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Kohnke J, Pattberg K, Nensa F, Kuhlmann H, Brenner T, Schmidt K, Hosch R, Espeter F. A proof of concept for microcirculation monitoring using machine learning based hyperspectral imaging in critically ill patients: a monocentric observational study. Crit Care 2024; 28:230. [PMID: 38987802 PMCID: PMC11238485 DOI: 10.1186/s13054-024-05023-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Accepted: 07/06/2024] [Indexed: 07/12/2024] Open
Abstract
BACKGROUND Impaired microcirculation is a cornerstone of sepsis development and leads to reduced tissue oxygenation, influenced by fluid and catecholamine administration during treatment. Hyperspectral imaging (HSI) is a non-invasive bedside technology for visualizing physicochemical tissue characteristics. Machine learning (ML) for skin HSI might offer an automated approach for bedside microcirculation assessment, providing an individualized tissue fingerprint of critically ill patients in intensive care. The study aimed to determine if machine learning could be utilized to automatically identify regions of interest (ROIs) in the hand, thereby distinguishing between healthy individuals and critically ill patients with sepsis using HSI. METHODS HSI raw data from 75 critically ill sepsis patients and from 30 healthy controls were recorded using TIVITA® Tissue System and analyzed using an automated ML approach. Additionally, patients were divided into two groups based on their SOFA scores for further subanalysis: less severely ill (SOFA ≤ 5) and severely ill (SOFA > 5). The analysis of the HSI raw data was fully-automated using MediaPipe for ROI detection (palm and fingertips) and feature extraction. HSI Features were statistically analyzed to highlight relevant wavelength combinations using Mann-Whitney-U test and Benjamini, Krieger, and Yekutieli (BKY) correction. In addition, Random Forest models were trained using bootstrapping, and feature importances were determined to gain insights regarding the wavelength importance for a model decision. RESULTS An automated pipeline for generating ROIs and HSI feature extraction was successfully established. HSI raw data analysis accurately distinguished healthy controls from sepsis patients. Wavelengths at the fingertips differed in the ranges of 575-695 nm and 840-1000 nm. For the palm, significant differences were observed in the range of 925-1000 nm. Feature importance plots indicated relevant information in the same wavelength ranges. Combining palm and fingertip analysis provided the highest reliability, with an AUC of 0.92 to distinguish between sepsis patients and healthy controls. CONCLUSION Based on this proof of concept, the integration of automated and standardized ROIs along with automated skin HSI analyzes, was able to differentiate between healthy individuals and patients with sepsis. This approach offers a reliable and objective assessment of skin microcirculation, facilitating the rapid identification of critically ill patients.
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Affiliation(s)
- Judith Kohnke
- Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
- Institute for Artificial Intelligence in Medicine (IKIM), University Hospital Essen, Essen, Germany
| | - Kevin Pattberg
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Felix Nensa
- Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
- Institute for Artificial Intelligence in Medicine (IKIM), University Hospital Essen, Essen, Germany
| | - Henning Kuhlmann
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Thorsten Brenner
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Karsten Schmidt
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - René Hosch
- Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany
- Institute for Artificial Intelligence in Medicine (IKIM), University Hospital Essen, Essen, Germany
| | - Florian Espeter
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Essen, University Duisburg-Essen, Essen, Germany.
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Huo D, Wang J, Qian Y, Yang YH. Learning to Recover Spectral Reflectance From RGB Images. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 2024; 33:3174-3186. [PMID: 38687649 DOI: 10.1109/tip.2024.3393390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
This paper tackles spectral reflectance recovery (SRR) from RGB images. Since capturing ground-truth spectral reflectance and camera spectral sensitivity are challenging and costly, most existing approaches are trained on synthetic images and utilize the same parameters for all unseen testing images, which are suboptimal especially when the trained models are tested on real images because they never exploit the internal information of the testing images. To address this issue, we adopt a self-supervised meta-auxiliary learning (MAXL) strategy that fine-tunes the well-trained network parameters with each testing image to combine external with internal information. To the best of our knowledge, this is the first work that successfully adapts the MAXL strategy to this problem. Instead of relying on naive end-to-end training, we also propose a novel architecture that integrates the physical relationship between the spectral reflectance and the corresponding RGB images into the network based on our mathematical analysis. Besides, since the spectral reflectance of a scene is independent to its illumination while the corresponding RGB images are not, we recover the spectral reflectance of a scene from its RGB images captured under multiple illuminations to further reduce the unknown. Qualitative and quantitative evaluations demonstrate the effectiveness of our proposed network and of the MAXL. Our code and data are available at https://github.com/Dong-Huo/SRR-MAXL.
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Bachir W. Diffuse transmittance visible spectroscopy using smartphone flashlight for photoplethysmography and vital signs measurements. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 303:123181. [PMID: 37506454 DOI: 10.1016/j.saa.2023.123181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 07/06/2023] [Accepted: 07/20/2023] [Indexed: 07/30/2023]
Abstract
Photoplethysmography (PPG), with its wide range of applications, has become one of the most promising modalities for healthcare monitoring technology. In this work, we present a new PPG measurement technique based on diffuse transmittance spectroscopy (DTS) with the help of a smartphone built-in flashlight as an alternative broadband light source. The blood Volume Pulse (BVP) signal was extracted from recorded transmittance spectra at 620 nm. The results were compared with the ground truth and conventional contact finger PPG sensors. A very high correlation was found between the diffuse transmittance signal and the reference PPG signals (r = 0.997, p < 0.0001). The accuracy and root mean square error (RMSE) were 99.23% and 0.8 bpm, respectively. In addition, a Bland-Altman analysis showed a good agreement between both techniques, with a very small bias between mean paired differences of heart rate observations. A simple forward model for diffuse transmittance spectra for different levels of blood oxygen saturation is developed and supported by experimental measurements. It was also found that blood oxygen saturation (SpO2) can be estimated with the aid of DTS based smartphone flash by tracking the wavelength corresponding to the oxygenation level in the visible range between orange and red regions of the visible spectrum particularly in the range between 610 and 635 nm for 26 healthy subjects. 624 nm on average seems to be the wavelength that corresponds with the normal blood oxygenation level. These findings show the potential of DTS PPG to reliably extract cardiac frequency and estimate SpO2 with adequate accuracy. The results also demonstrate the capability of smartphone flash as a miniature visible light source for recording multispectral PPG signals and quantifying vital signs in the transmission mode at the fingertip with acceptable signal quality over a wide range of wavelengths from 550 nm to 650 nm.
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Affiliation(s)
- Wesam Bachir
- Institute of Metrology and Biomedical Engineering, Faculty of Mechatronics, Warsaw University of Technology, Św. A. Boboli 8 St., Warsaw 02-525, Poland; Biomedical Photonics Laboratory, Higher Institute for Laser Research and Applications, Damascus University, Damascus, Syria
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Hou H, Mitbander R, Tang Y, Azimuddin A, Carns J, Schwarz RA, Richards-Kortum RR. Optical imaging technologies for in vivo cancer detection in low-resource settings. CURRENT OPINION IN BIOMEDICAL ENGINEERING 2023; 28:100495. [PMID: 38406798 PMCID: PMC10883072 DOI: 10.1016/j.cobme.2023.100495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Cancer continues to affect underserved populations disproportionately. Novel optical imaging technologies, which can provide rapid, non-invasive, and accurate cancer detection at the point of care, have great potential to improve global cancer care. This article reviews the recent technical innovations and clinical translation of low-cost optical imaging technologies, highlighting the advances in both hardware and software, especially the integration of artificial intelligence, to improve in vivo cancer detection in low-resource settings. Additionally, this article provides an overview of existing challenges and future perspectives of adapting optical imaging technologies into clinical practice, which can potentially contribute to novel insights and programs that effectively improve cancer detection in low-resource settings.
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Affiliation(s)
- Huayu Hou
- Department of Bioengineering, Rice University, Houston, TX 77005, USA
| | - Ruchika Mitbander
- Department of Bioengineering, Rice University, Houston, TX 77005, USA
| | - Yubo Tang
- Department of Bioengineering, Rice University, Houston, TX 77005, USA
| | - Ahad Azimuddin
- School of Medicine, Texas A&M University, Houston, TX 77030, USA
| | - Jennifer Carns
- Department of Bioengineering, Rice University, Houston, TX 77005, USA
| | - Richard A Schwarz
- Department of Bioengineering, Rice University, Houston, TX 77005, USA
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He Q, Li W, Shi Y, Yu Y, Geng W, Sun Z, Wang RK. SpeCamX: mobile app that turns unmodified smartphones into multispectral imagers. BIOMEDICAL OPTICS EXPRESS 2023; 14:4929-4946. [PMID: 37791269 PMCID: PMC10545193 DOI: 10.1364/boe.497602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 08/13/2023] [Accepted: 08/14/2023] [Indexed: 10/05/2023]
Abstract
We present the development of SpeCamX, a mobile application that enables an unmodified smartphone into a multispectral imager. Multispectral imaging provides detailed spectral information about objects or scenes, but its accessibility has been limited due to its specialized requirements for the device. SpeCamX overcomes this limitation by utilizing the RGB photographs captured by smartphones and converting them into multispectral images spanning a range of 420 to 680 nm without a need for internal modifications or external attachments. The app also includes plugin functions for extracting medical information from the resulting multispectral data cube. In a clinical study, SpeCamX was used to implement an augmented smartphone bilirubinometer, predicting blood bilirubin levels (BBL) with superior performance in accuracy, efficiency and stability compared to default smartphone cameras. This innovative technology democratizes multispectral imaging, making it accessible to a wider audience and opening new possibilities for both medical and non-medical applications.
