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Park J, Overbey EG, Narayanan SA, Kim J, Tierney BT, Damle N, Najjar D, Ryon KA, Proszynski J, Kleinman A, Hirschberg JW, MacKay M, Afshin EE, Granstein R, Gurvitch J, Hudson BM, Rininger A, Mullane S, Church SE, Meydan C, Church G, Beheshti A, Mateus J, Mason CE. Spatial multi-omics of human skin reveals KRAS and inflammatory responses to spaceflight. Nat Commun 2024; 15:4773. [PMID: 38862494 PMCID: PMC11166909 DOI: 10.1038/s41467-024-48625-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Accepted: 04/26/2024] [Indexed: 06/13/2024] Open
Abstract
Spaceflight can change metabolic, immunological, and biological homeostasis and cause skin rashes and irritation, yet the molecular basis remains unclear. To investigate the impact of short-duration spaceflight on the skin, we conducted skin biopsies on the Inspiration4 crew members before (L-44) and after (R + 1) flight. Leveraging multi-omics assays including GeoMx™ Digital Spatial Profiler, single-cell RNA/ATAC-seq, and metagenomics/metatranscriptomics, we assessed spatial gene expressions and associated microbial and immune changes across 95 skin regions in four compartments: outer epidermis, inner epidermis, outer dermis, and vasculature. Post-flight samples showed significant up-regulation of genes related to inflammation and KRAS signaling across all skin regions. These spaceflight-associated changes mapped to specific cellular responses, including altered interferon responses, DNA damage, epithelial barrier disruptions, T-cell migration, and hindered regeneration were located primarily in outer tissue compartments. We also linked epithelial disruption to microbial shifts in skin swab and immune cell activity to PBMC single-cell data from the same crew and timepoints. Our findings present the inaugural collection and examination of astronaut skin, offering insights for future space missions and response countermeasures.
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Affiliation(s)
- Jiwoon Park
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, USA
| | - Eliah G Overbey
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, USA
| | - S Anand Narayanan
- Department of Nutrition & Integrative Physiology, Florida State University, Tallahassee, FL, USA
| | - JangKeun Kim
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, USA
| | - Braden T Tierney
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, USA
| | - Namita Damle
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
| | - Deena Najjar
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
| | - Krista A Ryon
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
| | - Jacqueline Proszynski
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
| | - Ashley Kleinman
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
| | - Jeremy Wain Hirschberg
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
| | - Matthew MacKay
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
| | - Evan E Afshin
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
| | - Richard Granstein
- Department of Dermatology, Weill Cornell Medicine, New York, NY, USA
| | - Justin Gurvitch
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
| | | | | | | | | | - Cem Meydan
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, USA
| | - George Church
- Department of Genetics, Harvard Medical School, Boston, MA, 02115, USA
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
| | - Afshin Beheshti
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Blue Marble Space Institute of Science, Space Biosciences Division, NASA Ames Research Center, Moffett Field, CA, USA
| | | | - Christopher E Mason
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA.
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, USA.
- The Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA.
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Sadrzadeh-Afsharazar F, Raizman R, Saiko G. Utility of Thermographic Imaging for Callus Identification in Wound and Foot Care. SENSORS (BASEL, SWITZERLAND) 2023; 23:9376. [PMID: 38067749 PMCID: PMC10708640 DOI: 10.3390/s23239376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 11/09/2023] [Accepted: 11/14/2023] [Indexed: 12/18/2023]
Abstract
Calluses are thickened skin areas that develop due to repeated friction, pressure, or other types of irritation. While calluses are usually harmless and formed as a protective surface, they can lead to skin ulceration or infection if left untreated. As calluses are often not clearly visible to the patients, and some areas of dead skin can be missed during debridement, accessory tools can be useful in assessment and follow-up. The practical question addressed in this article is whether or not thermal imaging adds value to callus assessment. We have performed a theoretical analysis of the feasibility of thermographic imaging for callus identification. Our analytical calculations show that the temperature drop in the epidermis should be on the order of 0.1 °C for the normal epidermis in hairy skin, 0.9 °C for glabrous skin, and 1.5-2 °C or higher in calluses. We have validated our predictions on gelatin phantoms and demonstrated the feasibility of thermographic imaging for callus identification in two clinical case series. Our experimental results are in agreement with theoretical predictions and support the notion that local skin temperature variations can indicate epidermis thickness variations, which can be used for callus identification. In particular, a surface temperature drop on the order of 0.5 °C or more can be indicative of callus presence, particularly in callus-prone areas. In addition, our analytical calculations and phantom experiments show the importance of ambient temperature measurements during thermographic assessments.
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Affiliation(s)
- Faraz Sadrzadeh-Afsharazar
- Department of Electrical, Computer and Biomedical Engineering, Toronto Metropolitan University, Toronto, ON M5B 2K3, Canada
| | - Rose Raizman
- Lawrence S. Bloomberg Faculty of Nursing, University of Toronto, Toronto, ON M5S 1A8, Canada
- Scarborough Health Network, Toronto, ON M1E 4B9, Canada
| | - Gennadi Saiko
- Department of Physics, Toronto Metropolitan University, Toronto, ON M5B 2K3, Canada
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Akitegetse C, Poirier J, Sauvageau D. Sensitivity of visible range multi-wavelength algorithms for retinal tissue oximetry to acquisition parameters. BIOMEDICAL OPTICS EXPRESS 2023; 14:4296-4309. [PMID: 37799705 PMCID: PMC10549742 DOI: 10.1364/boe.495721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 06/16/2023] [Accepted: 07/18/2023] [Indexed: 10/07/2023]
Abstract
This study examined the sensitivity of broadband spectroscopy algorithms for retinal tissue oximetry to spectral acquisition parameters. Monte Carlo simulations were conducted on a 4-layer retinal model to assess the impact of various parameters. The optimal spectral range for accurate measurements was determined to be 530 nm to 585 nm. Decreased spectral resolution below 4 nm significantly reduced accuracy. Using an acquisition area larger than the blood vessel resulted in an underestimation of oxygen saturation, especially for high values. A threshold was observed where increased light intensity had no significant impact on measurement variability. The study highlights the importance of informed parameter selection for accurately assessing retinal microcapillary oxygenation and studying local hemodynamics.
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Affiliation(s)
| | | | - Dominic Sauvageau
- Zilia inc., Québec, QC, G1K 3G5, Canada
- Chemical and Materials Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada
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Li S, Xiao K, Li P. Spectra Reconstruction for Human Facial Color from RGB Images via Clusters in 3D Uniform CIELab* and Its Subordinate Color Space. SENSORS (BASEL, SWITZERLAND) 2023; 23:s23020810. [PMID: 36679603 PMCID: PMC9861444 DOI: 10.3390/s23020810] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 12/13/2022] [Accepted: 12/15/2022] [Indexed: 06/12/2023]
Abstract
Previous research has demonstrated the potential to reconstruct human facial skin spectra based on the responses of RGB cameras to achieve high-fidelity color reproduction of human facial skin in various industrial applications. Nonetheless, the level of precision is still expected to improve. Inspired by the asymmetricity of human facial skin color in the CIELab* color space, we propose a practical framework, HPCAPR, for skin facial reflectance reconstruction based on calibrated datasets which reconstruct the facial spectra in subsets derived from clustering techniques in several spectrometric and colorimetric spaces, i.e., the spectral reflectance space, Principal Component (PC) space, CIELab*, and its three 2D subordinate color spaces, La*, Lb*, and ab*. The spectra reconstruction algorithm is optimized by combining state-of-art algorithms and thoroughly scanning the parameters. The results show that the hybrid of PCA and RGB polynomial regression algorithm with 3PCs plus 1st-order polynomial extension gives the best results. The performance can be improved substantially by operating the spectral reconstruction framework within the subset classified in the La* color subspace. Comparing with not conducting the clustering technique, it attains values of 25.2% and 57.1% for the median and maximum errors for the best cluster, respectively; for the worst, the maximum error was reduced by 42.2%.
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Affiliation(s)
- Suixian Li
- Flying College, Binzhou University, Binzhou 256600, China
- School of Design, University of Leeds, Leeds LS2 9JT, UK
| | - Kaida Xiao
- School of Design, University of Leeds, Leeds LS2 9JT, UK
| | - Pingqi Li
- School of Informatic, University of Edinburg, Edinburgh EH8 9YL, UK
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Saiko G. How Skin Color Depends on Tissue Oxygenation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1438:101-105. [PMID: 37845447 DOI: 10.1007/978-3-031-42003-0_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
BACKGROUND Skin color is essential to skin and wound assessment as it brings valuable information about skin physiology and pathology. An approach, which can help deconvolute and isolate various mechanisms affecting skin color, could be helpful to drive the remote photoplethysmography (rPPG) utility beyond its current applications. AIM The present work aims to create a simple analytical framework that links skin color with blood oxygenation and perfusion. MATERIAL AND METHODS The model consists of two parts. First, the model's core connects changes in tissue chromophore concentrations with changes in tissue reflectance. In the second step, the tissue reflectance is convoluted with the response curves of a sensor (tristimulus response in the case of the human eye) and the light source's spectrum. RESULTS The model allows linking changes in blood oxygenation and perfusion with changes in skin color. CONCLUSION The model can be helpful for the interpretation of the amplitudes of various components of the rPPG signal.
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Affiliation(s)
- Gennadi Saiko
- Swift Medical Inc., Toronto, Canada.
- Department of Physics, Toronto Metropolitan University, Toronto, Canada.
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Skin Microbial Changes during Space Flights: A Systematic Review. Life (Basel) 2022; 12:life12101498. [PMID: 36294933 PMCID: PMC9604750 DOI: 10.3390/life12101498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 09/19/2022] [Accepted: 09/22/2022] [Indexed: 11/17/2022] Open
Abstract
Background. Sixty years after the launch of the first human into space, different studies on the physiological changes that humans undergo during dynamic flight phases and prolonged weightlessness have been undertaken. Understanding these changes is important for the creation of the preventative measures that are essential to ensuring astronaut health. Among these changes, those of the skin are frequent, despite being rarely treated during missions. The skin is a physical barrier that protects the body from pathogen invasion and environmental changes, and it harbors diverse microbial communities that form the skin microbiota. Methods. A systematic literature review of skin microbiome changes during space flight was conducted using public electronic databases (PubMed and Scopus) selecting studies published from 2015 to 2022. The systematic review was performed according to 2020 PRISMA guidelines. Results. A total of 17 studies were collected and, after screening for inclusion and exclusion criteria, eight studies were included in this review. According to the examined literature, some skin microbiota changes seems to be only temporary, in particular Gamma- and Betaproteobacteria abundance tends to decrease, while the occurrence of the Malassezia species and Firmicutes, including Staphylococcus and Streptococcus, tends to increase. At the same time, there seems to be an exchange of microorganisms between astronauts and between the confined environment and a single astronaut, with alterations in the proportion of microorganisms maintained during the flight, in particular for species such as Corynebacterium spp., Staphylococcus spp., Streptococcus spp. and Cloacibacterium spp. Given that skin contributes both to protecting the body from pathogen invasion and environmental changes and to maintaining human homeostasis, changes in the skin microbiota of astronauts might result in skin diseases. Discussion. The skin microbiota of astronauts seems to influence the microbial composition of the International Space Station, but further studies should be performed to better understand skin microbiota dynamics and to prevent the development of dermatologic conditions during space flight.
