times over 4 weeks using white light and 10 combinations of wavelengths (350 nanometer [nm] - 535 nm) and colored filters (yellow, orange, and red). Multilevel modeling was used to analyze the repeated measures data with a total 20,103 bruise assessments. Results revealed 415 nm with yellow filter resulted in an almost 0.5-point increase in BVS/AVS score across all skin colors (Estimate = 0.46; 95% CI: 0.43, 0.49; p < 0.001), a clinically significant improvement in ability to visualize bruises. Conversely, 515 nm (Estimate = -0.80; 95% CI: -0.84, -0.76; p < 0.001) and 535 nm (Estimate = -0.64, 95% CI: -0.67, -0.60; p < 0.001) with red filter resulted in more than 0.5-point decrease in BVS/AVS score. The use of ALS is supported by the data and results in improved bruise visibility during medical forensic examinations.

Improving the Forensic Documentation of Injuries Through Alternate Light: A Researcher-Practitioner Partnership

An alternate light source (ALS) is a practitioner-driven technology that can potentially improve the documentation of injuries among victims of interpersonal violence. However, evidence-based guidelines are needed to incorporate and document an ALS skin assessment into a forensic medical examination that accurately reflects the science, context of forensic nursing practice, trauma-informed responses, and potential impact on criminal justice stakeholders. This article introduces the forensic nursing community to a current translation-into-practice project focused on developing and evaluating an ALS implementation program to improve the assessment and documentation of bruises among adult patients with a history of interpersonal violence. Our researcher-practitioner collaboration uses theory-based approaches that consider both the developed program's practice context and stakeholder impact. The goal is to provide evidentiary support for adult victims of violence and a more equitable forensic nursing practice that benefits diverse patient populations.

A multichannel color filter with the functions of optical sensor and switch

This paper reports a multichannel color filter with the functions of optical sensor and switch. The proposed structure comprises a metal-insulator-metal (MIM) bus waveguide side-couples to six circular cavities with different sizes for filtering ultra-violet and visible lights into individual colors in the wavelength range of 350-700 nm. We used the finite element method to analyze the electromagnetic field distributions and transmittance properties by varying the structural parameters in detail. The designed plasmonic filter takes advantage of filtering out different colors since the light-matter resonance and interference between the surface plasmon polaritons (SPPs) modes within the six cavities. Results show that the designed structure can preferentially select the desired colors and confine the SPPS modes in one of the cavities. This designed structure can filter eleven color channels with a small full width at half maximum (FWHM) ~ 2 nm. Furthermore, the maximum values of sensitivity, figure of merit, quality factor, dipping strength, and extinction ratio can achieve of 700 nm/RIU, 350 1/RIU, 349.0, 65.04%, and 174.50 dB, respectively, revealing the excellent functions of sensor performance and optical switch, and offering a chance for designing a beneficial nanophotonic device.

Beyond the visible spectrum - applying 3D multispectral full-body imaging to the VirtoScan system

Multispectral photography offers a wide range of applications for forensic investigations. It is commonly used to detect latent evidence and to enhance the visibility of findings. Additionally, three-dimensional (3D) full-body documentation has become much easier and more affordable in recent years. However, the benefits of performing 3D imaging beyond the visible (VIS) spectrum are not well known, and the technique has not been widely used in forensic medical investigations. A multicamera setup was used to employ multispectral photogrammetry between 365 and 960 nm in postmortem investigations. The multicamera setup included four modified digital cameras, ultraviolet (UV) and near-infrared (NIR) light sources and supplemental lens filters. Full-body documentation was performed in conjunction with the use of a medical X-ray computed tomography (CT) scanner to automate the imaging procedure. Textured 3D models based on multispectral datasets from four example cases were reconstructed successfully. The level of detail and overall quality of the 3D reconstructions varied depending on the spectral range of the image data. Generally, the NIR datasets showed enhanced visibility of vein patterns and specific injuries, whereas the UV-induced datasets highlighted foreign substances on the skin. Three-dimensional multispectral full-body imaging enables the detection of latent evidence that is invisible to the naked eye and allows visualization, documentation and analysis of evidence beyond the VIS spectrum.