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Affiliation(s)
- Qinghua He
- Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Science, Changchun, Jilin 130033, China
- Department of Bioengineering, University of Washington, Seattle, Washington 98105, USA
| | - Wanyu Li
- Department of Hepatobiliary and pancreatic Medicine, The first Hospital of Jilin University NO.71 Xinmin Street, Changchun, Jilin 130021, China
| | - Yaping Shi
- Department of Bioengineering, University of Washington, Seattle, Washington 98105, USA
| | - Yi Yu
- Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Science, Changchun, Jilin 130033, China
| | - Wenqian Geng
- Department of Hepatobiliary and pancreatic Medicine, The first Hospital of Jilin University NO.71 Xinmin Street, Changchun, Jilin 130021, China
| | - Zhiyuan Sun
- Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Science, Changchun, Jilin 130033, China
| | - Ruikang K Wang
- Department of Bioengineering, University of Washington, Seattle, Washington 98105, USA
- Department of Ophthalmology, University of Washington, Seattle, Washington 98109, USA
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Ma L, Huang X, Qiu Y, He Y. Analysis of facial redness by comparing VISIA and YLGTD. Skin Res Technol 2023; 29:e13356. [PMID: 37522504 PMCID: PMC10280608 DOI: 10.1111/srt.13356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 05/08/2023] [Indexed: 08/01/2023]
Abstract
BACKGROUND Erythema, characterized by redness of the skin, is a common symptom in various facial skin conditions. Recent advancements in image processing and analysis techniques have led to the development of methods for analyzing and assessing skin texture. This study aimed to investigate the correlation between the parameters of "You Look Good Today" (YLGTD) and VISIA in the detection and assessment of facial redness. MATERIALS AND METHODS Thirty female subjects participated in this experiment, undergoing assessments using both YLGTD and VISIA. The subjects were evaluated for facial redness, and the feature count results within the red zone were measured by VISIA. YLGTD analyzed the number and percentage of red zone pixels. The assessments were conducted between [specific dates] in [location]. RESULTS The results demonstrated a significant positive correlation between the feature count results within the red zone measured by VISIA and the number of red zone pixels. Similarly, YLGTD exhibited a significant positive correlation with the number and percentage of red zone pixels. CONCLUSION In conclusion, our findings suggest a correlation between YLGTD and VISIA in the measurement of facial erythema. YLGTD can serve as a portable device for primary screening assessments, offering a convenient and reliable method to evaluate facial redness. This research contributes to the development of non-invasive techniques for assessing and monitoring facial skin conditions, providing valuable insights for dermatological diagnosis and cosmetic testing.
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Affiliation(s)
- Lei Ma
- School of Information Science and TechnologyNantong UniversityNantongChina
| | - Xin Huang
- School of Information Science and TechnologyNantong UniversityNantongChina
| | - Yuanyuan Qiu
- Jiangsu ZiXia BioTechnology Co, Ltd.ShanghaiChina
| | - Yu He
- Boyu Science Tech Co. Ltd.ShanghaiChina
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Malone JD, Hussain I, Bowden AK. SmartOCT: smartphone-integrated optical coherence tomography. BIOMEDICAL OPTICS EXPRESS 2023; 14:3138-3151. [PMID: 37497502 PMCID: PMC10368059 DOI: 10.1364/boe.492439] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/22/2023] [Accepted: 05/23/2023] [Indexed: 07/28/2023]
Abstract
Smartphone devices have seen unprecedented technical innovation in computational power and optical imaging capabilities, making them potentially invaluable tools in scientific imaging applications. The smartphone's compact form-factor and broad accessibility has motivated researchers to develop smartphone-integrated imaging systems for a wide array of applications. Optical coherence tomography (OCT) is one such technique that could benefit from smartphone-integration. Here, we demonstrate smartOCT, a smartphone-integrated OCT system that leverages built-in components of a smartphone for detection, processing and display of OCT data. SmartOCT uses a broadband visible-light source and line-field OCT design that enables snapshot 2D cross-sectional imaging. Furthermore, we describe methods for processing smartphone data acquired in a RAW data format for scientific applications that improves the quality of OCT images. The results presented here demonstrate the potential of smartphone-integrated OCT systems for low-resource environments.
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Affiliation(s)
- Joseph D. Malone
- Vanderbilt University, Dept. of Biomedical Engineering, Nashville, TN
37235, USA
- Vanderbilt University, Vanderbilt Biophotonics Center, Nashville, TN
37235, USA
| | - Iftak Hussain
- Vanderbilt University, Dept. of Biomedical Engineering, Nashville, TN
37235, USA
- Vanderbilt University, Vanderbilt Biophotonics Center, Nashville, TN
37235, USA
| | - Audrey K. Bowden
- Vanderbilt University, Dept. of Biomedical Engineering, Nashville, TN
37235, USA
- Vanderbilt University, Vanderbilt Biophotonics Center, Nashville, TN
37235, USA
- Vanderbilt University, Dept. of Electrical and Computer Engineering,
Nashville, TN 37235, USA
- Vanderbilt University, Vanderbilt Institute of Global Health, Nashville,
TN 37235, USA
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Wawrzyk-Bochenek I, Rahnama M, Stachura M, Wilczyński S, Wawrzyk A. Evaluation of the Reduction of Skin Hyperpigmentation Changes under the Influence of a Preparation Containing Kojic Acid Using Hyperspectral Imaging—Preliminary Study. J Clin Med 2023; 12:jcm12072710. [PMID: 37048793 PMCID: PMC10094916 DOI: 10.3390/jcm12072710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/22/2023] [Accepted: 04/03/2023] [Indexed: 04/08/2023] Open
Abstract
Aim: The aim of this study was to demonstrate the effects of using a preparation containing kojic acid on skin hyperpigmentation using hyperspectral imaging, which enables a quantitative assessment of the effect of the preparation used on the reduction of skin discoloration. Materials and methods: Preliminary studies were carried out on 12 patients with post-acne skin. A hyperspectral camera with a spectral range of 400–1000 nm was used to image skin hyperpigmentation before and after the application of 3% kojic acid. Hyperspectral profiles were analyzed, and image analysis and processing methods were applied. Results: Studies performed using a hyperspectral camera have shown that kojic acid reduces skin discoloration by increasing skin brightness in 75% of patients tested, reducing skin contrast in approximately 83% and increasing skin homogeneity in approximately 67% of patients.
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Affiliation(s)
- Iga Wawrzyk-Bochenek
- Department of Basic Biomedical Science, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia, Kasztanowa 3, 41-205 Sosnowiec, Poland
| | - Mansur Rahnama
- Chair and Department of Oral Surgery, Medical University of Lublin, Chodźki 6, 20-093 Lublin, Poland
| | - Martyna Stachura
- Department of Basic Biomedical Science, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia, Kasztanowa 3, 41-205 Sosnowiec, Poland
| | - Sławomir Wilczyński
- Department of Basic Biomedical Science, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia, Kasztanowa 3, 41-205 Sosnowiec, Poland
| | - Anna Wawrzyk
- Department of Basic Biomedical Science, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia, Kasztanowa 3, 41-205 Sosnowiec, Poland
- Silesian Park of Medical Technology Kardio-Med Silesia in Zabrze, M. Curie Skłodowskiej 10C, 41-800 Zabrze, Poland
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Ji Y, Park SM, Kwon S, Leem JW, Nair VV, Tong Y, Kim YL. mHealth hyperspectral learning for instantaneous spatiospectral imaging of hemodynamics. PNAS NEXUS 2023; 2:pgad111. [PMID: 37113981 PMCID: PMC10129064 DOI: 10.1093/pnasnexus/pgad111] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 03/23/2023] [Indexed: 04/29/2023]
Abstract
Hyperspectral imaging acquires data in both the spatial and frequency domains to offer abundant physical or biological information. However, conventional hyperspectral imaging has intrinsic limitations of bulky instruments, slow data acquisition rate, and spatiospectral trade-off. Here we introduce hyperspectral learning for snapshot hyperspectral imaging in which sampled hyperspectral data in a small subarea are incorporated into a learning algorithm to recover the hypercube. Hyperspectral learning exploits the idea that a photograph is more than merely a picture and contains detailed spectral information. A small sampling of hyperspectral data enables spectrally informed learning to recover a hypercube from a red-green-blue (RGB) image without complete hyperspectral measurements. Hyperspectral learning is capable of recovering full spectroscopic resolution in the hypercube, comparable to high spectral resolutions of scientific spectrometers. Hyperspectral learning also enables ultrafast dynamic imaging, leveraging ultraslow video recording in an off-the-shelf smartphone, given that a video comprises a time series of multiple RGB images. To demonstrate its versatility, an experimental model of vascular development is used to extract hemodynamic parameters via statistical and deep learning approaches. Subsequently, the hemodynamics of peripheral microcirculation is assessed at an ultrafast temporal resolution up to a millisecond, using a conventional smartphone camera. This spectrally informed learning method is analogous to compressed sensing; however, it further allows for reliable hypercube recovery and key feature extractions with a transparent learning algorithm. This learning-powered snapshot hyperspectral imaging method yields high spectral and temporal resolutions and eliminates the spatiospectral trade-off, offering simple hardware requirements and potential applications of various machine learning techniques.