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Co-Graft of Acellular Dermal Matrix and Split Thickness Skin Graft—A New Reconstructive Surgical Method in the Treatment of Hidradenitis Suppurativa. Bioengineering (Basel) 2022; 9:bioengineering9080389. [PMID: 36004913 PMCID: PMC9404734 DOI: 10.3390/bioengineering9080389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 08/04/2022] [Accepted: 08/12/2022] [Indexed: 11/17/2022] Open
Abstract
Hidradenitis suppurativa is a chronic disease that significantly reduces patients’ quality of life. Patients are chronically treated with systemic therapies, which are often ineffective. Surgical treatment for severe cases of hidradenitis suppurativa is one option for affected patients. Surgical treatment has its limitations, and wound closure may be particularly problematic. This requires the use of reconstructive techniques. The methods of choice for wound closure are split-thickness skin grafts or local flaps reconstructions. However, each method has its limitations. This is a presentation of a new reconstructive surgical method in hidradenitis suppurativa surgery: the use of a co-graft of Acellular dermal matrix and split thickness skin graft as a novel method in wound closure after wide excisions, based on two cases. The results of this method are very promising: we achieved very fast wound closure with good aesthetic results regarding scar formation. In this paper, we used several examinations: laser speckle analysis, cutometer tests, and health-related quality of life (QoL) questionnaire to check the clinical impact of this method. Our initial results are very encouraging. ADM with STSG as a co-graft could be widely used in reconstructive surgery. This is a preliminary study, which should be continued in further, extended research.
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The Finite Element Analysis Research on Microneedle Design Strategy and Transdermal Drug Delivery System. Pharmaceutics 2022; 14:pharmaceutics14081625. [PMID: 36015251 PMCID: PMC9413279 DOI: 10.3390/pharmaceutics14081625] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 07/28/2022] [Accepted: 07/28/2022] [Indexed: 02/04/2023] Open
Abstract
Microneedles (MNs) as a novel transdermal drug delivery system have shown great potential for therapeutic and disease diagnosis applications by continually providing minimally invasive, portable, cost-effective, high bioavailability, and easy-to-use tools compared to traditional parenteral administrations. However, microneedle transdermal drug delivery is still in its infancy. Many research studies need further in-depth exploration, such as safety, structural characteristics, and drug loading performance evaluation. Finite element analysis (FEA) uses mathematical approximations to simulate real physical systems (geometry and load conditions). It can simplify complex engineering problems to guide the precise preparation and potential industrialization of microneedles, which has attracted extensive attention. This article introduces FEA research for microneedle transdermal drug delivery systems, focusing on microneedle design strategy, skin mechanics models, skin permeability, and the FEA research on drug delivery by MNs.
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Kondziołka J, Wilczyński S, Michalecki Ł. Potential Use of Novel Image and Signal Processing Methods to Develop a Quantitative Assessment of the Severity of Acute Radiation Dermatitis in Breast Cancer Radiotherapy. Clin Cosmet Investig Dermatol 2022; 15:725-733. [PMID: 35497689 PMCID: PMC9041143 DOI: 10.2147/ccid.s354320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 03/18/2022] [Indexed: 11/23/2022]
Abstract
More than 95% of patients who undergo radiotherapy report symptoms of radiation dermatitis, which is a side effect of this therapy. Erythema, edema, dry and moist desquamation intensify with each fraction of irradiation and can significantly reduce a patient's quality of life. Therefore, an effective skin care procedure is needed for skin that has been exposed to ionizing radiation in order to avoid unplanned treatment interruptions. The methods that are currently used to assess the severity of an acute radiation reaction are based on visual scales (RTOG, EORTC, NCI CTCAE, LENT-SOMA). Because the assessment is made subjectively, the results depend on the researchers, their experience and perceptiveness. Until now, several studies have been carried out to check the possibility of using an objective methods like hyperspectral imaging, thermal imaging, laser Doppler flowmetry, dielectric and electrochemical methods, reflection spectrophotometry and Courage-Khazaka Multi-skin instrument to radiation-induced dermatitis assessment. Unfortunately, due to various limitations that occurred in the research, none of these techniques was successfully implement as alternative for visual assessment. The continuous development of technology enables researchers to access new techniques that might constitute useful diagnostic and cognitive tools. Infrared thermal imaging, hyperspectral imaging and reflectance spectroscopy are examples of the visual techniques that have been used for many years in various fields of medicine, including dermatology and chronic wound or burn care. They provide information on the skin parameters, such as the temperature, concentration and distribution of chromophores (eg, hemoglobin and melanin), saturation or perfusion changes. The aim of this study is to review the available literature on the use of imaging methods in the clinical assessment of skin with lesions of various origins, evaluation of their suitability for the assessment of radiation reaction and consideration the possibility of creating a quantitative scale for assessing severity of acute radiation dermatitis.
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Affiliation(s)
- Joanna Kondziołka
- Department of Basic Biomedical Science, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Sławomir Wilczyński
- Department of Basic Biomedical Science, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Łukasz Michalecki
- University Clinical Center of the Medical University of Silesia, Katowice, Poland
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Jet injectors: Perspectives for small volume delivery with lasers. Adv Drug Deliv Rev 2022; 182:114109. [PMID: 34998902 DOI: 10.1016/j.addr.2021.114109] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 12/16/2021] [Accepted: 12/29/2021] [Indexed: 12/27/2022]
Abstract
Needle-free jet injectors have been proposed as an alternative to injections with hypodermic needles. Currently, a handful of commercial needle-free jet injectors already exist. However, these injectors are designed for specific injections, typically limited to large injection volumes into the deeper layers beneath the skin. There is growing evidence of advantages when delivering small volumes into the superficial skin layers, namely the epidermis and dermis. Injections such as vaccines and insulin would benefit from delivery into these superficial layers. Furthermore, the same technology for small volume needle-free injections can serve (medical) tattooing as well as other personalized medicine treatments. The research dedicated to needle-free jet injectors actuated by laser energy has increased in the last decade. In this case, the absorption of the optical energy by the liquid results in an explosively growing bubble. This bubble displaces the rest of the liquid, resulting in a fast microfluidic jet which can penetrate the skin. This technique allows for precise control over volumes (pL to µL) and penetration depths (µm to mm). Furthermore, these injections can be tuned without changing the device, by varying parameters such as laser power, beam diameter and filling level of the liquid container. Despite the published research on the working principles and capabilities of individual laser-actuated jet injectors, a thorough overview encompassing all of them is lacking. In this perspective, we will discuss the current status of laser-based jet injectors and contrast their advantages and limitations, as well as their potential and challenges.
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11
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Geldof F, Dashtbozorg B, Hendriks BHW, Sterenborg HJCM, Ruers TJM. Layer thickness prediction and tissue classification in two-layered tissue structures using diffuse reflectance spectroscopy. Sci Rep 2022; 12:1698. [PMID: 35105926 PMCID: PMC8807816 DOI: 10.1038/s41598-022-05751-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 01/12/2022] [Indexed: 11/26/2022] Open
Abstract
During oncological surgery, it can be challenging to identify the tumor and establish adequate resection margins. This study proposes a new two-layer approach in which diffuse reflectance spectroscopy (DRS) is used to predict the top layer thickness and classify the layers in two-layered phantom and animal tissue. Using wavelet-based and peak-based DRS spectral features, the proposed method could predict the top layer thickness with an accuracy of up to 0.35 mm. In addition, the tissue types of the first and second layers were classified with an accuracy of 0.95 and 0.99. Distinguishing multiple tissue layers during spectral analyses results in a better understanding of more complex tissue structures encountered in surgical practice.
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Affiliation(s)
- Freija Geldof
- Department of Surgery, Netherlands Cancer Institute, 1066 CX, Amsterdam, The Netherlands.
| | - Behdad Dashtbozorg
- Department of Surgery, Netherlands Cancer Institute, 1066 CX, Amsterdam, The Netherlands
| | - Benno H W Hendriks
- Department of IGT and US Devices & Systems, Philips Research Laboratories, 5656 AE, Eindhoven, The Netherlands
- Department of BioMechanical Engineering, 3mE, Delft University of Technology, 2628 CD, Delft, The Netherlands
| | - Henricus J C M Sterenborg
- Department of Surgery, Netherlands Cancer Institute, 1066 CX, Amsterdam, The Netherlands
- Department of Biomedical Engineering and Physics, Amsterdam University Medical Center, 1105 AZ, Amsterdam, The Netherlands
| | - Theo J M Ruers
- Department of Surgery, Netherlands Cancer Institute, 1066 CX, Amsterdam, The Netherlands
- Faculty of Science and Technology, University of Twente, 7522 NB, Enschede, The Netherlands
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12
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Saiko G. Improved Optical Tissue Model for Tissue Oximetry Imaging Applications. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1395:211-215. [PMID: 36527639 DOI: 10.1007/978-3-031-14190-4_35] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Chronic, non-healing wounds are a growing concern in healthcare delivery. Tissue oxygenation is recognised as critical to successful wound healing. However, the quality and quantity of the information extracted by hyperspectral imaging depend on the optical tissue model. This article aims to develop a simplified and computationally efficient approach comparable in quality with the two-layer model. METHODS We have considered the epidermal layer as a 'thin-film' within the dermal layer. By considering the mismatched boundary and developing a four-flux model for light transport within the tissue, we have obtained a quasi two-layer model with a closed-form solution similar to the single-layer model. RESULTS We have compared the developed model with the two-layer model (reference) and the single-layer model for the broad range of physiologically relevant parameters. The thickness of the epithelium: 50, 80, and 120 μm. Melanin concentration: 1, 2, 4, 8, 16, and 32%. Blood concentration: 0.2%, 1%, and 7%. Oxygen saturation: 60%, 80%, and 99%. Our initial results show that the accuracy of the proposed quasi two-layer model significantly (by a factor of 10) outperforms the single-layer model and is in close agreement with the two-layer model. CONCLUSIONS The proposed quasi two-layer model significantly (by the factor of 10) outperforms the single-layer model and is closely aligned with the two-layer model.
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Vasudevan V, Narayanan Unni S. Quantification of soft tissue parameters from spatially resolved diffuse reflectance finite element models. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2022; 38:e3546. [PMID: 34719121 DOI: 10.1002/cnm.3546] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/26/2021] [Accepted: 10/27/2021] [Indexed: 06/13/2023]
Abstract
Spatially resolved diffuse reflectance spectroscopy (SRDRS) is a non-invasive optical technique that helps in clinical diagnosis of various tissue microcirculation and skin pigmentation disorders based on collected backscattered light from multi-layered tissue. The extraction of the optical properties from the reflectance spectrum using analytical solutions is laborious. Model-based light tissue interaction studies help in quantifying the optical properties. This work presents the use of finite element models of light tissue interaction for this purpose. A bilayer model mimicking human skin was considered and the diffused reflectance spectra at multiple detector points were generated using finite element modelling for varying melanin concentration, epidermal thickness, blood volume fraction, oxygen saturation and scattering components. The reflectance value based on varying optical parameters from multiple detection points lead to the generation of a look-up table (LUT), which is further used for finding the tissue parameters that contribute to the spatially resolved reflectance values. The tissue parameters estimated after inverse modelling showed a high degree of agreement with the expected tissue parameters for a test dataset different from the training dataset.