Alternate Light Source Findings of Common Topical Cosmetics and Three Removal Methods

INTRODUCTION

Alternate light sources (ALSs) are a tool used by forensic nurses to aid in the physical examination of patients. Prior research has shown some topical makeup products absorb alternate light similar to the absorption noted in bruises. Therefore, the purposes of this study were (a) to further examine the ALS findings of multiple brands and types of makeup products and (b) to compare the efficacy of three methods of makeup removal.

METHODS

Fourteen makeup products were applied to the forearms of 100 healthy adult volunteers with varying skin tones and then assessed under white light, six alternate light wavelengths, and three color filters, producing 19 total wavelength-and-filter combinations. The results were recorded before and after removal procedures by forensic nurse examiners who were blinded to the removal method. A three-arm randomized controlled trial of makeup removal methods (soap and water, isopropyl alcohol swab, makeup removal wipe) was conducted with the participants.

RESULTS

All 14 makeup products produced absorption in at least 10% of the observations. Fluorescence was observed in more than 10% of the observations for only two products. After product removal, four products continued to produce statistically significant absorption findings when viewed under an ALS. One product produced significant fluorescence after removal procedures. There were no statistically significant differences between the removal methods noted in any of these analyses.

CONCLUSION

Our findings support the importance of using alternate light as one component of a comprehensive forensic examination, including history taking and physical examination.

Detection of Inflicted Bruises by Alternate Light: Results of a Randomized Controlled Trial

Bruises are often difficult to detect on victims of violence, potentially impacting investigation and prosecution. The purpose of our randomized controlled trial was to measure the effectiveness of an alternate light source (ALS) within visible and long ultraviolet spectrums at improving bruise detection compared to white light over time. We also examined the effects of skin color, age, gender, localized fat, and injury mechanism on bruise detection. Participants included 157 healthy adults with balanced sampling across six skin color categories. Bruises were created under the controlled application of a paintball pellet and dropped weight to one upper and lower arm, respectively. Using a crossover design, both bruises were examined 21 times over 4 weeks. Ten different wavelength (350–535 nm) and filter (yellow, orange, red) combinations were used. Multilevel models were used to analyze 2903 examinations on both upper and lower arms. Results in multivariable models showed after controlling for other covariates 415 and 450 nm using a yellow filter had greater odds of detecting evidence of bruising than white light (Upper Arm: 415 nm: OR = 5.34, 95% CI: 4.35–6.56; 450 nm: OR = 4.08, 95% CI: 3.36–4.96). Under either light source, being female and having more localized fat had increased odds of detecting bruises created by the dropped weight (female: OR = 2.96, 95% CI: 2.37–3.70; fat: OR = 1.21, 95% CI: 1.09–1.34). Our results support ALS as an appropriate tool to enhance concurrent physical assessment of bruises in the presence of known history of injury. Future development and evaluation of clinical practice guidelines for ALS application are needed.

Bruise detection and visibility under alternate light during the first three days post-trauma

INTRODUCTION

Cutaneous bruises are often hard to detect particularly on individuals with a darker complexion. Researchers and federal agencies have recommended the use of alternate light to aide in the assessment of subtle injury. However, studies are limited in their evaluation of wavelength performance during the first few days of bruise healing. The purpose of this pilot study was to examine whether an alternate light source (ALS) improves detection of bruises when compared to normal light typical of clinical practice during the first three days following induction.

METHODS

A sample of eight healthy adults between 22 and 36 years of age with diverse skin color were recruited for this study. One bruise was induced on each participant by dropping a 4-oz (113g) steel ball through a 5-ft (1.5 m) vertical pipe onto the anterior surface of the forearm. Using the ALS, bruises were assessed under 14 different combinations of ultraviolet and short narrowband visible wavelengths and filters along with overhead fluorescent "examination" lighting. Participants were examined 3 to 4 times per day at approximately 4-h intervals for three consecutive days post induction.