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Affiliation(s)
- Yuhyun Ji
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Sang Mok Park
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Semin Kwon
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Jung Woo Leem
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
| | | | - Yunjie Tong
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Young L Kim
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
- Purdue Institute for Cancer Research, Purdue University, West Lafayette, IN 47906, USA
- Regenstrief Center for Healthcare Engineering, Purdue University, West Lafayette, IN 47907, USA
- Purdue Quantum Science and Engineering Institute, Purdue University, West Lafayette, IN 47907, USA
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Tran MH, Fei B. Compact and ultracompact spectral imagers: technology and applications in biomedical imaging. JOURNAL OF BIOMEDICAL OPTICS 2023; 28:040901. [PMID: 37035031 PMCID: PMC10075274 DOI: 10.1117/1.jbo.28.4.040901] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 02/27/2023] [Indexed: 05/18/2023]
Abstract
Significance Spectral imaging, which includes hyperspectral and multispectral imaging, can provide images in numerous wavelength bands within and beyond the visible light spectrum. Emerging technologies that enable compact, portable spectral imaging cameras can facilitate new applications in biomedical imaging. Aim With this review paper, researchers will (1) understand the technological trends of upcoming spectral cameras, (2) understand new specific applications that portable spectral imaging unlocked, and (3) evaluate proper spectral imaging systems for their specific applications. Approach We performed a comprehensive literature review in three databases (Scopus, PubMed, and Web of Science). We included only fully realized systems with definable dimensions. To best accommodate many different definitions of "compact," we included a table of dimensions and weights for systems that met our definition. Results There is a wide variety of contributions from industry, academic, and hobbyist spaces. A variety of new engineering approaches, such as Fabry-Perot interferometers, spectrally resolved detector array (mosaic array), microelectro-mechanical systems, 3D printing, light-emitting diodes, and smartphones, were used in the construction of compact spectral imaging cameras. In bioimaging applications, these compact devices were used for in vivo and ex vivo diagnosis and surgical settings. Conclusions Compact and ultracompact spectral imagers are the future of spectral imaging systems. Researchers in the bioimaging fields are building systems that are low-cost, fast in acquisition time, and mobile enough to be handheld.
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Affiliation(s)
- Minh H. Tran
- University of Texas at Dallas, Department of Bioengineering, Richardson, Texas, United States
| | - Baowei Fei
- University of Texas at Dallas, Department of Bioengineering, Richardson, Texas, United States
- University of Texas Southwestern Medical Center, Department of Radiology, Dallas, Texas, United States
- University of Texas at Dallas, Center for Imaging and Surgical Innovation, Richardson, Texas, United States
- Address all correspondence to Baowei Fei,
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Ma L, Sherey J, Palsgrove D, Fei B. Conditional Generative Adversarial Network (cGAN) for Synthesis of Digital Histologic Images from Hyperspectral Images. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2023; 12471:124711D. [PMID: 38495871 PMCID: PMC10942653 DOI: 10.1117/12.2653715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Hyperspectral imaging (HSI) has been demonstrated in various digital pathology applications. However, the intrinsic high dimensionality of hyperspectral images makes it difficult for pathologists to visualize the information. The aim of this study is to develop a method to transform hyperspectral images of hemoxylin & eosin (H&E)-stained slides to natural-color RGB histologic images for easy visualization. Hyperspectral images were obtained at 40× magnification with an automated microscopic imaging system and downsampled by various factors to generate data equivalent to different magnifications. High-resolution digital histologic RGB images were cropped and registered to the corresponding hyperspectral images as the ground truth. A conditional generative adversarial network (cGAN) was trained to output natural color RGB images of the histological tissue samples. The generated synthetic RGBs have similar color and sharpness to real RGBs. Image classification was implemented using the real and synthetic RGBs, respectively, with a pretrained network. The classification of tumor and normal tissue using the HSI-synthesized RGBs yielded a comparable but slightly higher accuracy and AUC than the real RGBs. The proposed method can reduce the acquisition time of two imaging modalities while giving pathologists access to the high information density of HSI and the quality visualization of RGBs. This study demonstrated that HSI may provide a potentially better alternative to current RGB-based pathologic imaging and thus make HSI a viable tool for histopathological diagnosis.
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Affiliation(s)
- Ling Ma
- Center for Imaging and Surgical Innovation, University of Texas at Dallas, Richardson, TX
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX
| | - Jeremy Sherey
- Center for Imaging and Surgical Innovation, University of Texas at Dallas, Richardson, TX
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX
| | - Doreen Palsgrove
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX
| | - Baowei Fei
- Center for Imaging and Surgical Innovation, University of Texas at Dallas, Richardson, TX
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX
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Zheng Y, Lin Z, Ding W, Yi M, Guan C, Han D, Zhong J, Tan H, Wang X, Xiong H, Wang M, Zeng Y. Heart rate estimation from color video sequences with high SNR. OPTICS LETTERS 2023; 48:379-382. [PMID: 36638462 DOI: 10.1364/ol.476117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 12/01/2022] [Indexed: 06/17/2023]
Abstract
We propose an absorption intensity heartbeat modulation-averaged shifted histogram (AIHM-ASH) method for estimating human heart rate (HR) using color videos of lip image sequences. When heartbeat occurs, AIHM is generated. Based on the AIHM, HR signals can be demodulated by computing the instantaneous HR modulation depth that presents the relative red blood cell (RBC) concentration from the green channel image of the RGB color video. In addition, the ASH algorithm further suppresses the background tissue and vein signals, and increases the signal-to-noise ratio (SNR). The experimental results for flow phantoms, chicken embryos, and human lips validated the proposed method's optimal estimation conditions and effectiveness, where the accuracy and root mean square error (RMSE) were 99.23% and 0.8 bpm, respectively. The proposed HR estimation method has significant potential to advance health monitoring and disease prevention via conventional color video cameras installed in public places.
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13
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Zhong C, Liang G, Li P, Shi K, Li F, Zhou J, Xu D. Inflammatory response: The target for treating hyperpigmentation during the repair of a burn wound. Front Immunol 2023; 14:1009137. [PMID: 36817442 PMCID: PMC9929571 DOI: 10.3389/fimmu.2023.1009137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 01/04/2023] [Indexed: 02/04/2023] Open
Abstract
Hyperpigmentation is a common complication in patients with burn injuries during wound healing; however, the mechanisms underlying its occurrence and development remain unclear. Recently, postinflammatory hyperpigmentation (PIH) was found to result from overproduction of melanin. Local or systemic inflammatory responses are often observed in patients who develop hyperpigmentation. However, we lack studies on the relationship between PIH and burn injury. Therefore, we comprehensively reviewed the existing literature on the melanogenesis of the skin, inflammatory mechanisms in pigmentation, and local or systemic alteration in inflammatory cytokines in patients suffering from burn trauma to elucidate the relationship between PIH and burn injury. We believe that this review will guide further research on regulating melanin production in the burn management process.
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Affiliation(s)
- Chi Zhong
- Department of Plastic Surgery, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Geao Liang
- Department of Plastic Surgery, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Peiting Li
- Department of Plastic Surgery, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Ke Shi
- Department of Plastic Surgery, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Fuyin Li
- Department of Plastic Surgery, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Jianda Zhou
- Department of Plastic Surgery, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Dan Xu
- Department of Plastic Surgery, The Third Xiangya Hospital, Central South University, Changsha, China
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14
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Gong Z, Yu C, Guo D, Ding Z, Li P. Three-dimensional optical coherence digital-null deformography of multi-refractive-surface optics with nanometer sensitivity. OPTICS EXPRESS 2022; 30:42069-42085. [PMID: 36366668 DOI: 10.1364/oe.472763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 10/22/2022] [Indexed: 06/16/2023]
Abstract
Knowledge of the lens deformation during the reliability test is critical for lens design and fabrication. Refractive surface distorts the optical path of probing light, and poses a great challenge to measuring the test-induced nanoscale changes of all refractive lens surfaces simultaneously. In this work, we present an optical coherence digital-null deformography (ODD). A digital null, i.e., the interference signals (including intensity and phase) of the backscattered probing light from each lens surface, was recorded prior to the test with a phase-sensitive optical coherence tomography (OCT). Then the post-test lens was physically aligned to the digital null by actuating a hexapod iteratively with a digital null alignment (DNA) method, so that the refractive distortion was matched. Finally, the changes between the aligned lens and its digital null were measured with an intensity centroid shift (ICS) at micron scale and a joint wavenumber (k)-depth (z) domain phase shift (kz-PhS) at nanoscale. We demonstrate that the proposed kz-PhS has a sensitivity of 4.15 nm and a range of 5 µm without phase wrapping; and the sensitivities of DNA are z translation 0.04 µm, x/y translation 0.24 µm, tilt 0.0003°, and rotation 0.03°. A lens drop test was performed with ODD. Circumventing refractive distortion by the null measurement, ODD can visualize the test-induced changes of all refractive surfaces non-destructively and simultaneously, and it will greatly facilitate lens design and fabrication.