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Affiliation(s)
- Vysakh Vasudevan
- Biophotonics Laboratory, Department of Applied Mechanics, Indian Institute of Technology Madras, Chennai, India
| | - Sujatha Narayanan Unni
- Biophotonics Laboratory, Department of Applied Mechanics, Indian Institute of Technology Madras, Chennai, India
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14
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Aleemardani M, Trikić MZ, Green NH, Claeyssens F. The Importance of Mimicking Dermal-Epidermal Junction for Skin Tissue Engineering: A Review. Bioengineering (Basel) 2021; 8:bioengineering8110148. [PMID: 34821714 PMCID: PMC8614934 DOI: 10.3390/bioengineering8110148] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 10/14/2021] [Accepted: 10/16/2021] [Indexed: 12/11/2022] Open
Abstract
There is a distinct boundary between the dermis and epidermis in the human skin called the basement membrane, a dense collagen network that creates undulations of the dermal-epidermal junction (DEJ). The DEJ plays multiple roles in skin homeostasis and function, namely, enhancing the adhesion and physical interlock of the layers, creating niches for epidermal stem cells, regulating the cellular microenvironment, and providing a physical boundary layer between fibroblasts and keratinocytes. However, the primary role of the DEJ has been determined as skin integrity; there are still aspects of it that are poorly investigated. Tissue engineering (TE) has evolved promising skin regeneration strategies and already developed TE scaffolds for clinical use. However, the currently available skin TE equivalents neglect to replicate the DEJ anatomical structures. The emergent ability to produce increasingly complex scaffolds for skin TE will enable the development of closer physical and physiological mimics to natural skin; it also allows researchers to study the DEJ effect on cell function. Few studies have created patterned substrates that could mimic the human DEJ to explore their significance. Here, we first review the DEJ roles and then critically discuss the TE strategies to create the DEJ undulating structure and their effects. New approaches in this field could be instrumental for improving bioengineered skin substitutes, creating 3D engineered skin, identifying pathological mechanisms, and producing and screening drugs.
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Affiliation(s)
- Mina Aleemardani
- Biomaterials and Tissue Engineering Group, Department of Materials Science and Engineering, Kroto Research Institute, The University of Sheffield, Sheffield S3 7HQ, UK; (M.A.); (M.Z.T.); (N.H.G.)
| | - Michael Zivojin Trikić
- Biomaterials and Tissue Engineering Group, Department of Materials Science and Engineering, Kroto Research Institute, The University of Sheffield, Sheffield S3 7HQ, UK; (M.A.); (M.Z.T.); (N.H.G.)
| | - Nicola Helen Green
- Biomaterials and Tissue Engineering Group, Department of Materials Science and Engineering, Kroto Research Institute, The University of Sheffield, Sheffield S3 7HQ, UK; (M.A.); (M.Z.T.); (N.H.G.)
- Insigneo Institute for in Silico Medicine, The Pam Liversidge Building, Sir Robert Hadfield Building, Mappin Street, Sheffield S1 3JD, UK
| | - Frederik Claeyssens
- Biomaterials and Tissue Engineering Group, Department of Materials Science and Engineering, Kroto Research Institute, The University of Sheffield, Sheffield S3 7HQ, UK; (M.A.); (M.Z.T.); (N.H.G.)
- Correspondence:
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Proposal for a Skin Layer-Wise Decomposition Model of Spatially-Resolved Diffuse Reflectance Spectra Based on Maximum Depth Photon Distributions: A Numerical Study. PHOTONICS 2021. [DOI: 10.3390/photonics8100444] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In the context of cutaneous carcinoma diagnosis based on in vivo optical biopsy, Diffuse Reflectance (DR) spectra, acquired using a Spatially Resolved (SR) sensor configuration, can be analyzed to distinguish healthy from pathological tissues. The present contribution aims at studying the depth distribution of SR-DR-detected photons in skin from the perspective of analyzing how these photons contribute to acquired spectra carrying local physiological and morphological information. Simulations based on modified Cuda Monte Carlo Modeling of Light transport were performed on a five-layer human skin optical model with epidermal thickness, phototype and dermal blood content as variable parameters using (i) wavelength-resolved scattering and absorption properties and (ii) the geometrical configuration of a multi-optical fiber probe implemented on an SR-DR spectroscopic device currently used in clinics. Through histograms of the maximum probed depth and their exploitation, we provide numerical evidence linking the characteristic penetration depth of the detected photons to their wavelengths and four source–sensor distances, which made it possible to propose a decomposition of the DR signals related to skin layer contributions.
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16
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Chiba T, Murata M, Kawano T, Hashizume M, Akahoshi T. Reflectance spectra analysis for mucous assessment. World J Gastrointest Oncol 2021; 13:822-834. [PMID: 34457188 PMCID: PMC8371524 DOI: 10.4251/wjgo.v13.i8.822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 04/26/2021] [Accepted: 07/09/2021] [Indexed: 02/06/2023] Open
Abstract
This review report represents an overview of research and development on medical hyperspectral imaging technology and its applications. Spectral imaging technology is attracting attention as a new imaging modality for medical applications, especially in disease diagnosis and image-guided surgery. Considering the recent advances in imaging, this technology provides an opportunity for two-dimensional mapping of oxygen saturation (SatO2) of blood with high accuracy, spatial spectral imaging, and its analysis and provides detection and diagnostic information about the tissue physiology and morphology. Multispectral imaging also provides information about tissue oxygenation, perfusion, and potential function during surgery. Analytical algorithm has been examined, and indication of accurate map of relative hemoglobin concentration and SatO2 can be indicated with preferable resolution and frame rate. This technology is expected to provide promising biomedical information in practical use. Several studies suggested that blood flow and SatO2 are associated with gastrointestinal disorders, particularly malignant tumor conditions. The use and analysis of spectroscopic images are expected to potentially play a role in the detection and diagnosis of these diseases.
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Affiliation(s)
- Toru Chiba
- Pentax_LifeCare, HOYA Corporation, Akishima-shi 196-0012, Tokyo, Japan
| | - Masaharu Murata
- Center for Advanced Medical Innovation, Kyushu University, Fukuoka-shi 812-8582, Fukuoka, Japan
| | - Takahito Kawano
- Center for Advanced Medical Innovation, Kyushu University, Fukuoka-shi 812-8582, Fukuoka, Japan
| | - Makoto Hashizume
- Center for Advanced Medical Innovation, Kyushu University, Fukuoka-shi 812-8582, Fukuoka, Japan
| | - Tomohiko Akahoshi
- Department of Disaster and Emergency Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka_shi 812-8582, Fukuoka, Japan
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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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Bjorgan A, Randeberg LL. Exploiting scale-invariance: a top layer targeted inverse model for hyperspectral images of wounds. BIOMEDICAL OPTICS EXPRESS 2020; 11:5070-5091. [PMID: 33014601 PMCID: PMC7510863 DOI: 10.1364/boe.399636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/15/2020] [Accepted: 07/28/2020] [Indexed: 05/10/2023]
Abstract
Detection of re-epithelialization in wound healing is important, but challenging. Hyperspectral imaging can be used for non-destructive characterization, but efficient techniques are needed to extract and interpret the information. An inverse photon transport model suitable for characterization of re-epithelialization is validated and explored in this study. It exploits scale-invariance to enable fitting of the epidermal skin layer only. Monte Carlo simulations indicate that the fitted layer transmittance and reflectance spectra are unique, and that there exists an infinite number of coupled parameter solutions. The method is used to explain the optical behavior of and detect re-epithelialization in an in vitro wound model.
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19
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Hernández-Quintanar L, Fabila-Bustos DA, Hernández-Chávez M, Valor A, de la Rosa JM, Stolik S. Fiber-optic pulseoximeter for local oxygen saturation determination using a Monte Carlo multi-layer model for calibration. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2020; 187:105237. [PMID: 31790944 DOI: 10.1016/j.cmpb.2019.105237] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 09/28/2019] [Accepted: 11/20/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND OBJECTIVE Local tissue oxygenation determines the relationship between the supply and the demand for oxygen by the tissue and it is an important indicator of the physiological or pathological condition of the tissue. Moreover, some therapeutic methods strongly depend on the oxygen content of the tissue. In photodynamic therapy, when molecular oxygen is present, the irradiation of the photosensitizer with light triggers the generation of reactive oxygen species that kill the target diseased cells within the treated tissue. To ensure the best possible therapy response, the tissue must be well oxygenated; hence, oxygen concentration measurement becomes a decisive factor. In this work, the design, construction and calibration of a module to locally measure the blood oxygen saturation in tissue is presented. METHODS The system is built using a red (660-nm) and an infrared (940-nm) light emitting diodes as light sources, a photodiode as a detector, and a homemade handheld fiber optic-based reflectance pulse oximetry sensor. In addition, the developed sensor was modeled by means of multilayered Monte Carlo simulations, to study its behavior when used in different thickness and melanin content skin. RESULTS From the simulation reflectance values, the oxygen saturation calibration curves considering different melanin concentrations and skin thicknesses were obtained for two different skin models, one comprising three skin layers and the second, assuming seven different layers for the skin. A comparison of the performances of the developed pulse oximeter sensor with a commercial one is also presented. CONCLUSIONS A new pulseoximeter for the measurement of local oxygenation in tissue was developed. Its calibration strongly depends on the site of measurement due to the influence of tissue thickness, vascularization, and melanin content. A three-layer skin model is proved to be suitable for the calibration of the pulseoximeter in thin and medium thickness skin.
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Affiliation(s)
- Luis Hernández-Quintanar
- Laboratorio de Biofotónica, ESIME ZAC, Instituto Politécnico Nacional, Ciudad de México, 07738, Mexico; Laboratorio de Espectroscopía, UPIIH, Instituto Politécnico Nacional, Ciudad del Conocimiento y la Cultura, San Agustín Tlaxiaca, Hidalgo, 42162, Mexico
| | - Diego A Fabila-Bustos
- Laboratorio de Biofotónica, ESIME ZAC, Instituto Politécnico Nacional, Ciudad de México, 07738, Mexico; Laboratorio de Espectroscopía, UPIIH, Instituto Politécnico Nacional, Ciudad del Conocimiento y la Cultura, San Agustín Tlaxiaca, Hidalgo, 42162, Mexico
| | - Macaria Hernández-Chávez
- Laboratorio de Espectroscopía, UPIIH, Instituto Politécnico Nacional, Ciudad del Conocimiento y la Cultura, San Agustín Tlaxiaca, Hidalgo, 42162, Mexico
| | - Alma Valor
- Laboratorio de Biofotónica, ESIME ZAC, Instituto Politécnico Nacional, Ciudad de México, 07738, Mexico
| | - José M de la Rosa
- Laboratorio de Biofotónica, ESIME ZAC, Instituto Politécnico Nacional, Ciudad de México, 07738, Mexico
| | - Suren Stolik
- Laboratorio de Biofotónica, ESIME ZAC, Instituto Politécnico Nacional, Ciudad de México, 07738, Mexico.
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Estimation of Biological Parameters of Cutaneous Ulcers Caused by Leishmaniasis in an Animal Model Using Diffuse Reflectance Spectroscopy. SENSORS 2019; 19:s19214674. [PMID: 31661834 PMCID: PMC6864670 DOI: 10.3390/s19214674] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 10/22/2019] [Accepted: 10/24/2019] [Indexed: 11/30/2022]
Abstract
Cutaneous leishmaniasis (CL) is a neglected tropical disease that requires novel tools for its understanding, diagnosis, and treatment follow-up. In the cases of other cutaneous pathologies, such as cancer or cutaneous ulcers due to diabetes, optical diffuse reflectance-based tools and methods are widely used for the investigation of those illnesses. These types of tools and methods offer the possibility to develop portable diagnosis and treatment follow-up systems. In this article, we propose the use of a three-layer diffuse reflectance model for the study of the formation of cutaneous ulcers caused by CL. The proposed model together with an inverse-modeling procedure were used in the evaluation of diffuse-reflectance spectral signatures acquired from cutaneous ulcers formed in the dorsal area of 21 golden hamsters inoculated with Leishmanisis braziliensis. As result, the quantification of the model’s variables related to the main biological parameters of skin were obtained, such as: diameter and volumetric fraction of keratinocytes, collagen; volumetric fraction of hemoglobin, and oxygen saturation. Those parameters show statistically significant differences among the different stages of the CL ulcer formation. We found that these differences are coherent with histopathological manifestations reported in the literature for the main phases of CL formation.
