A Modified Beer-Lambert Model of Skin Diffuse Reflectance for the Determination of Melanin Pigments

Hani, Ahmad Fadzil Mohamad; Nugroho, Hanung Adi; Noor, Nadiah Mohd; Rahim, K. F.; Baba, Roshidah

doi:10.1007/978-3-642-21729-6_101

Cited by 2 publications

(4 citation statements)

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“…Also, Indians apparently have a lower difference in the mean levels of the two peaks defined by P1 and P2 baselines as depicted in Fig 4C. On the same note, Malays have slightly lower peak differential compared to the Chinese ethnic. As shown in Fig 6C, in the UV region (150-400nm), Indians usually return a lower reading in the reflectance percentages due to the abundant absorption from melanin in the skin as reported in recent works as well [36], comparably similar in previous studies with Malaysian subjects [35]. In the VIS region, Indians also show a collectively lower reflectance reading which is due to the darker pigmentation in the skin.…”

Section: Raw Data Analysis: Decomposing Confounding Factorssupporting

confidence: 88%

“…Since we were able to maintain consistency of the output readings, this configuration was standardized throughout the measurements during the data collection period. Based on the raw appearance of the data, different ethnicities exhibit noticeable difference especially in the visible region, as shown in the VIS section (390-700 nm) in Fig 4. This is intuitively the case as skin tone differences are usually discernible by the majority of people from a normal visual cue, as Indians generally have a darker skin tone than Malays, and the Chinese generally have a fairer complexion, as shown in Fig 4. In quantitative terms, the skin types are measured in terms of Fitzpatrick skin phototypes (SPTs), where Asians usually have types III, IV and V skin, where these classifications correspond to higher to lower reflectance percentages [35].…”

Section: Raw Data Analysis: Decomposing Confounding Factorsmentioning

confidence: 99%

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Precursors to non-invasive clinical dengue screening: Multivariate signature analysis of in-vivo diffuse skin reflectance spectroscopy on febrile patients in Malaysia

et al. 2020

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Dengue diagnostics have come a long way. Attempts at breaking away from lab-oriented dengue detection, such as NS1 antigen, IgM or IgG antibodies detection have extensively received numerous coverage. As a result, rapid detection tests (RDTs) have started to gain inroads in medical practice. Rapid detection tests notwithstanding, analysis of blood serum is still a relatively complicated task. This includes the necessity of phlebotomy, centrifugation for blood serum, and other reagent-based tests. Therefore, a non-invasive method of dengue detection was considered. In this study, we present the utility of diffuse reflectance skin spectroscopy (bandwidth of 200-2500nm) on the forearm during the triaging period for dengue screening potential. This is performed with multivariate analysis of 240 triaged febrile/suspected dengue patients. The data is then scrutinized for its clinical validity to be included as either confirmed or probable dengue, or a control group. Based on discriminant analysis of several data normalization models, we can predict the patients' clinical denguepositivity at ranges of accuracy between~93-98% depending on mode of the data, with a probably optimal sensitivity and specificity to the clinical diagnosis of~89% and~100% respectively. From the outcomes of this study, we recommend further trials with cautious optimism. With these findings, it is hoped that the elusive non-invasive detection of tropical diseases may gain platform in the near future.

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Section: Raw Data Analysis: Decomposing Confounding Factorssupporting

confidence: 88%

Section: Raw Data Analysis: Decomposing Confounding Factorsmentioning

confidence: 99%

Precursors to non-invasive clinical dengue screening: Multivariate signature analysis of in-vivo diffuse skin reflectance spectroscopy on febrile patients in Malaysia

et al. 2020

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“…In the human body, blood perfusion parameters can be measured through the skin [2], [3], a measurement referred to as skin blood perfusion (SBP). This is possible due to the interaction between light and skin chromophores [4]. The most predominant chromophore in the dermis is the hemoglobin, whose function is to carry oxygen [4], [5].…”

Section: Introductionmentioning

confidence: 99%

“…This is possible due to the interaction between light and skin chromophores [4]. The most predominant chromophore in the dermis is the hemoglobin, whose function is to carry oxygen [4], [5]. SBP measurements provide information about some clinical parameters such as oxygen saturation [6]- [8], and hemoglobin concentration changes [7], [9], [10].…”

Section: Introductionmentioning

confidence: 99%

Contactless Skin Blood Perfusion Imaging via Multispectral Information, Spectral Unmixing and Multivariable Regression

Granados-Castro,

Gutierrez-Navarro,

Mejia-Rodriguez

et al. 2024

IEEE Open J. Signal Process.

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Noninvasive methods for assessing in-vivo skin blood perfusion parameters, such as hemoglobin oxygenation, are crucial for diagnosing and monitoring microvascular diseases. This approach is particularly beneficial for patients with compromised skin, where standard contact-based clinical devices are inappropriate. For this goal, we propose the analysis of multimodal data from an occlusion protocol applied to 18 healthy participants, which includes multispectral imaging of the whole hand and reference photoplethysmography information from the thumb. Multispectral data analysis was conducted using two different blind linear unmixing methods: principal component analysis (PCA), and extended blind endmember and abundance extraction (EBEAE). Perfusion maps for oxygenated and deoxygenated hemoglobin changes in the hand were generated using linear multivariable regression models based on the unmixing methods. Our results showed high accuracy, with R 2 -adjusted values, up to 0.90±0.08. Further analysis revealed that using more than four characteristic components during spectral unmixing did not improve the fit of the model. Bhattacharyya distance results showed that the fitted models with EBEAE were more sensitive to hemoglobin changes during occlusion stages, up to four times higher than PCA. Our study concludes that multispectral imaging with EBEAE is effective in quantifying changes in oxygenated hemoglobin levels, especially when using 3 to 4 characteristic components. Our proposed method holds promise for the noninvasive diagnosis and monitoring of superficial microvascular alterations across extensive anatomical regions.INDEX TERMS skin blood perfusion, hemoglobin, multispectral imaging, photoplethysmography, spectral unmixing.

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A Modified Beer-Lambert Model of Skin Diffuse Reflectance for the Determination of Melanin Pigments

Cited by 2 publications

References 0 publications

Precursors to non-invasive clinical dengue screening: Multivariate signature analysis of in-vivo diffuse skin reflectance spectroscopy on febrile patients in Malaysia

Precursors to non-invasive clinical dengue screening: Multivariate signature analysis of in-vivo diffuse skin reflectance spectroscopy on febrile patients in Malaysia

Contactless Skin Blood Perfusion Imaging via Multispectral Information, Spectral Unmixing and Multivariable Regression

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