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15
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Wen YC, Wen S, Hsu L, Chi S. Irradiance Independent Spectrum Reconstruction from Camera Signals Using the Interpolation Method. SENSORS (BASEL, SWITZERLAND) 2022; 22:s22218498. [PMID: 36366197 PMCID: PMC9656597 DOI: 10.3390/s22218498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 10/28/2022] [Accepted: 11/01/2022] [Indexed: 05/25/2023]
Abstract
The spectrum of light captured by a camera can be reconstructed using the interpolation method. The reconstructed spectrum is a linear combination of the reference spectra, where the weighting coefficients are calculated from the signals of the pixel and the reference samples by interpolation. This method is known as the look-up table (LUT) method. It is irradiance-dependent due to the dependence of the reconstructed spectrum shape on the sample irradiance. Since the irradiance can vary in field applications, an irradiance-independent LUT (II-LUT) method is required to recover spectral reflectance. This paper proposes an II-LUT method to interpolate the spectrum in the normalized signal space. Munsell color chips irradiated with D65 were used as samples. Example cameras are a tricolor camera and a quadcolor camera. Results show that the proposed method can achieve the irradiance independent spectrum reconstruction and computation time saving at the expense of the recovered spectral reflectance error. Considering that the irradiance variation will introduce additional errors, the actual mean error using the II-LUT method might be smaller than that of the ID-LUT method. It is also shown that the proposed method outperformed the weighted principal component analysis method in both accuracy and computation speed.
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Affiliation(s)
- Yu-Che Wen
- Department of Electrophysics, National Yang Ming Chiao Tung University, No. 1001 University Road, Hsinchu 30010, Taiwan
| | - Senfar Wen
- Department of Electrical Engineering, Yuan Ze University, No. 135 Yuan-Tung Road, Taoyuan 32003, Taiwan
| | - Long Hsu
- Department of Electrophysics, National Yang Ming Chiao Tung University, No. 1001 University Road, Hsinchu 30010, Taiwan
| | - Sien Chi
- Department of Photonics, National Yang Ming Chiao Tung University, No. 1001 University Road, Hsinchu 30010, Taiwan
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16
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Nishidate I, Yasui R, Nagao N, Suzuki H, Takara Y, Ohashi K, Ando F, Noro N, Kokubo Y. RGB camera-based simultaneous measurements of percutaneous arterial oxygen saturation, tissue oxygen saturation, pulse rate, and respiratory rate. Front Physiol 2022; 13:933397. [PMID: 36200058 PMCID: PMC9527277 DOI: 10.3389/fphys.2022.933397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 08/25/2022] [Indexed: 11/24/2022] Open
Abstract
We propose a method to perform simultaneous measurements of percutaneous arterial oxygen saturation (SpO2), tissue oxygen saturation (StO2), pulse rate (PR), and respiratory rate (RR) in real-time, using a digital red–green–blue (RGB) camera. Concentrations of oxygenated hemoglobin (CHbO), deoxygenated hemoglobin (CHbR), total hemoglobin (CHbT), and StO2 were estimated from videos of the human face using a method based on a tissue-like light transport model of the skin. The photoplethysmogram (PPG) signals are extracted from the temporal fluctuations in CHbO, CHbR, and CHbT using a finite impulse response (FIR) filter (low and high cut-off frequencies of 0.7 and 3 Hz, respectively). The PR is calculated from the PPG signal for CHbT. The ratio of pulse wave amplitude for CHbO and that for CHbR are associated with the reference value of SpO2 measured by a commercially available pulse oximeter, which provides an empirical formula to estimate SpO2 from videos. The respiration-dependent oscillation in CHbT was extracted from another FIR filter (low and high cut-off frequencies of 0.05 and 0.5 Hz, respectively) and used to calculate the RR. In vivo experiments with human volunteers while varying the fraction of inspired oxygen were performed to evaluate the comparability of the proposed method with commercially available devices. The Bland–Altman analysis showed that the mean bias for PR, RR, SpO2, and StO2 were -1.4 (bpm), -1.2(rpm), 0.5 (%), and -3.0 (%), respectively. The precisions for PR, RR, Sp O2, and StO2 were ±3.1 (bpm), ±3.5 (rpm), ±4.3 (%), and ±4.8 (%), respectively. The resulting precision and RMSE for StO2 were pretty close to the clinical accuracy requirement. The accuracy of the RR is considered a little less accurate than clinical requirements. This is the first demonstration of a low-cost RGB camera-based method for contactless simultaneous measurements of the heart rate, percutaneous arterial oxygen saturation, and tissue oxygen saturation in real-time.
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Affiliation(s)
- Izumi Nishidate
- Tokyo University of Agriculture and Technology, Graduate School of Bio-Applications and Systems Engineering, Tokyo, Japan
- *Correspondence: Izumi Nishidate,
| | - Riku Yasui
- Tokyo University of Agriculture and Technology, Graduate School of Bio-Applications and Systems Engineering, Tokyo, Japan
| | - Nodoka Nagao
- Tokyo University of Agriculture and Technology, Graduate School of Bio-Applications and Systems Engineering, Tokyo, Japan
| | - Haruta Suzuki
- Tokyo University of Agriculture and Technology, Graduate School of Bio-Applications and Systems Engineering, Tokyo, Japan
| | | | | | | | | | - Yasuaki Kokubo
- Department of Neurosurgery, Faculty of Medicine, Yamagata University, Yamagata, Japan
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17
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Taylor-Williams M, Spicer G, Bale G, Bohndiek SE. Noninvasive hemoglobin sensing and imaging: optical tools for disease diagnosis. JOURNAL OF BIOMEDICAL OPTICS 2022; 27:JBO-220074VR. [PMID: 35922891 PMCID: PMC9346606 DOI: 10.1117/1.jbo.27.8.080901] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 06/27/2022] [Indexed: 05/08/2023]
Abstract
SIGNIFICANCE Measurement and imaging of hemoglobin oxygenation are used extensively in the detection and diagnosis of disease; however, the applied instruments vary widely in their depth of imaging, spatiotemporal resolution, sensitivity, accuracy, complexity, physical size, and cost. The wide variation in available instrumentation can make it challenging for end users to select the appropriate tools for their application and to understand the relative limitations of different methods. AIM We aim to provide a systematic overview of the field of hemoglobin imaging and sensing. APPROACH We reviewed the sensing and imaging methods used to analyze hemoglobin oxygenation, including pulse oximetry, spectral reflectance imaging, diffuse optical imaging, spectroscopic optical coherence tomography, photoacoustic imaging, and diffuse correlation spectroscopy. RESULTS We compared and contrasted the ability of different methods to determine hemoglobin biomarkers such as oxygenation while considering factors that influence their practical application. CONCLUSIONS We highlight key limitations in the current state-of-the-art and make suggestions for routes to advance the clinical use and interpretation of hemoglobin oxygenation information.
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Affiliation(s)
- Michaela Taylor-Williams
- University of Cambridge, Department of Physics, Cavendish Laboratory, Cambridge, United Kingdom, United Kingdom
- University of Cambridge, Cancer Research UK Cambridge Institute, Cambridge, United Kingdom, United Kingdom
| | - Graham Spicer
- University of Cambridge, Department of Physics, Cavendish Laboratory, Cambridge, United Kingdom, United Kingdom
- University of Cambridge, Cancer Research UK Cambridge Institute, Cambridge, United Kingdom, United Kingdom
| | - Gemma Bale
- University of Cambridge, Department of Physics, Cavendish Laboratory, Cambridge, United Kingdom, United Kingdom
- University of Cambridge, Electrical Division, Department of Engineering, Cambridge, United Kingdom, United Kingdom
| | - Sarah E Bohndiek
- University of Cambridge, Department of Physics, Cavendish Laboratory, Cambridge, United Kingdom, United Kingdom
- University of Cambridge, Cancer Research UK Cambridge Institute, Cambridge, United Kingdom, United Kingdom
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18
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He Q, Wang RK. Imaging-photoplethysmography-guided optical microangiography. OPTICS LETTERS 2022; 47:2302-2305. [PMID: 35486784 DOI: 10.1364/ol.452326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 04/04/2022] [Indexed: 06/14/2023]
Abstract
We report a method to image facial cutaneous microvascular perfusion using wide-field imaging photoplethysmography (iPPG) and handheld swept-source optical coherence tomography (OCT). The iPPG system employs a 16-bit-depth camera to provide a 2D wide-field blood pulsation map that is then used as a positioning guidance for OCT imaging of cutaneous microvasculature. We show the results from iPPG and OCT to demonstrate the ability of guided imaging of cutaneous microvasculature, which is potentially useful for the assessment of skin conditions in dermatology and cosmetology.