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21
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Extended-wavelength diffuse reflectance spectroscopy with a machine-learning method for in vivo tissue classification. PLoS One 2019; 14:e0223682. [PMID: 31600296 PMCID: PMC6786558 DOI: 10.1371/journal.pone.0223682] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 09/25/2019] [Indexed: 01/04/2023] Open
Abstract
OBJECTIVES An extended-wavelength diffuse reflectance spectroscopy (EWDRS) technique was evaluated for its ability to differentiate between and classify different skin and tissue types in an in vivo pig model. MATERIALS AND METHODS EWDRS recordings (450-1550 nm) were made on skin with different degrees of pigmentation as well as on the pig snout and tongue. The recordings were used to train a support vector machine to identify and classify the different skin and tissue types. RESULTS The resulting EWDRS curves for each skin and tissue type had a unique profile. The support vector machine was able to classify each skin and tissue type with an overall accuracy of 98.2%. The sensitivity and specificity were between 96.4 and 100.0% for all skin and tissue types. CONCLUSION EWDRS can be used in vivo to differentiate between different skin and tissue types with good accuracy. Further development of the technique may potentially lead to a novel diagnostic tool for e.g. non-invasive tumor margin delineation.
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Validation of an Inverse Fitting Method of Diffuse Reflectance Spectroscopy to Quantify Multi-Layered Skin Optical Properties. PHOTONICS 2019. [DOI: 10.3390/photonics6020061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Skin consists of epidermis and dermis layers that have distinct optical properties. The quantification of skin optical properties is commonly achieved by modeling photon propagation in tissue using Monte Carlo (MC) simulations and iteratively fitting experimentally measured diffuse reflectance spectra. In order to speed up the inverse fitting process, time-consuming MC simulations have been replaced by artificial neural networks to quickly calculate reflectance spectra given tissue geometric and optical parameters. In this study the skin was modeled to consist of three layers and different scattering properties of the layers were considered. A new inverse fitting procedure was proposed to improve the extraction of chromophore-related information in the skin, including the hemoglobin concentration, oxygen saturation and melanin absorption. The performance of the new inverse fitting procedure was evaluated on 40 sets of simulated spectra. The results showed that the fitting procedure without knowing the epidermis thickness extracted chromophore information with accuracy similar to or better than fitting with known epidermis thickness, which is advantageous for practical applications due to simpler and more cost-effective instruments. In addition, the melanin volume fraction multiplied by the thickness of the melanin-containing epidermis layer was estimated more accurately than the melanin volume fraction itself. This product has the potential to provide a quantitative indicator of melanin absorption in the skin. In-vivo cuff occlusion experiments were conducted and skin optical properties extracted from the experiments were comparable to the results of previously reported in vivo studies. The results of the current study demonstrated the applicability of the proposed method to quantify the optical properties related to major chromophores in the skin, as well as scattering coefficients of the dermis. Therefore, it has the potential to be a useful tool for quantifying skin optical properties in vivo.
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23
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Afshari A, Keil M, Lyssikatos C, Belyavskaya E, Valdés N, Chowdhry FA, Parsa K, Ardeshirpour Y, Pursley R, Khare S, Kainerstorfer JM, Chittiboina P, Lodish MB, Mazzuchi TA, Gandjbakhche AH, Stratakis CA. Optical Imaging Technology: A Useful Tool to Identify Remission in Cushing Disease After Surgery. Horm Metab Res 2019; 51:120-126. [PMID: 30602178 PMCID: PMC6753582 DOI: 10.1055/a-0801-8917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We recently reported the use of optical imaging technology to quantify facial plethora in endogenous Cushing syndrome (CS). In the present study, we studied a larger cohort of patients with Cushing disease (CD) and examined water content fraction as well as blood volume fraction as bio-optic markers for determining the efficacy of this methodology as a predictor of lasting remission after surgery for CS. We imaged 49 patients before and after transsphenoidal surgery (TSS) for Cushing disease (CD); 22 patients were also seen at 3-6 months, and 13 patients 12 months post-operatively. On all patients, we used multi-spectral imaging (MSI) to evaluate hemodynamic distributions as well as water content at a specific area of the face. We found a decrease in blood volume fraction after vs. before surgical treatment in the tested facial area in 37 of the 40 patients, as determined with biochemical markers (p<0.001). All patients that were followed up for up to 12 months showed the same decrease from preoperative values and they remained in remission from CD. We conclude that MSI can be used for the evaluation of remission from CD, at least in the immediate post-operative period and up to one year after surgery. The use of this technology can supplement biochemical and other testing for the evaluation of the various treatment modalities available for patients with CD.
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Affiliation(s)
- Ali Afshari
- Section on Analytical and Functional Biophotonics, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Margaret Keil
- Section on Endocrinology and Genetics Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Charalampos Lyssikatos
- Section on Endocrinology and Genetics Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Elena Belyavskaya
- Section on Endocrinology and Genetics Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Nuria Valdés
- Service of Endocrinology and Nutrition, Hospital Universitario Central de Asturias, Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain
| | - Fatima A. Chowdhry
- Section on Analytical and Functional Biophotonics, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Kian Parsa
- Section on Analytical and Functional Biophotonics, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Yasaman Ardeshirpour
- Section on Analytical and Functional Biophotonics, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Randall Pursley
- Section on Signal Processing & Instrumentation, Computational Biosciences and Engineering Laboratory, Office of Intramural Research (OIR), Center for Information Technology (CIT), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Siddharth Khare
- Section on Analytical and Functional Biophotonics, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Jana M. Kainerstorfer
- Assistant Professor of Biomedical Engineering, College of Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Prashant Chittiboina
- Section on Endocrinology and Genetics Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Maya B. Lodish
- Section on Endocrinology and Genetics Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Thomas A. Mazzuchi
- Professor and Department Chair of Engineering Management $ System Engineering Department, Engineering and Applied Science School, George Washington University, Washington, DC, USA
| | - Amir H. Gandjbakhche
- Section on Analytical and Functional Biophotonics, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - Constantine A. Stratakis
- Section on Endocrinology and Genetics Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland, USA
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Epidermal Fluence Threshold Determination by Real-Time Melanin Measurements. Dermatol Surg 2018; 44:1427-1436. [PMID: 30020097 DOI: 10.1097/dss.0000000000001606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND OBJECTIVE Epidermal preservation is essential during laser treatment for vascular, hair, and benign pigment dyschromias. Epidermal tolerance is determined by epidermal melanin content, fluence, pulse width, wavelength, skin cooling, and spot size. The authors' objective was to determine the maximum epidermal tolerance for the long-pulse alexandrite 755 nm and the long-pulse neodymium-doped yttrium aluminum garnet (Nd:YAG) 1064-nm lasers for varying epidermal melanin content. MATERIALS AND METHODS Skin melanin measurements were performed at the test sites with a melanin reader, and 0.5 to 1 second of refrigerated air precooled the skin. Then, alexandrite and Nd:YAG laser test spots of 5 to 18 mm were delivered in a series of ascending fluences using 5-, 20-, and 50-ms pulse widths. Skin response at 24 to 48 and 96 hours was scored from 0 to 15 varying from "no reaction" to "severe scabbing." RESULTS Alexandrite laser, mean threshold fluences increased by a factor of 1.2 increasing from 5 to 20 ms, and by a factor of 1.4 increasing from 5 to 50 ms, among subjects with a melanin index (MI) from 9 to 25 (Fitzpatrick skin phototype I-III). The Nd:YAG fluence to reach epidermal tolerance was 6X the fluence with the alexandrite laser for the same MI in subjects with MI 26 to 35. CONCLUSION Epidermal melanin measurements are quantitative and objective, therefore, improving treatment setting determination by decreasing the risk of overtreatment or undertreatment.
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Hsieh HP, Ko FH, Sung KB. Hybrid method to estimate two-layered superficial tissue optical properties from simulated data of diffuse reflectance spectroscopy. APPLIED OPTICS 2018; 57:3038-3046. [PMID: 29714335 DOI: 10.1364/ao.57.003038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 03/12/2018] [Indexed: 06/08/2023]
Abstract
An iterative curve fitting method has been applied in both simulation [J. Biomed. Opt.17, 107003 (2012)JBOPFO1083-366810.1117/1.JBO.17.10.107003] and phantom [J. Biomed. Opt.19, 077002 (2014)JBOPFO1083-366810.1117/1.JBO.19.7.077002] studies to accurately extract optical properties and the top layer thickness of a two-layered superficial tissue model from diffuse reflectance spectroscopy (DRS) data. This paper describes a hybrid two-step parameter estimation procedure to address two main issues of the previous method, including (1) high computational intensity and (2) converging to local minima. The parameter estimation procedure contained a novel initial estimation step to obtain an initial guess, which was used by a subsequent iterative fitting step to optimize the parameter estimation. A lookup table was used in both steps to quickly obtain reflectance spectra and reduce computational intensity. On simulated DRS data, the proposed parameter estimation procedure achieved high estimation accuracy and a 95% reduction of computational time compared to previous studies. Furthermore, the proposed initial estimation step led to better convergence of the following fitting step. Strategies used in the proposed procedure could benefit both the modeling and experimental data processing of not only DRS but also related approaches such as near-infrared spectroscopy.
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Tsui SY, Wang CY, Huang TH, Sung KB. Modelling spatially-resolved diffuse reflectance spectra of a multi-layered skin model by artificial neural networks trained with Monte Carlo simulations. BIOMEDICAL OPTICS EXPRESS 2018; 9:1531-1544. [PMID: 29675300 PMCID: PMC5905904 DOI: 10.1364/boe.9.001531] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 02/21/2018] [Accepted: 03/01/2018] [Indexed: 05/13/2023]
Abstract
A robust modelling method was proposed to extract chromophore information in multi-layered skin tissue with spatially-resolved diffuse reflectance spectroscopy. Artificial neural network models trained with a pre-simulated database were first built to map geometric and optical parameters into diffuse reflectance spectra. Nine fitting parameters including chromophore concentrations and oxygen saturation were then determined by solving the inverse problem of fitting spectral measurements from three different parts of the skin. Compared to the Monte Carlo simulation accelerated by a graphics processing unit, the proposed modelling method not only reduced the computation time, but also achieved a better fitting performance.
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Affiliation(s)
- Sheng-Yang Tsui
- Department of Electrical Engineering, National Taiwan University, Taipei,
Taiwan
| | - Chiao-Yi Wang
- Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei,
Taiwan
| | - Tsan-Hsueh Huang
- Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei,
Taiwan
| | - Kung-Bin Sung
- Department of Electrical Engineering, National Taiwan University, Taipei,
Taiwan
- Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei,
Taiwan
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Kanakaraj BN, Narayanan Unni S. Model-based quantitative optical biopsy in multilayer in vitro soft tissue models for whole field assessment of nonmelanoma skin cancer. J Med Imaging (Bellingham) 2018; 5:014506. [PMID: 29594182 DOI: 10.1117/1.jmi.5.1.014506] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 02/20/2018] [Indexed: 11/14/2022] Open
Abstract
Optical techniques such as fluorescence and diffuse reflectance spectroscopy are proven to have the potential to provide tissue discrimination during the development of malignancies and hence treated as potential tools for noninvasive optical biopsy in clinical diagnostics. Quantitative optical biopsy is challenging and hence the majority of the existing strategies are based on a qualitative assessment of the concerned tissue. Light-tissue interaction models as well as precise optical phantoms can greatly help in the former and here we present a pilot study to assess the optical properties of a multilayer tissue-specific optical phantom with the help of a database generated using multilayer-Monte Carlo (MCML) models. A set of optical models mimicking the properties of actual and diseased conditions of tissues associated with nonmelanoma skin cancer (NMSC) were devised and MCML simulations of fluorescence and diffuse reflectance were performed on these models to generate the spectral signature of identified biomarkers of NMSC such as hemoglobin, flavin adenine dinucleotide, and collagen. A model library was generated and with the extracted features from modeled spectra, classification of normal and NMSC conditions were tested using the [Formula: see text]-nearest neighbor (KNN) classifier. Using an in-house assembled scan-based automated bimodal spectral imaging system with reflectance and fluorescence modalities of operation, a layered, thin, tissue equivalent phantom, fabricated with controlled optical properties mimicking normal and NMSC conditions were tested. The spectral signatures corresponding to the NMSC biomarkers were acquired from this phantom and extracted features from the spectra were tested using the KNN classifier and classification accuracy of 100% was achieved. For further quantitative analysis, the experimental and simulated spectra were compared with respect to the light intensity at the emission peak or absorption dips, spectral line width, and average intensity over a range of wavelength of interest and observed to be analogous within specified and systematic error limits. This methodology is expected to give a better quantitative approach for estimation of tissue properties by correlating the experimental and simulated data.