RESULTS

Repeated bruise assessments on 8 subjects resulted in 59 bruise assessments and 885 total observations under the different wavelengths and filters combinations. A bruise was detectable in 46 (78%) of the assessments, with bruise ages ranging from 30 min to 57 h. Twenty (34%) bruises not detectable under normal light were visible with ASL. Multilevel modeling revealed a strong association between time and detection for shorter wavelengths, such as 365 nm (ultraviolet) and 450 nm.

CONCLUSION

The results of our study suggest alternate light is more likely to detect faint bruises than normal lighting during the first three days post injury. However, more research is needed to determine which wavelengths and filter combinations are most effective during that time frame.

Evaluation of a model of bruising in pigmented skin for investigating the potential for alternate light source illumination to enhance the appearance of bruises by photography of visible and infrared light

The purpose of this study was to evaluate the ability of alternate light source illumination to enhance bruises in pigmented skin. Previous work was limited to simulating bruises in non-pigmented (Caucasoid type) skin by injecting blood into pigskin. In this study, it was investigated if adding a layer of melanin to the surface of the skin would simulate pigmented skin. The study included evaluating the use of a filter that transmitted infrared light (wavelength greater than 720 nm) in place of the recommended visible light filters for the alternate light sources. The results obtained using pigskin with a layer of melanin were almost the same as results using the naturally pigmented goat ear. This indicated adding a layer of melanin could be used as a model for pigmented skin in this simulation of fresh bruising. Comparing the pigskin without melanin with pigskin with melanin revealed that the optimal light source to enhance the appearance of bruising, simulated by injection of blood, changed from violet to blue-green. Using the infrared transmitting filter resulted in greater enhancement than using the alternate light sources with their recommended visible light filter. The advantage of using the infrared transmitting filter was greater with the pigskin coated with melanin and the naturally pigmented goat ears than in the non-pigmented pigskin, however, the results remain to be validated using real bruises in naturally pigmented human skin.

A comparison of four different imaging modalities - Conventional, cross polarized, infra-red and ultra-violet in the assessment of childhood bruising

Background

It is standard practice to image concerning bruises in children. We aim to compare the clarity and measurements of bruises using cross polarized, infra-red (IR) and ultra-violet (UV) images to conventional images.

Methods

Children aged <11 years with incidental bruising were recruited. Demographics, skin and bruise details were recorded. Bruises were imaged by standard protocols in conventional, cross-polarized, IR and UV lights. Bruises were assessed in vivo for contrast, uniformity and diffuseness, and these characteristics were then compared across image modalities. Color images (conventional, cross polarized) were segmented and measured by ImageJ. Bruises of grey scale images (IR, UV) were measured by a ‘plug in’ of ImageJ. The maximum and minimum Feret's diameter, area and aspect ratio, were determined. Comparison of measurements across imaging modalities was conducted using Wilcoxon rank sum tests and modified Bland-Altman graphs. Significance was set at p < 0.05.

Results

Twenty five children had 39 bruises. Bruises that were of low contrast, i.e. difficult to distinguish from surrounding skin, were also more diffuse, and less uniformity in vivo. Low contrast bruises were best seen on conventional and cross-polarized images and less distinctive on IR and UV images. Of the 19 bruises visible in all modalities, the only significant difference was maximum and minimum Feret's diameters and area were smaller on IR compared to conventional images. Aspect ratios were not affected by the modality.

Conclusions

Conventional and cross-polarized imaging provides the most consistent bruise measurement, particularly in bruises that are not easily distinguished from surrounding skin visually.

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Diffuse bruises may be measured on conventional & cross polarized imaging.

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Infrared or ultraviolet imaging may not show bruises which are difficult to see in vivo.

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Measurements of bruises using infrared imaging may be smaller than other modalities.