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19
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Tominaga S, Nishi S, Ohtera R, Sakai H. Improved method for spectral reflectance estimation and application to mobile phone cameras. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2022; 39:494-508. [PMID: 35297433 DOI: 10.1364/josaa.449347] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 01/21/2022] [Indexed: 06/14/2023]
Abstract
We propose an improved method for estimating surface-spectral reflectance from the image data acquired by an RGB digital camera. We suppose a multispectral image acquisition system in the visible range, where a camera captures multiple images for the scene of an object under multiple light sources. First, the observed image data are described using the camera spectral sensitivities, the surface-spectral reflectance, the illuminant spectral power distributions, an additive noise term, and a gain parameter. Then, the optimal reflectance estimate is determined to minimize the mean-square error between the estimate and the original surface-spectral reflectance. We attempt to further improve the estimation accuracy and develop a novel linear estimator in a more general form than the Wiener estimator. Furthermore, we calibrate the imaging system using a reference standard sample. Finally, experiments are performed to validate the proposed method for estimating the surface-spectral reflectance using different mobile phone cameras.
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20
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Hammer A, Scherpf M, Schmidt M, Ernst H, Malberg H, Matschke K, Dragu A, Martin J, Bota O. Camera-based assessment of cutaneous perfusion strength in a clinical setting. Physiol Meas 2022; 43. [PMID: 35168227 DOI: 10.1088/1361-6579/ac557d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 02/15/2022] [Indexed: 01/03/2023]
Abstract
Objective. After skin flap transplants, perfusion strength monitoring is essential for the early detection of tissue perfusion disorders and thus to ensure the survival of skin flaps. Camera-based photoplethysmography (cbPPG) is a non-contact measurement method, using video cameras and ambient light, which provides spatially resolved information about tissue perfusion. It has not been researched yet whether the measurement depth of cbPPG, which is limited by the penetration depth of ambient light, is sufficient to reach pulsatile vessels and thus to measure the perfusion strength in regions that are relevant for skin flap transplants.Approach. We applied constant negative pressure (compared to ambient pressure) to the anterior thighs of 40 healthy subjects. Seven measurements (two before and five up to 90 minutes after the intervention) were acquired using an RGB video camera and photospectrometry simultaneously. We investigated the performance of different algorithmic approaches for perfusion strength assessment, including the signal-to-noise ratio (SNR), its logarithmic components logS and logN, amplitude maps, and the amplitude height of alternating and direct signal components.Main results. We found strong correlations of up tor=0.694 (p<0.001) between photospectrometric measurements and all cbPPG parameters except SNR when using the green color channel. The transfer of cbPPG signals to POS, CHROM, and O3C did not lead to systematic improvements. However, for direct signal components, the transformation to O3C led to correlations of up tor=0.744 (p<0.001) with photospectrometric measurements.Significance. Our results indicate that a camera-based perfusion strength assessment in tissue with deep-seated pulsatile vessels is possible.
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Affiliation(s)
- Alexander Hammer
- Institute of Biomedical Engineering, TU Dresden, Fetscherstr. 29, Dresden, 01307, GERMANY
| | - Matthieu Scherpf
- Institute of Biomedical Engineering, TU Dresden, Fetscherstr. 29, Dresden, 01307, GERMANY
| | - Martin Schmidt
- Institute of Biomedical Engineering, TU Dresden, Fetscherstr. 29, Dresden, 01307, GERMANY
| | - Hannes Ernst
- Institute of Biomedical Engineering, TU Dresden, Fetscherstr. 29, Dresden, 01307, GERMANY
| | - Hagen Malberg
- Institute of Biomedical Engineering, TU Dresden, Fetscherstr. 29, Dresden, 01307, GERMANY
| | - Klaus Matschke
- Department of Cardiac Surgery, University Heart Center Dresden, TU Dresden, Fetscherstr. 76, Dresden, 01307, GERMANY
| | - Adrian Dragu
- University Center for Orthopedics, Trauma and Plastic Surgery, Faculty of Medicine Carl Gustav Carus, TU Dresden, Fetscherstr. 74, Dresden, 01307, GERMANY
| | - Judy Martin
- University Center for Orthopedics, Trauma and Plastic Surgery, Faculty of Medicine Carl Gustav Carus, TU Dresden, Fetscherstr. 74, Dresden, 01037, GERMANY
| | - Olimpiu Bota
- University Center for Orthopedics, Trauma and Plastic Surgery, Faculty of Medicine Carl Gustav Carus, TU Dresden, Fetscherstr. 74, Dresden, 01307, GERMANY
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21
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Kuzmina I, Oshina I, Dambite L, Lukinsone V, Maslobojeva A, Berzina A, Spigulis J. Skin chromophore mapping by smartphone RGB camera under spectral band and spectral line illumination. JOURNAL OF BIOMEDICAL OPTICS 2022; 27:JBO-210361GR. [PMID: 35191236 PMCID: PMC8860175 DOI: 10.1117/1.jbo.27.2.026004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 01/26/2022] [Indexed: 05/05/2023]
Abstract
SIGNIFICANCE Multispectral imaging enables mapping of chromophore content changes in skin neoplasms, which helps to diagnose a pathology. Different types of light sources can be used for the imaging. Design of laser-based illuminators is more complicated and, consequently, they are more expensive than LED-based illuminators. On the other hand, spectral line illumination has the advantage of less complicated calculations, since only the discrete maximum wavelengths need to be considered. Spectral band and spectral line approaches for multispectral skin diagnostics have not been compared so far. This can help to evaluate the accuracy and effectiveness of both approaches. AIM To compare two specific illumination modalities-spectral band and spectral line illumination-from the point of performance for mapping of in vivo skin chromophores. APPROACH Three spectral images of the same skin malformations were captured by a smartphone RGB camera with two different add-on illuminators comprising LED emitters and laser emitters, respectively. Five types of benign skin neoplasms were included in our study. Concentrations of skin melanin, oxy- and deoxy-hemoglobin at image pixel groups were calculated using the Beer-Lambert law. RESULTS Skin chromophore maps and statistical analysis of mean concentrations' changes in the neoplasms compared to the surrounding skin are presented and discussed. The data of the laser emitters led to significantly higher (∼10 times) increase of the oxy-hemoglobin values in vascular neoplasms and much lower deoxy-hemoglobin values, if compared to the data obtained by the LED emitters. CONCLUSIONS Analysis of the obtained chromophore distribution maps and concentration variations in neoplasms led to conclusion that the spectral line illumination approach is more appropriate for this application. Considering only the peak wavelengths of illumination spectral bands leads to essentially different results if compared to those obtained by spectral line illumination and may cause misinterpretations in the clinical assessment of skin neoplasms.
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Affiliation(s)
- Ilona Kuzmina
- University of Latvia, Institute of Atomic Physics and Spectroscopy, Biophotonics Laboratory, Riga, Latvia
- Address all correspondence to Ilona Kuzmina,
| | - Ilze Oshina
- University of Latvia, Institute of Atomic Physics and Spectroscopy, Biophotonics Laboratory, Riga, Latvia
| | - Laura Dambite
- University of Latvia, Institute of Atomic Physics and Spectroscopy, Biophotonics Laboratory, Riga, Latvia
| | - Vanesa Lukinsone
- University of Latvia, Institute of Atomic Physics and Spectroscopy, Biophotonics Laboratory, Riga, Latvia
| | - Anna Maslobojeva
- University of Latvia, Institute of Atomic Physics and Spectroscopy, Biophotonics Laboratory, Riga, Latvia
| | - Anna Berzina
- University of Latvia, Institute of Atomic Physics and Spectroscopy, Biophotonics Laboratory, Riga, Latvia
- The Clinic of Laser Plastics, Riga, Latvia
| | - Janis Spigulis
- University of Latvia, Institute of Atomic Physics and Spectroscopy, Biophotonics Laboratory, Riga, Latvia
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22
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Abstract
AbstractMeasuring morphological and biochemical features of tissue is crucial for disease diagnosis and surgical guidance, providing clinically significant information related to pathophysiology. Hyperspectral imaging (HSI) techniques obtain both spatial and spectral features of tissue without labeling molecules such as fluorescent dyes, which provides rich information for improved disease diagnosis and treatment. Recent advances in HSI systems have demonstrated its potential for clinical applications, especially in disease diagnosis and image-guided surgery. This review summarizes the basic principle of HSI and optical systems, deep-learning-based image analysis, and clinical applications of HSI to provide insight into this rapidly growing field of research. In addition, the challenges facing the clinical implementation of HSI techniques are discussed.