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Affiliation(s)
- Bala Nivetha Kanakaraj
- Indian Institute of Technology Madras, Biophotonics Laboratory, Department of Applied Mechanics, Chennai, Tamil Nadu, India
| | - Sujatha Narayanan Unni
- Indian Institute of Technology Madras, Biophotonics Laboratory, Department of Applied Mechanics, Chennai, Tamil Nadu, India
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Reis ZSN, Vitral GLN, de Souza IMF, Rego MAS, Guimaraes RN. Newborn skin reflection: Proof of concept for a new approach for predicting gestational age at birth. A cross-sectional study. PLoS One 2017; 12:e0184734. [PMID: 28931040 PMCID: PMC5607181 DOI: 10.1371/journal.pone.0184734] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 08/30/2017] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Current methods to assess the gestational age during prenatal care or at birth are a global challenge. Disadvantages, such as low accessibility, high costs, and imprecision of clinical tests and ultrasonography measurements, may compromise health decisions at birth, based on the gestational age. Newborns' organs and tissues can indirectly indicate their physical maturity, and we hypothesized that evolutionary changes in their skin, detected using an optoelectronic device meter, may aid in estimating the gestational age. This study analyzed the feasibility of using newborn skin reflectance to estimate the gestational age at birth noninvasively. METHODS AND FINDINGS A cross-sectional study evaluated the skin reflectance of selected infants, preferably premature, at birth. The first-trimester ultrasound was the reference for gestational age. A prototype of a new noninvasive optoelectronic device measured the backscattering of light from the skin, using a light emitting diode at wavelengths of 470 nm, 575 nm, and 630 nm. Univariate and multivariate regression analysis models were employed to predict gestational age, combining skin reflectance with clinical variables for gestational age estimation. The gestational age at birth of 115 newborns from 24.1 to 41.8 weeks of gestation correlated with the light at 630 nm wavelength reflectance 3.3 mm/6.5 mm ratio distant of the sensor, at the forearm and sole (Pearson's correlation = 0.505, P < 0.001 and 0.710, P < 0.001, respectively). The best-combined variables to predict the gold standard gestational age at birth was the skin reflectance at wavelengths of 630 nm and 470 nm in combination with birth weight, phototherapy, and adjusted to include incubator stay, and sex (R2 = 0.828, P < 0.001). The main limitation of the study is that it was very specific to the premature population we studied and needs to be studied in a broader spectrum of newborns. CONCLUSIONS A novel automated skin reflectometer device, in combination with clinical variables, was able to predict the gestational age and could be useful when the information is in doubt or is unknown. Multivariable predictive models associated the skin reflectance with easy to obtain clinical parameters, at the birth scenario. External validation needs to be proven in an actual population with the real incidence of premature infants.
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Affiliation(s)
- Zilma Silveira Nogueira Reis
- Center of Health Informatics, Faculty of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Postgraduation Program of Women’s Health, Faculty of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Department of Gynecology and Obstetrics, Faculty of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- * E-mail:
| | - Gabriela Luiza Nogueira Vitral
- Postgraduation Program of Women’s Health, Faculty of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | | | - Maria Albertina Santiago Rego
- Department of Pediatrics, Faculty of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Rodney Nascimento Guimaraes
- Postgraduation Program of Women’s Health, Faculty of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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Nivetha KB, Sujatha N. Development of thin skin mimicking bilayer solid tissue phantoms for optical spectroscopic studies. BIOMEDICAL OPTICS EXPRESS 2017; 8:3198-3212. [PMID: 28717562 PMCID: PMC5508823 DOI: 10.1364/boe.8.003198] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 05/15/2017] [Accepted: 05/19/2017] [Indexed: 05/31/2023]
Abstract
In vivo spectroscopic measurements have the proven potential to provide important insight about the changes in tissue during the development of malignancies and thus help to diagnose tissue pathologies. Extraction of intrinsic data in the presence of varying amounts of scatterers and absorbers offers great challenges in the development of such techniques to the clinical level. Fabrication of optical phantoms, tailored to the biochemical as well as morphological features of the target tissue, can help to generate a spectral database for a given optical spectral measurement system. Such databases, along with appropriate pattern matching algorithms, could be integrated with in vivo measurements for any desired quantitative analysis of the target tissue. This paper addresses the fabrication of such soft, photo stable, thin bilayer phantoms, mimicking skin tissue in layer dimensions and optical properties. The performance evaluation of the fabricated set of phantoms is carried out using a portable fluorescence spectral measurement system. The alterations in flavin adenine dinucleotide (FAD)-a tissue fluorophore that provides important information about dysplastic progressions in tissues associated with cancer development based on changes in emission spectra-fluorescence with varied concentrations of absorbers and scatterers present in the phantom are analyzed and the results are presented. Alterations in the emission intensity, shift in emission wavelength and broadening of the emission spectrum were found to be potential markers in the assessment of biochemical changes that occur during the progression of dysplasia.
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Affiliation(s)
- K Bala Nivetha
- Biophotonics Lab, Department of Applied Mechanics, Indian Institute of Technology Madras, Chennai-600036, India
| | - N Sujatha
- Biophotonics Lab, Department of Applied Mechanics, Indian Institute of Technology Madras, Chennai-600036, India
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30
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Schwarz M, Soliman D, Omar M, Buehler A, Ovsepian SV, Aguirre J, Ntziachristos V. Optoacoustic Dermoscopy of the Human Skin: Tuning Excitation Energy for Optimal Detection Bandwidth With Fast and Deep Imaging in vivo. IEEE TRANSACTIONS ON MEDICAL IMAGING 2017; 36:1287-1296. [PMID: 28278460 DOI: 10.1109/tmi.2017.2664142] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Optoacoustic (photoacoustic) dermoscopy offers two principal advantages over conventional optical imaging applied in dermatology. First, it yields high-resolution cross-sectional images of the skin at depths not accessible to other non-invasive optical imaging methods. Second, by resolving absorption spectra at multiple wavelengths, it enables label-free 3D visualization of morphological and functional features. However, the relation of pulse energy to generated bandwidth and imaging depth remains poorly defined. In this paper, we apply computer models to investigate the optoacoustic frequency response generated by simulated skin. We relate our simulation results to experimental measurements of the detection bandwidth as a function of optical excitation energy in phantoms and human skin. Using raster-scan optoacoustic mesoscopy, we further compare the performance of two broadband ultrasonic detectors (a bandwidth of 20-180 and 10-90MHz) in acquiring optoacoustic readouts. Based on the findings of this paper, we propose energy ranges required for skin imaging with considerations of laser safety standards.
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31
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Feng W, Shi R, Zhang C, Yu T, Zhu D. Lookup-table-based inverse model for mapping oxygen concentration of cutaneous microvessels using hyperspectral imaging. OPTICS EXPRESS 2017; 25:3481-3495. [PMID: 28241562 DOI: 10.1364/oe.25.003481] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Hyperspectral imaging combining with skin optical clearing technique provides a possible way to non-invasively monitor hemodynamics of cutaneous microvessels. In order to estimate microvascular blood oxygen saturation, in this work, a lookup-table-based inverse model was developed to extract the microvascular optical and physiological properties using hyperspectral analysis. This approach showed a higher fitting degree than currently existing hyperspectral analysis methods (i.e. multiple linear regression and non-negative least square fit) in estimating blood oxygen saturation. Hypoxic stimulation experiment showed that calculated results were in accordance with physiological changes, and the relative changes of estimated oxygen saturation indicated this method appeared to be more sensitive to blood oxygen fluctuation. And a simulated blood model was used for verification here, indicating this method also showed a good accuracy in determining oxygen saturation from the simulated spectra.
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Jung DS, Crowe JA, Birchall JP, Somekh MG, See CW. Anti-confocal assessment of middle ear inflammation. BIOMEDICAL OPTICS EXPRESS 2017; 8:230-242. [PMID: 28101414 PMCID: PMC5231295 DOI: 10.1364/boe.8.000230] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 11/03/2016] [Accepted: 11/04/2016] [Indexed: 06/06/2023]
Abstract
To improve the diagnostic prediction of recurrence of otitis media with effusion after surgery, an anti-confocal system combined with spectroscopic measurements is proposed to reject unwanted signals from the eardrum and assess the blood content. The anti-confocal system was experimentally evaluated on both optical middle ear phantom and human skin. Results showed effective rejection of signals from the eardrum using a central stop replacing the confocal pinhole, while still detecting signals from the middle ear mucosa. The system is sensitive to changes in blood content, but scattering and absorption characteristics of the eardrum can distort the measurement. Confocal detection of eardrum properties was shown to be a promising approach to correct measurements.
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Affiliation(s)
- David S. Jung
- National Institute for Health Research (NIHR) Nottingham Hearing Biomedical Research Unit, 113 The Ropewalk, Nottingham, NG1 5DU,
UK
- Department of Electrical and Electronic Engineering, University of Nottingham, University Park, Nottingham, NG7 2RD,
UK
| | - John A. Crowe
- Department of Electrical and Electronic Engineering, University of Nottingham, University Park, Nottingham, NG7 2RD,
UK
| | - John P. Birchall
- National Institute for Health Research (NIHR) Nottingham Hearing Biomedical Research Unit, 113 The Ropewalk, Nottingham, NG1 5DU,
UK
- Otology and Hearing group, Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, NG7 2UH,
UK
| | - Michael G. Somekh
- Department of Electrical and Electronic Engineering, University of Nottingham, University Park, Nottingham, NG7 2RD,
UK
- Department of Electronic and Information Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong,
China
| | - Chung W. See
- Department of Electrical and Electronic Engineering, University of Nottingham, University Park, Nottingham, NG7 2RD,
UK
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33
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Huang PY, Chien CY, Sheu CR, Chen YW, Tseng SH. Light distribution modulated diffuse reflectance spectroscopy. BIOMEDICAL OPTICS EXPRESS 2016; 7:2118-2129. [PMID: 27375931 PMCID: PMC4918569 DOI: 10.1364/boe.7.002118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 05/03/2016] [Indexed: 06/06/2023]
Abstract
Typically, a diffuse reflectance spectroscopy (DRS) system employing a continuous wave light source would need to acquire diffuse reflectances measured at multiple source-detector separations for determining the absorption and reduced scattering coefficients of turbid samples. This results in a multi-fiber probe structure and an indefinite probing depth. Here we present a novel DRS method that can utilize a few diffuse reflectances measured at one source-detector separation for recovering the optical properties of samples. The core of innovation is a liquid crystal (LC) cell whose scattering property can be modulated by the bias voltage. By placing the LC cell between the light source and the sample, the spatial distribution of light in the sample can be varied as the scattering property of the LC cell modulated by the bias voltage, and this would induce intensity variation of the collected diffuse reflectance. From a series of Monte Carlo simulations and phantom measurements, we found that this new light distribution modulated DRS (LDM DRS) system was capable of accurately recover the absorption and scattering coefficients of turbid samples and its probing depth only varied by less than 3% over the full bias voltage variation range. Our results suggest that this LDM DRS platform could be developed to various low-cost, efficient, and compact systems for in-vivo superficial tissue investigation.