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23
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Ryu J, Hong S, Liang S, Pak S, Chen Q, Yan S. A New Framework for Robust Heart Rate Measurement Based on the Head Motion State Estimation. IEEE J Biomed Health Inform 2021; 25:3428-3437. [PMID: 34038374 DOI: 10.1109/jbhi.2021.3083917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
It is of great significance in managing human health, preventing and curing diseases such as heart disease to measure and monitor the physiological parameters accurately and robustly. However, imaging photoplethysmography (iPPG) can be easily affected by the ambient illumination variations or the subject's motions. In this paper, therefore, a novel framework of heart rate (HR) measurement robust to both illumination and motion artefacts is proposed, which combines the projection-plane-switching-based iPPG method (2PS) with the singular spectrum analysis (SSA). Based on the estimation of the head motion state, one reasonable projection plane is firstly determined, the temporally normalized red-green-blue signals are projected onto the plane and a pulse signal is obtained by alpha-tuning. After that, singular spectrum analysis (SSA) is applied to the obtained pulse signal and the normalized B-channel signal of the facial region of interest (ROI) to remove the artefacts remained in the pulse signal. For the self-collected database and the public PURE database, Bland-Altman plots show that the proposed 2PS-SSA has better agreement than the five compared methods, where the mean biases are 0.59 beat per minute (bpm) and 0.034 bpm, with 95% limits from -2.59 bpm to 3.78 bpm and from -1.97 bpm to 2.04 bpm, respectively.
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24
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Stuart MB, McGonigle AJS, Davies M, Hobbs MJ, Boone NA, Stanger LR, Zhu C, Pering TD, Willmott JR. Low-Cost Hyperspectral Imaging with A Smartphone. J Imaging 2021; 7:jimaging7080136. [PMID: 34460772 PMCID: PMC8404918 DOI: 10.3390/jimaging7080136] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/28/2021] [Accepted: 08/02/2021] [Indexed: 11/16/2022] Open
Abstract
Recent advances in smartphone technologies have opened the door to the development of accessible, highly portable sensing tools capable of accurate and reliable data collection in a range of environmental settings. In this article, we introduce a low-cost smartphone-based hyperspectral imaging system that can convert a standard smartphone camera into a visible wavelength hyperspectral sensor for ca. £100. To the best of our knowledge, this represents the first smartphone capable of hyperspectral data collection without the need for extensive post processing. The Hyperspectral Smartphone’s abilities are tested in a variety of environmental applications and its capabilities directly compared to the laboratory-based analogue from our previous research, as well as the wider existing literature. The Hyperspectral Smartphone is capable of accurate, laboratory- and field-based hyperspectral data collection, demonstrating the significant promise of both this device and smartphone-based hyperspectral imaging as a whole.
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Affiliation(s)
- Mary B. Stuart
- Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S1 4DE, UK; (M.B.S.); (M.D.); (M.J.H.); (N.A.B.); (L.R.S.); (C.Z.)
| | - Andrew J. S. McGonigle
- Department of Geography, University of Sheffield, Sheffield S10 2TN, UK; (A.J.S.M.); (T.D.P.)
| | - Matthew Davies
- Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S1 4DE, UK; (M.B.S.); (M.D.); (M.J.H.); (N.A.B.); (L.R.S.); (C.Z.)
| | - Matthew J. Hobbs
- Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S1 4DE, UK; (M.B.S.); (M.D.); (M.J.H.); (N.A.B.); (L.R.S.); (C.Z.)
| | - Nicholas A. Boone
- Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S1 4DE, UK; (M.B.S.); (M.D.); (M.J.H.); (N.A.B.); (L.R.S.); (C.Z.)
| | - Leigh R. Stanger
- Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S1 4DE, UK; (M.B.S.); (M.D.); (M.J.H.); (N.A.B.); (L.R.S.); (C.Z.)
| | - Chengxi Zhu
- Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S1 4DE, UK; (M.B.S.); (M.D.); (M.J.H.); (N.A.B.); (L.R.S.); (C.Z.)
- Cambridge Advanced Imaging Centre, University of Cambridge, Cambridge CB2 3DY, UK
| | - Tom D. Pering
- Department of Geography, University of Sheffield, Sheffield S10 2TN, UK; (A.J.S.M.); (T.D.P.)
| | - Jon R. Willmott
- Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S1 4DE, UK; (M.B.S.); (M.D.); (M.J.H.); (N.A.B.); (L.R.S.); (C.Z.)
- Correspondence:
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25
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Restrepo L, Murillo J, Botina D, Zarzycki A, Garzón J, Franco R, Montano J, Calderon S, Torres-Madronero MC, Marzani F, Robledo SM, Galeano J. Diffuse Reflectance Parameters of Treated Leishmaniasis Cutaneous Ulcers and Association with Histopathologies in an Animal Model: A Proof of Concept. SLAS Technol 2021; 26:667-680. [PMID: 34292085 DOI: 10.1177/24726303211030292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cutaneous leishmaniasis (CL) is a parasitic disease that produces chronic skin ulcers. Although it has a worldwide presence, it is a neglected disease that still requires novel tools for its management. In order to study the use of optical tools in CL, this article presents a preliminary study of the correlation between CL histopathological and optical parameters. Optical parameters correspond to absorption and scattering coefficients obtained from diffuse reflectance spectra of treated CL in golden hamsters. Independently, histopathological data were collected from the same hamsters. As a result, after Spearman correlation and the Kruskal-Wallis test, inverse correlation was found between absorption/scattering optical parameters and inflammatory histopathological values, such as the scattering parameter related to the diameter of fibroblasts with the histopathological parameters of fibrosis, polymorphonuclear neutrophils, lymphocytes, plasmocytes, hyperplasia, and Leishmania, and the absorption parameter oxygen saturation showed a relation with the granulation tissue histopathological parameter. These correlations agree with the expected behavior of tissue composition during the healing process in CL. The results correspond to a proof of concept that shows that optical diffuse reflectance-based tools and methods could be considered as an alternative to assist in CL diagnosis and treatment follow-up.
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Affiliation(s)
- Lina Restrepo
- Instituto Tecnológico Metropolitano, Medellín, Colombia
| | - Javier Murillo
- Program for the Study and Control of Tropical Diseases-PECET, School of Medicine, University of Antioquia, Medellín, Colombia
| | - Deivid Botina
- Research group on Advance Materials and Energy MatyEr, Biomaterials and Electromedicine Laboratory, Instituto Tecnológico Metropolitano, Medellín, Colombia.,Laboratoire ImViA, Université Bourgogne Franche-Comté, Dijon Cedex, France
| | - Artur Zarzycki
- Research group on Advance Materials and Energy MatyEr, Biomaterials and Electromedicine Laboratory, Instituto Tecnológico Metropolitano, Medellín, Colombia
| | - Johnson Garzón
- Grupo de Óptica y Espectroscopía, Centro de Ciencia Básica, Universidad Pontificia Bolivariana, Medellín, Colombia
| | - Ricardo Franco
- Research group on Automatic, Electronic and Computational Science, MIRP Laboratory, Instituto Tecnológico Metropolitano, Medellín, Colombia
| | - Jaime Montano
- Program for the Study and Control of Tropical Diseases-PECET, School of Medicine, University of Antioquia, Medellín, Colombia
| | - Samuel Calderon
- Program for the Study and Control of Tropical Diseases-PECET, School of Medicine, University of Antioquia, Medellín, Colombia
| | - Maria C Torres-Madronero
- Research group on Automatic, Electronic and Computational Science, MIRP Laboratory, Instituto Tecnológico Metropolitano, Medellín, Colombia
| | - Franck Marzani
- Laboratoire ImViA, Université Bourgogne Franche-Comté, Dijon Cedex, France
| | - Sara M Robledo
- Program for the Study and Control of Tropical Diseases-PECET, School of Medicine, University of Antioquia, Medellín, Colombia
| | - July Galeano
- Research group on Advance Materials and Energy MatyEr, Biomaterials and Electromedicine Laboratory, Instituto Tecnológico Metropolitano, Medellín, Colombia
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Kern C, Speck U, Riesenberg R, Reble C, Khazaka G, Zieger M, Kaatz M, De Gregorio M, Fischer F. Mobile snapshot hyperspectral imaging device for skin evaluation using diffractive optical elements. Skin Res Technol 2021; 27:589-598. [PMID: 33511672 PMCID: PMC8359345 DOI: 10.1111/srt.12991] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 12/05/2020] [Indexed: 11/29/2022]
Abstract
OBJECTIVE A mobile handheld snapshot hyperspectral imaging device was developed and tested for in vivo skin evaluation using a new spectral imaging technology. METHODS The device is equipped with four different LED light sources (VIS, 810 nm, 850 nm, and 940 nm) for illumination. Based on a diffractive optical element (DOE) combined with a CMOS sensor chip, a snapshot hyperspectral imager is achieved for the application on human skin. The diffractive optical element (DOE) consists of a two-dimensional array of identically repeated diffractive microstructures. One hyperspectral image for all wavelength regions is taken within a few seconds. Complex recalculation of the VIS spectral distribution and image information from the received DOE image requires several minutes, depending on computing performance. A risk assessment on the irradiation sources shows no risk of harm due to the LED radiation. RESULTS Skin tone color patches experiments reproducibly deliver images and spectra of different skin tones. First in vivo use of the device identified pigmentation changes within the field of view. CONCLUSION We present a working mobile snapshot hyperspectral imaging tool based on diffractive optical elements. This device or future developments thereof can be used for broad skin evaluation in vivo.
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Affiliation(s)
| | - Uwe Speck
- Speck Sensor Systems GmbHJenaGermany
| | | | | | | | - Michael Zieger
- Center for Clinical StudiesSRH Wald‐Klinikum Gera GmbHGeraGermany
| | - Martin Kaatz
- Center for Clinical StudiesSRH Wald‐Klinikum Gera GmbHGeraGermany
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He Q, Sun Z, Li Y, Wang W, Wang RK. Spatiotemporal monitoring of changes in oxy/deoxy-hemoglobin concentration and blood pulsation on human skin using smartphone-enabled remote multispectral photoplethysmography. BIOMEDICAL OPTICS EXPRESS 2021; 12:2919-2937. [PMID: 34168907 PMCID: PMC8194624 DOI: 10.1364/boe.423160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/19/2021] [Accepted: 04/19/2021] [Indexed: 06/13/2023]
Abstract
We propose a smartphone-enabled remote multispectral photoplethysmography (SP-rmPPG) system and method to realize spatiotemporal monitoring of perfusion changes and pulsations of the oxyhemoglobin (HbO2) and deoxyhemoglobin (Hb) information of the effective blood volume within light interrogated skin tissue beds. The system is implemented on an unmodified smartphone utilizing its built-in camera and flashlight to acquire videos of the skin reflectance. The SP-rmPPG method converts the RGB video into multispectral cubes, upon which to decouple the dynamic changes in HbO2 and Hb information using a modified Beer-Lambert law and the selective wavelength bands of 500 nm and 650 nm. Blood pulsation amplitudes are then obtained by applying a window-based lock-in amplification on the derived spatiotemporal changes in HbO2 or Hb signals. To demonstrate the feasibility of proposed method, we conduct two experiments on the skin tissue beds that are conditioned by occlusive maneuver of supplying arteries: one using the popular blood cuff pressure maneuver on the upper arm, and another artificially inducing a transient ischemic condition on the facial skin tissue beds by finger pressing on the supplying external carotid artery. The cuff experiment shows that the measured dynamic information of HbO2 and Hb in the downstream agrees well with the parallel measurements of oxygenation saturation given by the standard pulse oximeter. We also observe the expected imbalance of spatiotemporal changes in the HbO2 and Hb between the right and left cheeks when the transient ischemic condition is induced in the one side of facial skin tissue beds. The results from the two experiments sufficiently demonstrate the feasibility of the proposed method to monitor the spatiotemporal changes in the skin hemodynamics, including blood oxygenation and pulsation amplitudes. Considering the ever-growing accessibility and affordability of the smartphone to the general public, the proposed strategy promises the early screening of vascular diseases and improving general public health particularly in rural areas with low resource settings.
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Affiliation(s)
- Qinghua He
- Department of Bioengineering, University of Washington, Seattle, WA 98105, USA
| | - Zhiyuan Sun
- Department of Bioengineering, University of Washington, Seattle, WA 98105, USA
| | - Yuandong Li
- Department of Bioengineering, University of Washington, Seattle, WA 98105, USA
| | - Wendy Wang
- Department of Bioengineering, University of Washington, Seattle, WA 98105, USA
| | - Ruikang K. Wang
- Department of Bioengineering, University of Washington, Seattle, WA 98105, USA
- Department of Ophthalmology, University of Washington, Seattle, WA98105, USA
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Hunt B, Ruiz AJ, Pogue BW. Smartphone-based imaging systems for medical applications: a critical review. JOURNAL OF BIOMEDICAL OPTICS 2021; 26:JBO-200421VR. [PMID: 33860648 PMCID: PMC8047775 DOI: 10.1117/1.jbo.26.4.040902] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 03/29/2021] [Indexed: 05/15/2023]
Abstract
SIGNIFICANCE Smartphones come with an enormous array of functionality and are being more widely utilized with specialized attachments in a range of healthcare applications. A review of key developments and uses, with an assessment of strengths/limitations in various clinical workflows, was completed. AIM Our review studies how smartphone-based imaging (SBI) systems are designed and tested for specialized applications in medicine and healthcare. An evaluation of current research studies is used to provide guidelines for improving the impact of these research advances. APPROACH First, the established and emerging smartphone capabilities that can be leveraged for biomedical imaging are detailed. Then, methods and materials for fabrication of optical, mechanical, and electrical interface components are summarized. Recent systems were categorized into four groups based on their intended application and clinical workflow: ex vivo diagnostic, in vivo diagnostic, monitoring, and treatment guidance. Lastly, strengths and limitations of current SBI systems within these various applications are discussed. RESULTS The native smartphone capabilities for biomedical imaging applications include cameras, touchscreens, networking, computation, 3D sensing, audio, and motion, in addition to commercial wearable peripheral devices. Through user-centered design of custom hardware and software interfaces, these capabilities have the potential to enable portable, easy-to-use, point-of-care biomedical imaging systems. However, due to barriers in programming of custom software and on-board image analysis pipelines, many research prototypes fail to achieve a prospective clinical evaluation as intended. Effective clinical use cases appear to be those in which handheld, noninvasive image guidance is needed and accommodated by the clinical workflow. Handheld systems for in vivo, multispectral, and quantitative fluorescence imaging are a promising development for diagnostic and treatment guidance applications. CONCLUSIONS A holistic assessment of SBI systems must include interpretation of their value for intended clinical settings and how their implementations enable better workflow. A set of six guidelines are proposed to evaluate appropriateness of smartphone utilization in terms of clinical context, completeness, compactness, connectivity, cost, and claims. Ongoing work should prioritize realistic clinical assessments with quantitative and qualitative comparison to non-smartphone systems to clearly demonstrate the value of smartphone-based systems. Improved hardware design to accommodate the rapidly changing smartphone ecosystem, creation of open-source image acquisition and analysis pipelines, and adoption of robust calibration techniques to address phone-to-phone variability are three high priority areas to move SBI research forward.
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Affiliation(s)
- Brady Hunt
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire, United States
- Address all correspondence to Brady Hunt,
| | - Alberto J. Ruiz
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire, United States
| | - Brian W. Pogue
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire, United States
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Ryu J, Hong S, Liang S, Pak S, Chen Q, Yan S. A measurement of illumination variation-resistant noncontact heart rate based on the combination of singular spectrum analysis and sub-band method. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2021; 200:105824. [PMID: 33168271 DOI: 10.1016/j.cmpb.2020.105824] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 10/28/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND AND OBJECTIVE The imaging photoplethysmography method is a non-contact and non-invasive measurement method that usually uses surrounding illumination as an illuminant, which can be easily influenced by the surrounding illumination variations. Thus, it has a practical value to develop an efficient method of heart rate measurement that can remove the interference of illumination variations robustly. METHOD We propose a novel framework of heart rate measurement that is robust to illumination variations by combining singular spectrum analysis and sub-band method. At first, we extract the blood volume pulse signal by applying the modified sub-band method to the raw facial RGB trace signals. Then the spectra for the interference of illumination variations are extracted from the raw signal obtained from facial regions of interest by using singular spectrum analysis. Finally, we estimate the more robust heart rate through comparison analysis between the spectra of the extracted blood volume pulse signal and the illumination variations. RESULTS We compared our method with several state-of-the-art methods through the analysis using the self-collected data and the UBFC-RPPG database. Bland-Altman plots and Pearson correlation coefficients pointed out that the proposed method could measure the heart rate more accurately than the state-of-the-art methods. For the self-collected data and the UBFC-RPPG database, Bland-Altman plots showed that proposed method caused better agreement with 95% limits from -4 bpm to 10 bpm and from -2 bpm to 4 bpm respectively than the other state-of-the-art methods. It also revealed that the highly linear relation was held between the estimated heart rate and ground truth with the correlation coefficients of 0.89 and 0.99, respectively. CONCLUSION By extracting illumination variation directly from the facial region of interest rather than from the background region of interest, the proposed method demonstrates that it can overcome the drawbacks of the previous methods due to the illumination variation difference between the background and facial regions of interest. It can be found that the proposed method has a relatively good robustness regardless of whether illumination variation exists or not.
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Affiliation(s)
- JongSong Ryu
- School of Physics, Northeast Normal University, Changchun 130022, China; Faculty of Physics, University of Science, Pyongyang, Democratic People's Republic of Korea.
| | - SunChol Hong
- Academy of Ultramodern Science, Kim Il Sung University, Pyongyang, Democratic People's Republic of Korea.
| | - Shili Liang
- School of Physics, Northeast Normal University, Changchun 130022, China.
| | - SinIl Pak
- Faculty of Communications, Kim Chaek University of Technology, Pyongyang, Democratic People's Republic of Korea.
| | - Qingyue Chen
- School of Physics, Northeast Normal University, Changchun 130022, China
| | - Shifeng Yan
- School of Physics, Northeast Normal University, Changchun 130022, China
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30
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Sun Z, He Q, Li Y, Wang W, Wang RK. Robust non-contact peripheral oxygenation saturation measurement using smartphone-enabled imaging photoplethysmography. BIOMEDICAL OPTICS EXPRESS 2021; 12:1746-1760. [PMID: 33796384 PMCID: PMC7984770 DOI: 10.1364/boe.419268] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/04/2021] [Accepted: 02/09/2021] [Indexed: 06/12/2023]
Abstract
We propose a robust non-contact method to accurately estimate peripheral oxygen saturation (SpO2) using a smartphone-based imaging photoplethysmography. The method utilizes the built-in color camera as a remote sensor and the built-in flashlight as illumination to estimate the SpO2. Following the ratio of ratios between green and red channels, we introduce a multiple linear regression algorithm to improve the SpO2 estimation. The algorithm considers the ratio of ratios and the reflectance images recorded at the RGB channels during a calibration process to obtain a set of weighting coefficients to weigh each contributor to the final determination of SpO2. We demonstrate the proposed smartphone-based method of estimating the SpO2 on five healthy volunteers whose arms are conditioned by a manual pressure cuff to manipulate the SpO2 between 90∼100% as detected simultaneously by a medical-grade pulse oximeter. Experimental results indicate that the overall estimated error between the smartphone and the reference pulse oximeter is 0.029 ± 1.141%, leading to a 43% improvement over the conventional ratio of ratios method (0.008 ± 2.008%). In addition, the data sampling time in the current method is 2 seconds, similar to the sampling cycle used in the commercial medical-grade pulse oximeters.