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Affiliation(s)
- Pin-Yuan Huang
- Department of Photonics, National Cheng-Kung University, Tainan, 701, Taiwan
| | - Chun-Yu Chien
- Department of Photonics, National Cheng-Kung University, Tainan, 701, Taiwan
| | - Chia-Rong Sheu
- Department of Photonics, National Cheng-Kung University, Tainan, 701, Taiwan
| | - Yu-Wen Chen
- Department of Photonics, National Cheng-Kung University, Tainan, 701, Taiwan
| | - Sheng-Hao Tseng
- Department of Photonics, National Cheng-Kung University, Tainan, 701, Taiwan
- Advanced Optoelectronic Technology Center, National Cheng-Kung University, Tainan, 701, Taiwan
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Transcutaneous Immunization Using Nano-sized Drug Carriers. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2016. [DOI: 10.1007/978-1-4939-3121-7_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
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Radrich K, Ntziachristos V. Quantitative multi-spectral oxygen saturation measurements independent of tissue optical properties. JOURNAL OF BIOPHOTONICS 2016; 9:83-99. [PMID: 25765987 DOI: 10.1002/jbio.201400092] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 10/19/2014] [Accepted: 01/26/2015] [Indexed: 06/04/2023]
Abstract
Imaging of tissue oxygenation is important in several applications associated with patient care. Optical sensing is commonly applied for assessing oxygen saturation but is often restricted to local measurements or else it requires spectral and spatial information at the expense of time. Many methods proposed so far require assumptions on the properties of measured tissue. In this study we investigated a computational method that uses only multispectral information and quantitatively computes tissue oxygen saturation independently of tissue optical properties. The method is based on linear transformations of measurements in three isosbestic points. We investigated the ideal isosbestic point combination out of six isosbestic points available for measurement in the visible and near-infrared region that enable accurate oxygen saturation computation. We demonstrate this method on controlled tissue mimicking phantoms having different optical properties and validated the measurements using a gas analyzer. A mean error of 2.9 ± 2.8% O2 Sat was achieved. Finally, we performed pilot studies in tissues in-vivo by measuring dynamic changes in fingers subjected to vascular occlusion, the vasculature of mouse ears and exposed mouse organs.
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Affiliation(s)
- Karin Radrich
- Technische Universität München, Chair for Biological Imaging, Munich, Germany
- Helmholtz Zentrum München, Institute for Biological and Medical Imaging, Neuherberg, Germany
| | - Vasilis Ntziachristos
- Technische Universität München, Chair for Biological Imaging, Munich, Germany
- Helmholtz Zentrum München, Institute for Biological and Medical Imaging, Neuherberg, Germany
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Afshari A, Ardeshirpour Y, Lodish MB, Gourgari E, Sinaii N, Keil M, Belyavskaya E, Lyssikatos C, Chowdhry FA, Chernomordik V, Anderson AA, Mazzuchi TA, Gandjbakhche A, Stratakis CA. Facial Plethora: Modern Technology for Quantifying an Ancient Clinical Sign and Its Use in Cushing Syndrome. J Clin Endocrinol Metab 2015; 100:3928-33. [PMID: 26301943 PMCID: PMC4596033 DOI: 10.1210/jc.2015-2497] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Facial plethora is a clinical sign described since ancient times for a variety of diseases. In the 19th century, it was linked to increased blood volume or flow, but this has never been proven. Facial plethora is also one of the earliest described clinical features of Cushing's syndrome (CS). OBJECTIVE This study aimed to quantify facial plethora changes in CS as an early assessment of cure after surgery using noninvasive near-infrared multispectral imaging (MSI). DESIGN The longitudinal cohort study was initiated in August 2012 and completed in August 2014. SETTING Clinical research hospital, National Institutes of Health. PATIENTS Thirty-four of the 38 patients who received surgical treatment for CS under protocol 97CH0076 during this period were included. INTERVENTION(S) MSI was performed on the right cheek of patients before surgery and 4.9 ± 3.1 days afterward. MAIN OUTCOME MEASURE(S) Average blood volume fraction as measured by MSI and serum cortisol. RESULTS All but four of the 28 patients (86%) who were assessed as cured by postoperative plasma cortisol measurements of < 3 μg/dL showed a decrease in blood volume fraction (17.7 ± 0.03 vs 15.8 ± 0.03%; P = .0019), whereas an increase was seen in patients with persistent CS (18.5 ± 0.03 vs 21.4 ± 0.04%; P = .0017). Change in blood volume fraction before and after surgery was correlated with postoperative cortisol (rs = 0.58; P = .0003). CONCLUSIONS Clinical data obtained from 34 patients indicate that a decrease in facial plethora after surgery, as evidenced by a decrease in blood volume fraction, is correlated with CS outcome. This novel technology for the first time identified a physiological mechanism associated with an ancient clinical sign. Furthermore, as a proof of principle, MSI is a promising early marker of cure in patients with CS that complements biochemical and clinical data.
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Affiliation(s)
- Ali Afshari
- Section on Analytical and Functional Biophotonics (A.A., Y.A., F.A.C., V.C., A.A.A., A.G.), and Program on Developmental Endocrinology and Genetics (M.B.L., E.G, M.K., E.B., C.L., C.A.S.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Biostatistics and Clinical Epidemiology Service (N.S.), Clinical Research Center, National Institutes of Health, Bethesda, Maryland 20892; and George Washington University Department of System Engineering (T.A.M.), Washington, DC 20052
| | - Yasaman Ardeshirpour
- Section on Analytical and Functional Biophotonics (A.A., Y.A., F.A.C., V.C., A.A.A., A.G.), and Program on Developmental Endocrinology and Genetics (M.B.L., E.G, M.K., E.B., C.L., C.A.S.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Biostatistics and Clinical Epidemiology Service (N.S.), Clinical Research Center, National Institutes of Health, Bethesda, Maryland 20892; and George Washington University Department of System Engineering (T.A.M.), Washington, DC 20052
| | - Maya Beth Lodish
- Section on Analytical and Functional Biophotonics (A.A., Y.A., F.A.C., V.C., A.A.A., A.G.), and Program on Developmental Endocrinology and Genetics (M.B.L., E.G, M.K., E.B., C.L., C.A.S.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Biostatistics and Clinical Epidemiology Service (N.S.), Clinical Research Center, National Institutes of Health, Bethesda, Maryland 20892; and George Washington University Department of System Engineering (T.A.M.), Washington, DC 20052
| | - Evgenia Gourgari
- Section on Analytical and Functional Biophotonics (A.A., Y.A., F.A.C., V.C., A.A.A., A.G.), and Program on Developmental Endocrinology and Genetics (M.B.L., E.G, M.K., E.B., C.L., C.A.S.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Biostatistics and Clinical Epidemiology Service (N.S.), Clinical Research Center, National Institutes of Health, Bethesda, Maryland 20892; and George Washington University Department of System Engineering (T.A.M.), Washington, DC 20052
| | - Ninet Sinaii
- Section on Analytical and Functional Biophotonics (A.A., Y.A., F.A.C., V.C., A.A.A., A.G.), and Program on Developmental Endocrinology and Genetics (M.B.L., E.G, M.K., E.B., C.L., C.A.S.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Biostatistics and Clinical Epidemiology Service (N.S.), Clinical Research Center, National Institutes of Health, Bethesda, Maryland 20892; and George Washington University Department of System Engineering (T.A.M.), Washington, DC 20052
| | - Margaret Keil
- Section on Analytical and Functional Biophotonics (A.A., Y.A., F.A.C., V.C., A.A.A., A.G.), and Program on Developmental Endocrinology and Genetics (M.B.L., E.G, M.K., E.B., C.L., C.A.S.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Biostatistics and Clinical Epidemiology Service (N.S.), Clinical Research Center, National Institutes of Health, Bethesda, Maryland 20892; and George Washington University Department of System Engineering (T.A.M.), Washington, DC 20052
| | - Elena Belyavskaya
- Section on Analytical and Functional Biophotonics (A.A., Y.A., F.A.C., V.C., A.A.A., A.G.), and Program on Developmental Endocrinology and Genetics (M.B.L., E.G, M.K., E.B., C.L., C.A.S.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Biostatistics and Clinical Epidemiology Service (N.S.), Clinical Research Center, National Institutes of Health, Bethesda, Maryland 20892; and George Washington University Department of System Engineering (T.A.M.), Washington, DC 20052
| | - Charalampos Lyssikatos
- Section on Analytical and Functional Biophotonics (A.A., Y.A., F.A.C., V.C., A.A.A., A.G.), and Program on Developmental Endocrinology and Genetics (M.B.L., E.G, M.K., E.B., C.L., C.A.S.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Biostatistics and Clinical Epidemiology Service (N.S.), Clinical Research Center, National Institutes of Health, Bethesda, Maryland 20892; and George Washington University Department of System Engineering (T.A.M.), Washington, DC 20052
| | - Fatima A Chowdhry
- Section on Analytical and Functional Biophotonics (A.A., Y.A., F.A.C., V.C., A.A.A., A.G.), and Program on Developmental Endocrinology and Genetics (M.B.L., E.G, M.K., E.B., C.L., C.A.S.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Biostatistics and Clinical Epidemiology Service (N.S.), Clinical Research Center, National Institutes of Health, Bethesda, Maryland 20892; and George Washington University Department of System Engineering (T.A.M.), Washington, DC 20052
| | - Victor Chernomordik
- Section on Analytical and Functional Biophotonics (A.A., Y.A., F.A.C., V.C., A.A.A., A.G.), and Program on Developmental Endocrinology and Genetics (M.B.L., E.G, M.K., E.B., C.L., C.A.S.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Biostatistics and Clinical Epidemiology Service (N.S.), Clinical Research Center, National Institutes of Health, Bethesda, Maryland 20892; and George Washington University Department of System Engineering (T.A.M.), Washington, DC 20052
| | - Afrouz A Anderson
- Section on Analytical and Functional Biophotonics (A.A., Y.A., F.A.C., V.C., A.A.A., A.G.), and Program on Developmental Endocrinology and Genetics (M.B.L., E.G, M.K., E.B., C.L., C.A.S.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Biostatistics and Clinical Epidemiology Service (N.S.), Clinical Research Center, National Institutes of Health, Bethesda, Maryland 20892; and George Washington University Department of System Engineering (T.A.M.), Washington, DC 20052
| | - Thomas A Mazzuchi
- Section on Analytical and Functional Biophotonics (A.A., Y.A., F.A.C., V.C., A.A.A., A.G.), and Program on Developmental Endocrinology and Genetics (M.B.L., E.G, M.K., E.B., C.L., C.A.S.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Biostatistics and Clinical Epidemiology Service (N.S.), Clinical Research Center, National Institutes of Health, Bethesda, Maryland 20892; and George Washington University Department of System Engineering (T.A.M.), Washington, DC 20052
| | - Amir Gandjbakhche
- Section on Analytical and Functional Biophotonics (A.A., Y.A., F.A.C., V.C., A.A.A., A.G.), and Program on Developmental Endocrinology and Genetics (M.B.L., E.G, M.K., E.B., C.L., C.A.S.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Biostatistics and Clinical Epidemiology Service (N.S.), Clinical Research Center, National Institutes of Health, Bethesda, Maryland 20892; and George Washington University Department of System Engineering (T.A.M.), Washington, DC 20052
| | - Constantine A Stratakis
- Section on Analytical and Functional Biophotonics (A.A., Y.A., F.A.C., V.C., A.A.A., A.G.), and Program on Developmental Endocrinology and Genetics (M.B.L., E.G, M.K., E.B., C.L., C.A.S.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Biostatistics and Clinical Epidemiology Service (N.S.), Clinical Research Center, National Institutes of Health, Bethesda, Maryland 20892; and George Washington University Department of System Engineering (T.A.M.), Washington, DC 20052
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Dąbrowska AK, Rotaru GM, Derler S, Spano F, Camenzind M, Annaheim S, Stämpfli R, Schmid M, Rossi RM. Materials used to simulate physical properties of human skin. Skin Res Technol 2015; 22:3-14. [DOI: 10.1111/srt.12235] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/15/2015] [Indexed: 01/18/2023]
Affiliation(s)
- A. K. Dąbrowska
- EMPA, Swiss Federal Laboratories for Materials Science and Technology; Laboratory for Protection and Physiology; St. Gallen Switzerland
| | - G.-M. Rotaru
- EMPA, Swiss Federal Laboratories for Materials Science and Technology; Laboratory for Protection and Physiology; St. Gallen Switzerland
| | - S. Derler
- EMPA, Swiss Federal Laboratories for Materials Science and Technology; Laboratory for Protection and Physiology; St. Gallen Switzerland
| | - F. Spano
- EMPA, Swiss Federal Laboratories for Materials Science and Technology; Laboratory for Protection and Physiology; St. Gallen Switzerland
| | - M. Camenzind
- EMPA, Swiss Federal Laboratories for Materials Science and Technology; Laboratory for Protection and Physiology; St. Gallen Switzerland
| | - S. Annaheim
- EMPA, Swiss Federal Laboratories for Materials Science and Technology; Laboratory for Protection and Physiology; St. Gallen Switzerland
| | - R. Stämpfli
- EMPA, Swiss Federal Laboratories for Materials Science and Technology; Laboratory for Protection and Physiology; St. Gallen Switzerland
| | - M. Schmid
- EMPA, Swiss Federal Laboratories for Materials Science and Technology; Laboratory for Protection and Physiology; St. Gallen Switzerland
| | - R. M. Rossi
- EMPA, Swiss Federal Laboratories for Materials Science and Technology; Laboratory for Protection and Physiology; St. Gallen Switzerland
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Campbell CL, Wood K, Valentine RM, Brown CTA, Moseley H. Monte Carlo modelling of daylight activated photodynamic therapy. Phys Med Biol 2015; 60:4059-73. [DOI: 10.1088/0031-9155/60/10/4059] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Hung CH, Chou TC, Hsu CK, Tseng SH. Broadband absorption and reduced scattering spectra of in-vivo skin can be noninvasively determined using δ-P1 approximation based spectral analysis. BIOMEDICAL OPTICS EXPRESS 2015; 6:443-56. [PMID: 25780735 PMCID: PMC4354575 DOI: 10.1364/boe.6.000443] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 12/04/2014] [Accepted: 01/02/2015] [Indexed: 05/16/2023]
Abstract
Previously, we revealed that a linear gradient line source illumination (LGLSI) geometry could work with advanced diffusion models to recover the sample optical properties at wavelengths where sample absorption and reduced scattering were comparable. In this study, we employed the LGLSI geometry with a broadband light source and utilized the spectral analysis to determine the broadband absorption and scattering spectra of turbid samples in the wavelength range from 650 to 1350 nm. The performance of the LGLSI δ-P1 diffusion model based spectral analysis was evaluated using liquid phantoms, and it was found that the sample optical properties could be properly recovered even at wavelengths above 1000 nm where μs' to μa ratios were in the range between 1 to 20. Finally, we will demonstrate the use of our system for recovering the 650 to 1350 nm absorption and scattering spectra of in-vivo human skin. We expect this system can be applied to study deep vessel dilation induced hemoglobin concentration variation and determine the water and lipid concentrations of in-vivo skin in clinical settings in the future.
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Affiliation(s)
- Cheng-Hung Hung
- Department of Photonics, National Cheng-Kung University, Tainan, 701,
Taiwan
| | - Ting-Chun Chou
- Department of Photonics, National Cheng-Kung University, Tainan, 701,
Taiwan
| | - Chao-Kai Hsu
- Department of Dermatology, National Cheng Kung University College of Medicine and Hospital, Tainan, 701,
Taiwan
| | - Sheng-Hao Tseng
- Department of Photonics, National Cheng-Kung University, Tainan, 701,
Taiwan
- Advanced Optoelectronic Technology Center, National Cheng-Kung University, Tainan, 701,
Taiwan
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Radosevich AJ, Eshein A, Nguyen TQ, Backman V. Subdiffusion reflectance spectroscopy to measure tissue ultrastructure and microvasculature: model and inverse algorithm. JOURNAL OF BIOMEDICAL OPTICS 2015; 20:097002. [PMID: 26414387 PMCID: PMC4963470 DOI: 10.1117/1.jbo.20.9.097002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 08/31/2015] [Indexed: 05/19/2023]
Abstract
Reflectance measurements acquired from within the subdiffusion regime (i.e., lengthscales smaller than a transport mean free path) retain much of the original information about the shape of the scattering phase function. Given this sensitivity, many models of subdiffusion regime light propagation have focused on parametrizing the optical signal through various optical and empirical parameters. We argue, however, that a more useful and universal way to characterize such measurements is to focus instead on the fundamental physical properties, which give rise to the optical signal. This work presents the methodologies that used to model and extract tissue ultrastructural and microvascular properties from spatially resolved subdiffusion reflectance spectroscopy measurements. We demonstrate this approach using ex-vivo rat tissue samples measured by enhanced backscattering spectroscopy.
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Affiliation(s)
- Andrew J. Radosevich
- Northwestern University, Biomedical Engineering, Tech E310, 2145 Sheridan Road, Evanston, Illinois 60208, United States
- Address all correspondence to: Andrew J. Radosevich, E-mail:
| | - Adam Eshein
- Northwestern University, Biomedical Engineering, Tech E310, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - The-Quyen Nguyen
- Northwestern University, Biomedical Engineering, Tech E310, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Vadim Backman
- Northwestern University, Biomedical Engineering, Tech E310, 2145 Sheridan Road, Evanston, Illinois 60208, United States
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Chen S, Lin X, Zhu C, Liu Q. Sequential weighted Wiener estimation for extraction of key tissue parameters in color imaging: a phantom study. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:127001. [PMID: 25467524 DOI: 10.1117/1.jbo.19.12.127001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 11/04/2014] [Indexed: 05/20/2023]
Abstract
Key tissue parameters, e.g., total hemoglobin concentration and tissue oxygenation, are important biomarkers in clinical diagnosis for various diseases. Although point measurement techniques based on diffuse reflectance spectroscopy can accurately recover these tissue parameters, they are not suitable for the examination of a large tissue region due to slow data acquisition. The previous imaging studies have shown that hemoglobin concentration and oxygenation can be estimated from color measurements with the assumption of known scattering properties, which is impractical in clinical applications. To overcome this limitation and speed-up image processing, we propose a method of sequential weighted Wiener estimation (WE) to quickly extract key tissue parameters, including total hemoglobin concentration (CtHb), hemoglobin oxygenation (StO2), scatterer density (α), and scattering power (β), from wide-band color measurements. This method takes advantage of the fact that each parameter is sensitive to the color measurements in a different way and attempts to maximize the contribution of those color measurements likely to generate correct results in WE. The method was evaluated on skin phantoms with varying CtHb, StO2, and scattering properties. The results demonstrate excellent agreement between the estimated tissue parameters and the corresponding reference values. Compared with traditional WE, the sequential weighted WE shows significant improvement in the estimation accuracy. This method could be used to monitor tissue parameters in an imaging setup in real time.
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42
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Lee MW, Hung CH, Liao JL, Cheng NY, Hou MF, Tseng SH. A linear gradient line source facilitates the use of diffusion models with high order approximation for efficient, accurate turbid sample optical properties recovery. BIOMEDICAL OPTICS EXPRESS 2014; 5:3628-39. [PMID: 25360378 PMCID: PMC4206330 DOI: 10.1364/boe.5.003628] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 08/31/2014] [Accepted: 09/12/2014] [Indexed: 05/19/2023]
Abstract
In this paper, we demonstrate that a scanning MEMS mirror can be employed to create a linear gradient line source that is equivalent to a planar source. This light source setup facilitates the use of diffusion models of increased orders of approximation having closed form solution, and thus enhance the efficiency and accuracy in sample optical properties recovery. In addition, compared with a regular planar light source, the linear gradient line source occupies much less source area and has an elevated measurement efficiency. We employed a δ-P1 diffusion equation with a closed form solution and carried out a phantom study to understand the performance of this new method in determining the absorption and scattering properties of turbid samples. Moreover, our Monte Carlo simulation results indicated that this geometry had probing depths comparable to those of the conventional diffuse reflectance measurement geometry with a source-detector separation of 3 mm. We expect that this new source setup would facilitate the investigating of superficial volumes of turbid samples in the wavelength regions where tissue absorption coefficients are comparable to scattering coefficients.
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Affiliation(s)
- Ming-Wei Lee
- Department of Photonics, National Cheng-Kung University, Tainan, Taiwan
| | - Cheng-Hung Hung
- Department of Photonics, National Cheng-Kung University, Tainan, Taiwan
| | - Jung-Li Liao
- Department of Photonics, National Cheng-Kung University, Tainan, Taiwan
| | - Nan-Yu Cheng
- Department of Photonics, National Cheng-Kung University, Tainan, Taiwan
| | - Ming-Feng Hou
- Department of Photonics, National Cheng-Kung University, Tainan, Taiwan
| | - Sheng-Hao Tseng
- Department of Photonics, National Cheng-Kung University, Tainan, Taiwan
- Advanced Optoelectronic Technology Center, National Cheng-Kung University, Tainan, Taiwan
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Zhong X, Wen X, Zhu D. Lookup-table-based inverse model for human skin reflectance spectroscopy: two-layered Monte Carlo simulations and experiments. OPTICS EXPRESS 2014; 22:1852-64. [PMID: 24515194 DOI: 10.1364/oe.22.001852] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Fiber reflectance spectroscopy is a non-invasive method for diagnosing skin diseases or evaluating aesthetic efficacy, but it is dependent on the inverse model validity. In this work, a lookup-table-based inverse model is developed using two-layered Monte Carlo simulations in order to extract the physiological and optical properties of skin. The melanin volume fraction and blood oxygen parameters are extracted from fiber reflectance spectra of in vivo human skin. The former indicates good coincidence with a commercial skin-melanin probe, and the latter (based on forearm venous occlusion and ischemia, and hot compress experiment) shows that the measurements are in agreement with physiological changes. These results verify the potential of this spectroscopy technique for evaluating the physiological characteristics of human skin.
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Sung KB, Shih KW, Hsu FW, Hsieh HP, Chuang MJ, Hsiao YH, Su YH, Tien GH. Accurate extraction of optical properties and top layer thickness of two-layered mucosal tissue phantoms from spatially resolved reflectance spectra. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:77002. [PMID: 25027003 DOI: 10.1117/1.jbo.19.7.077002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 06/17/2014] [Indexed: 05/11/2023]
Abstract
We are reporting on an experimental investigation of a movable diffuse reflectance spectroscopy system to extract diagnostically relevant optical properties of two-layered tissue phantoms simulating mucosae that are covered with stratified squamous epithelium. The reflectance spectra were measured at multiple sourcedetector separations using two imaging fiber bundles in contact with the phantoms, one with its optical axis perpendicular to the sample surface (perpendicular probe) and the other with its distal end beveled and optical axis tilted at 45 deg (oblique probe). Polystyrene microspheres and purified human hemoglobin were used to make tissue phantoms whose scattering and absorption properties could be well controlled and theoretically predicted. Monte Carlo simulations were used to predict the reflectance spectra for system calibration and an iterative curve fitting that simultaneously extracted the top layer reduced scattering coefficient, thickness, bottom layer reduced scattering coefficient, and hemoglobin concentration of the phantoms. The errors of the recovered parameters ranged from 7% to 20%. The oblique probe showed higher accuracy in the extracted top layer reduced scattering coefficient and thickness than the perpendicular probe. The developed system and data analysis methods provide a feasible tool to quantify the optical properties in vivo.