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Affiliation(s)
- Zhiyuan Sun
- Department of Bioengineering, University of Washington, Seattle, Washington 98105, USA
- The authors contributed equally
| | - Qinghua He
- Department of Bioengineering, University of Washington, Seattle, Washington 98105, USA
- The authors contributed equally
| | - Yuandong Li
- Department of Bioengineering, University of Washington, Seattle, Washington 98105, USA
| | - Wendy Wang
- Department of Bioengineering, University of Washington, Seattle, Washington 98105, USA
| | - Ruikang K. Wang
- Department of Bioengineering, University of Washington, Seattle, Washington 98105, USA
- Department of Ophthalmology, University of Washington, Seattle, Washington 98109, USA
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31
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Galeb HA, Wilkinson EL, Stowell AF, Lin H, Murphy ST, Martin‐Hirsch PL, Mort RL, Taylor AM, Hardy JG. Melanins as Sustainable Resources for Advanced Biotechnological Applications. GLOBAL CHALLENGES (HOBOKEN, NJ) 2021; 5:2000102. [PMID: 33552556 PMCID: PMC7857133 DOI: 10.1002/gch2.202000102] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/04/2020] [Indexed: 05/17/2023]
Abstract
Melanins are a class of biopolymers that are widespread in nature and have diverse origins, chemical compositions, and functions. Their chemical, electrical, optical, and paramagnetic properties offer opportunities for applications in materials science, particularly for medical and technical uses. This review focuses on the application of analytical techniques to study melanins in multidisciplinary contexts with a view to their use as sustainable resources for advanced biotechnological applications, and how these may facilitate the achievement of the United Nations Sustainable Development Goals.
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Affiliation(s)
- Hanaa A. Galeb
- Department of ChemistryLancaster UniversityLancasterLA1 4YBUK
- Department of ChemistryScience and Arts CollegeRabigh CampusKing Abdulaziz UniversityJeddah21577Saudi Arabia
| | - Emma L. Wilkinson
- Department of Biomedical and Life SciencesLancaster UniversityLancasterLA1 4YGUK
| | - Alison F. Stowell
- Department of Organisation, Work and TechnologyLancaster University Management SchoolLancaster UniversityLancasterLA1 4YXUK
| | - Hungyen Lin
- Department of EngineeringLancaster UniversityLancasterLA1 4YWUK
| | - Samuel T. Murphy
- Department of EngineeringLancaster UniversityLancasterLA1 4YWUK
- Materials Science InstituteLancaster UniversityLancasterLA1 4YBUK
| | - Pierre L. Martin‐Hirsch
- Lancashire Teaching Hospitals NHS TrustRoyal Preston HospitalSharoe Green LanePrestonPR2 9HTUK
| | - Richard L. Mort
- Department of Biomedical and Life SciencesLancaster UniversityLancasterLA1 4YGUK
| | - Adam M. Taylor
- Lancaster Medical SchoolLancaster UniversityLancasterLA1 4YWUK
| | - John G. Hardy
- Department of ChemistryLancaster UniversityLancasterLA1 4YBUK
- Materials Science InstituteLancaster UniversityLancasterLA1 4YBUK
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32
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De Landro M, Espíritu García-Molina I, Barberio M, Felli E, Agnus V, Pizzicannella M, Diana M, Zappa E, Saccomandi P. Hyperspectral Imagery for Assessing Laser-Induced Thermal State Change in Liver. SENSORS 2021; 21:s21020643. [PMID: 33477656 PMCID: PMC7831494 DOI: 10.3390/s21020643] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/05/2021] [Accepted: 01/13/2021] [Indexed: 12/16/2022]
Abstract
This work presents the potential of hyperspectral imaging (HSI) to monitor the thermal outcome of laser ablation therapy used for minimally invasive tumor removal. Our main goal is the establishment of indicators of the thermal damage of living tissues, which can be used to assess the effect of the procedure. These indicators rely on the spectral variation of temperature-dependent tissue chromophores, i.e., oxyhemoglobin, deoxyhemoglobin, methemoglobin, and water. Laser treatment was performed at specific temperature thresholds (from 60 to 110 °C) on in-vivo animal liver and was assessed with a hyperspectral camera (500-995 nm) during and after the treatment. The indicators were extracted from the hyperspectral images after the following processing steps: the breathing motion compensation and the spectral and spatial filtering, the selection of spectral bands corresponding to specific tissue chromophores, and the analysis of the areas under the curves for each spectral band. Results show that properly combining spectral information related to deoxyhemoglobin, methemoglobin, lipids, and water allows for the segmenting of different zones of the laser-induced thermal damage. This preliminary investigation provides indicators for describing the thermal state of the liver, which can be employed in the future as clinical endpoints of the procedure outcome.
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Affiliation(s)
- Martina De Landro
- Department of Mechanical Engineering, Politecnico di Milano, 20156 Milan, Italy; (M.D.L.); (I.E.G.-M.); (E.Z.)
| | | | - Manuel Barberio
- IHU-Strasbourg, 67000 Strasbourg, France; (M.B.); (E.F.); (V.A.); (M.P.); (M.D.)
- Department of General Surgery, Ospedale Card. G. Panico, 73039 Tricase, Italy
| | - Eric Felli
- IHU-Strasbourg, 67000 Strasbourg, France; (M.B.); (E.F.); (V.A.); (M.P.); (M.D.)
| | - Vincent Agnus
- IHU-Strasbourg, 67000 Strasbourg, France; (M.B.); (E.F.); (V.A.); (M.P.); (M.D.)
| | | | - Michele Diana
- IHU-Strasbourg, 67000 Strasbourg, France; (M.B.); (E.F.); (V.A.); (M.P.); (M.D.)
- Research Institute against Cancer of the Digestive System IRCAD, 67091 Strasbourg, France
- ICube Laboratory, Photonics Instrumentation for Health, 67400 Strasbourg, France
| | - Emanuele Zappa
- Department of Mechanical Engineering, Politecnico di Milano, 20156 Milan, Italy; (M.D.L.); (I.E.G.-M.); (E.Z.)
| | - Paola Saccomandi
- Department of Mechanical Engineering, Politecnico di Milano, 20156 Milan, Italy; (M.D.L.); (I.E.G.-M.); (E.Z.)
- Correspondence:
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33
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Bowden AK, Durr NJ, Erickson D, Ozcan A, Ramanujam N, Jacques PV. Optical Technologies for Improving Healthcare in Low-Resource Settings: introduction to the feature issue. BIOMEDICAL OPTICS EXPRESS 2020; 11:3091-3094. [PMID: 32637243 PMCID: PMC7316015 DOI: 10.1364/boe.397698] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Indexed: 05/03/2023]
Abstract
This feature issue of Biomedical Optics Express presents a cross-section of interesting and emerging work of relevance to optical technologies in low-resource settings. In particular, the technologies described here aim to address challenges to meeting healthcare needs in resource-constrained environments, including in rural and underserved areas. This collection of 18 papers includes papers on both optical system design and image analysis, with applications demonstrated for ex vivo and in vivo use. All together, these works portray the importance of global health research to the scientific community and the role that optics can play in addressing some of the world's most pressing healthcare challenges.
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Affiliation(s)
- Audrey K. Bowden
- Vanderbilt Biophotonics Center, Department of Biomedical Engineering, Vanderbilt University, 410 24th Avenue South, Nashville, TN 37232, USA
| | - Nicholas J. Durr
- Department of Biomedical Engineering, Johns Hopkins University (JHU), 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - David Erickson
- Cornell University, 9 Millcroft Way, Ithaca, NY 14850, USA
| | - Aydogan Ozcan
- Department of Electrical and Computer Engineering, University of California Los Angeles, Los Angeles CA 90095, USA
| | - Nirmala Ramanujam
- Duke University, 101 Science Drive, 1427 FCIEMAS, Durham, NC 27708, USA
| | - Paulino Vacas Jacques
- Wellman Center for Photomedicine, Massachusetts General Hospital, 55 Fruit St, Boston, MA 02114, USA
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