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Affiliation(s)
- Kung-Bin Sung
- National Taiwan University, Graduate Institute of Biomedical Electronics and Bioinformatics, No. 1 Sec. 4 Roosevelt Road, Taipei 10617, TaiwanbNational Taiwan University, Department of Electrical Engineering, No. 1 Sec. 4 Roosevelt Road, Taipei 10617, Tai
| | - Kuang-Wei Shih
- National Taiwan University, Graduate Institute of Biomedical Electronics and Bioinformatics, No. 1 Sec. 4 Roosevelt Road, Taipei 10617, Taiwan
| | - Fang-Wei Hsu
- National Taiwan University, Graduate Institute of Biomedical Electronics and Bioinformatics, No. 1 Sec. 4 Roosevelt Road, Taipei 10617, Taiwan
| | - Hong-Po Hsieh
- National Taiwan University, Graduate Institute of Biomedical Electronics and Bioinformatics, No. 1 Sec. 4 Roosevelt Road, Taipei 10617, Taiwan
| | - Min-Jie Chuang
- National Taiwan University, Graduate Institute of Biomedical Electronics and Bioinformatics, No. 1 Sec. 4 Roosevelt Road, Taipei 10617, Taiwan
| | - Yi-Hsien Hsiao
- National Taiwan University, Graduate Institute of Biomedical Electronics and Bioinformatics, No. 1 Sec. 4 Roosevelt Road, Taipei 10617, Taiwan
| | - Yu-Hui Su
- National Taiwan University, Graduate Institute of Biomedical Electronics and Bioinformatics, No. 1 Sec. 4 Roosevelt Road, Taipei 10617, Taiwan
| | - Gen-Hao Tien
- National Taiwan University, Graduate Institute of Biomedical Electronics and Bioinformatics, No. 1 Sec. 4 Roosevelt Road, Taipei 10617, Taiwan
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Sharma M, Hennessy R, Markey MK, Tunnell JW. Verification of a two-layer inverse Monte Carlo absorption model using multiple source-detector separation diffuse reflectance spectroscopy. BIOMEDICAL OPTICS EXPRESS 2013; 5:40-53. [PMID: 24466475 PMCID: PMC3891344 DOI: 10.1364/boe.5.000040] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 11/15/2013] [Accepted: 11/21/2013] [Indexed: 05/11/2023]
Abstract
A two-layer Monte Carlo lookup table-based inverse model is validated with two-layered phantoms across physiologically relevant optical property ranges. Reflectance data for source-detector separations of 370 μm and 740 μm were collected from these two-layered phantoms and top layer thickness, reduced scattering coefficient and the top and bottom layer absorption coefficients were extracted using the inverse model and compared to the known values. The results of the phantom verification show that this method is able to accurately extract top layer thickness and scattering when the top layer thickness ranges from 0 to 550 μm. In this range, top layer thicknesses were measured with an average error of 10% and the reduced scattering coefficient was measured with an average error of 15%. The accuracy of top and bottom layer absorption coefficient measurements was found to be highly dependent on top layer thickness, which agrees with physical expectation; however, within appropriate thickness ranges, the error for absorption properties varies from 12-25%.
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Affiliation(s)
- Manu Sharma
- Biomedical Engineering, The University of Texas at Austin 107 W. Dean Keeton, Austin, TX, 78712
USA
- These authors contributed equally to this paper
| | - Ricky Hennessy
- Biomedical Engineering, The University of Texas at Austin 107 W. Dean Keeton, Austin, TX, 78712
USA
- These authors contributed equally to this paper
| | - Mia K. Markey
- Biomedical Engineering, The University of Texas at Austin 107 W. Dean Keeton, Austin, TX, 78712
USA
- Imaging Physics, The University of Texas MD Anderson Cancer Center 1515 Holcombe Boulevard, Houston, TX, 77030
USA
| | - James W. Tunnell
- Biomedical Engineering, The University of Texas at Austin 107 W. Dean Keeton, Austin, TX, 78712
USA
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Calin MA, Parasca SV, Savastru R, Calin MR, Dontu S. Optical techniques for the noninvasive diagnosis of skin cancer. J Cancer Res Clin Oncol 2013; 139:1083-104. [PMID: 23552870 DOI: 10.1007/s00432-013-1423-3] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Accepted: 03/21/2013] [Indexed: 11/25/2022]
Abstract
PURPOSE The aim of this paper is to provide an overview of the most investigated optical diagnostic techniques: optical coherence tomography, fluorescence spectrometry, reflectance spectrometry, Raman spectroscopy, and confocal microscopy. METHODS A search of three databases was conducted using specific keywords and explicit inclusion and exclusion criteria for the analysis of the performances of these techniques in the pre- and postoperative diagnosis of skin cancers. RESULTS Optical coherence tomography has shown promising results in the assessment of deep margins of skin tumors and inflammatory skin diseases, but differentiating premalignant from malignant lesions proved to be less effective. Fluorescence spectroscopy proved to be effective in revealing the biochemical composition of tissue; early detection of malignant melanoma was reliable only with stepwise two-photon excitation of melanin, while tumoral margin assessment and differential diagnosis between malignant and non-malignant lesions showed some conflicting results. Characterization of the structural properties of tissue can be made using diffuse reflectance spectrometry, and the values of the specificity and sensitivity of this method are ranging between 72-92 % and 64-92 %, respectively. Raman spectroscopy proved to have better results both in carcinoma and melanoma diagnosis with sensitivities and specificities above 90 % and high above 50 %, respectively. Confocal microscopy is the closest technique to pathological examination and has gained the most clinical acceptance, despite the need for a standardization of the interpretation algorithm. CONCLUSIONS In conclusion, these optical techniques proved to be effective in the diagnosis of skin cancer, but further studies are needed in finding the appropriate method or combination of methods that can have wide clinical applications.
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Affiliation(s)
- Mihaela Antonina Calin
- National Institute of Research and Development for Optoelectronics INOE 2000, 409 Atomistilor Street, PO Box MG5, 077125 Magurele, Ilfov, Romania.
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Baranoski GVG, Dimson T, Chen TF, Kimmel B, Yim D, Miranda E. Rapid dissemination of light transport models on the web. IEEE COMPUTER GRAPHICS AND APPLICATIONS 2012; 32:10-15. [PMID: 24805997 DOI: 10.1109/mcg.2012.58] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Light transport models are employed in applications in such varied areas as realistic image synthesis, noninvasive treatment of diseases, and remote sensing of natural resources. Openly accessible research resources can lead to significant advances involving these applications by fostering the cross-fertilization of different scientific disciplines. However, few light transport models have their source code openly available for download. Moreover, simply making the code available might not be enough; these models' complexity usually prevents their use beyond the research groups that developed them. The NPSGD (Natural Phenomena Simulation Group Distributed) framework makes light transport models easily accessible for online use. NPSGD acts a front end, connecting model implementations to the Web. It lets researchers perform predictive and time-intensive light transport simulations in a user-friendly, fault-tolerant way. More important, as a proof of concept, NPSGD demonstrates that the reproducibility of research results through model transparency is feasible. Such reproducibility can result in fruitful collaborations between model developers and users, regardless of their field of expertise.
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48
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Tseng SH, Hou MF. Efficient determination of the epidermal optical properties using a diffusion model-based approach: Monte Carlo studies. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:087007. [PMID: 21895334 DOI: 10.1117/1.3609821] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In our previous studies, we have shown that the diffusing probe geometry can be used in conjunction with a two-layer diffusion model to accurately recover the absorption and scattering properties of skin in vivo. By modifying the original design to the diffusing probe with planar source (DPPS) geometry, we have also demonstrated that the efficiency of the accompanying multilayer diffusion model is comparable to that of a standard semi-infinite diffusion model; thus, precise quantification of superficial tissue optical properties in real time using a diffusion model becomes possible. In this study, the performance of the DPPS diffusion model is evaluated using Monte Carlo simulations and phantom measurements. It is found that the DPPS geometry is advantageous over the conventional planar source illumination geometry in interrogating superficial volumes of samples. In addition, our simulation results have shown that the DPPS geometry is capable of accurately recovering the optical properties of 50-μm thick epidermis and could be very useful in detecting cutaneous melanoma that has a radius as small as 250 μm.
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Affiliation(s)
- Sheng-Hao Tseng
- National Cheng-Kung University, Department of Photonics, Tainan 701, Taiwan.
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Yudovsky D, Nouvong A, Schomacker K, Pilon L. Monitoring temporal development and healing of diabetic foot ulceration using hyperspectral imaging. JOURNAL OF BIOPHOTONICS 2011; 4:565-76. [PMID: 21462349 DOI: 10.1002/jbio.201000117] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 01/25/2011] [Accepted: 03/03/2011] [Indexed: 05/22/2023]
Abstract
This study combines non-invasive hyperspectral imaging with an experimentally validated skin optical model and inverse algorithm to monitor diabetic feet of two representative patients. It aims to observe temporal changes in local epidermal thickness and oxyhemoglobin concentration and to gain insight into the progression of foot ulcer formation and healing. Foot ulceration is a debilitating comorbidity of diabetes that may result in loss of mobility and amputation. Inflammation and necrosis preempt ulceration and can result in changes in the skin prior to ulceration and during ulcer healing that affect oxygen delivery and consumption. Previous studies estimated oxyhemoglobin and deoxyhemoglobin concentrations around pre-ulcerative and ulcer sites on the diabetic foot using commercially available hyperspectral imaging systems. These measurements were successfully used to detect tissue at risk of ulceration and predict the healing potential of ulcers. The present study shows epidermal thickening and decrease in oxyhemoglobin concentration can also be detected prior to ulceration at pre-ulcerative sites. The algorithm was also able to observe reduction in the epidermal thickness combined with an increase in oxyhemoglobin concentration around the ulcer as it healed and closed. This methodology can be used for early prediction of diabetic foot ulceration in a clinical setting.
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Affiliation(s)
- Dmitry Yudovsky
- Henri Samueli School of Engineering and Applied Science, Biomedical Inter-Department Program, University of California-Los Angeles, Los Angeles, CA 90095-1597, USA
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50
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Yudovsky D, Pilon L. Retrieving skin properties from in vivo spectral reflectance measurements. JOURNAL OF BIOPHOTONICS 2011; 4:305-14. [PMID: 20680977 DOI: 10.1002/jbio.201000069] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
A previously developed inverse method was applied to in vivo normal-hemispherical spectral reflectance measurements taken on the inner and outer forearm as well as the forehead of healthy white Caucasian and black African subjects. The inverse method was used to determine the thickness and melanin concentration in the epidermis, dermal blood volume fraction and oxygen saturation, and skin's spectral scattering coefficient. It was established that changes in melanin concentration due to racial difference and tanning, and differences in epidermal thickness and blood volume with anatomical location were detectable. The retrieved values were also consistent with independent measurements reported in the literature. The same method could be used for optical diagnosis of pathologies affecting the structure and pigmentation of human skin.
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Affiliation(s)
- Dmitry Yudovsky
- University of California, Los Angeles, Henry Samueli School of Engineering and Applied Science, Mechanical and Aerospace Engineering Department, Biomedical Inter-Department Program, Los Angeles, CA 90095-1597, USA
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