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Mannoh EA, Baregamian N, Thomas G, Solόrzano CC, Mahadevan-Jansen A. Comparing laser speckle contrast imaging and indocyanine green angiography for assessment of parathyroid perfusion. Sci Rep 2023; 13:17270. [PMID: 37828222 PMCID: PMC10570279 DOI: 10.1038/s41598-023-42649-2] [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: 08/08/2023] [Accepted: 09/13/2023] [Indexed: 10/14/2023] Open
Abstract
Accurate intraoperative assessment of parathyroid blood flow is crucial to preserve function postoperatively. Indocyanine green (ICG) angiography has been successfully employed, however its conventional application has limitations. A label-free method overcomes these limitations, and laser speckle contrast imaging (LSCI) is one such method that can accurately detect and quantify differences in parathyroid perfusion. In this study, twenty-one patients undergoing thyroidectomy or parathyroidectomy were recruited to compare LSCI and ICG fluorescence intraoperatively. An experimental imaging device was used to image a total of 37 parathyroid glands. Scores of 0, 1 or 2 were assigned for ICG fluorescence by three observers based on perceived intensity: 0 for little to no fluorescence, 1 for moderate or patchy fluorescence, and 2 for strong fluorescence. Speckle contrast values were grouped according to these scores. Analyses of variance were performed to detect significant differences between groups. Lastly, ICG fluorescence intensity was calculated for each parathyroid gland and compared with speckle contrast in a linear regression. Results showed significant differences in speckle contrast between groups such that parathyroids with ICG score 0 had higher speckle contrast than those assigned ICG score 1, which in turn had higher speckle contrast than those assigned ICG score 2. This was further supported by a correlation coefficient of -0.81 between mean-normalized ICG fluorescence intensity and speckle contrast. This suggests that ICG angiography and LSCI detect similar differences in blood flow to parathyroid glands. Laser speckle contrast imaging shows promise as a label-free alternative that overcomes current limitations of ICG angiography for parathyroid assessment.
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Affiliation(s)
- Emmanuel A Mannoh
- Vanderbilt Biophotonics Center, Vanderbilt University, PMB 351631, Nashville, TN, 37235, USA.
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, 37235, USA.
| | - Naira Baregamian
- Division of Surgical Oncology and Endocrine Surgery, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
- Department of Surgery, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Giju Thomas
- Vanderbilt Biophotonics Center, Vanderbilt University, PMB 351631, Nashville, TN, 37235, USA
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, 37235, USA
| | - Carmen C Solόrzano
- Division of Surgical Oncology and Endocrine Surgery, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
- Department of Surgery, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Anita Mahadevan-Jansen
- Vanderbilt Biophotonics Center, Vanderbilt University, PMB 351631, Nashville, TN, 37235, USA.
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, 37235, USA.
- Department of Surgery, Vanderbilt University Medical Center, Nashville, TN, 37232, USA.
- Department of Neurological Surgery, Vanderbilt University Medical Center, Nashville, TN, 37232, USA.
- Department of Otolaryngology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA.
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Chizari A, Tsong W, Knop T, Steenbergen W. Prediction of motion artifacts caused by translation in handheld laser speckle contrast imaging. JOURNAL OF BIOMEDICAL OPTICS 2023; 28:046005. [PMID: 37082096 PMCID: PMC10112282 DOI: 10.1117/1.jbo.28.4.046005] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 03/24/2023] [Indexed: 05/03/2023]
Abstract
Significance In handheld laser speckle contrast imaging (LSCI), motion artifacts (MA) are inevitable. Suppression of MA leads to a valid and objective assessment of tissue perfusion in a wide range of medical applications including dermatology and burns. Our study shines light on the sources of these artifacts, which have not yet been explored. We propose a model based on optical Doppler effect to predict speckle contrast drop as an indication of MA. Aim We aim to theoretically model MA when an LSCI system measuring on static scattering media is subject to translational displacements. We validate the model using both simulation and experiments. This is the crucial first step toward creating robustness against MA. Approach Our model calculates optical Doppler shifts in order to predict intensity correlation function and contrast of the time-integrated intensity as functions of applied speed based on illumination and detection wavevectors. To validate the theoretical predictions, computer simulation of the dynamic speckles has been carried out. Then experiments are performed by both high-speed and low-framerate imaging. The employed samples for the experiments are a highly scattering matte surface and a Delrin plate of finite scattering level in which volume scattering occurs. Results An agreement has been found between theoretical prediction, simulation, and experimental results of both intensity correlation functions and speckle contrast. Coefficients in the proposed model have been linked to the physical parameters according to the experimental setups. Conclusions The proposed model provides a quantitative description of the influence of the types of illumination and media in the creation of MA. The accurate prediction of MA caused by translation based on Doppler shifts makes our model suitable to study the influence of rotation. Also the model can be extended for the case of dynamic media, such as live tissue.
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Affiliation(s)
- Ata Chizari
- University of Twente, Technical Medical Centre, Faculty of Science and Technology, Biomedical Photonic Imaging Group, Enschede, The Netherlands
- Address all correspondence to Ata Chizari,
| | - Wilson Tsong
- University of Twente, Technical Medical Centre, Faculty of Science and Technology, Biomedical Photonic Imaging Group, Enschede, The Netherlands
| | - Tom Knop
- University of Twente, Technical Medical Centre, Faculty of Science and Technology, Biomedical Photonic Imaging Group, Enschede, The Netherlands
| | - Wiendelt Steenbergen
- University of Twente, Technical Medical Centre, Faculty of Science and Technology, Biomedical Photonic Imaging Group, Enschede, The Netherlands
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Optical Coherence Tomography Angiography of the Intestine: How to Prevent Motion Artifacts in Open and Laparoscopic Surgery? Life (Basel) 2023; 13:life13030705. [PMID: 36983861 PMCID: PMC10055682 DOI: 10.3390/life13030705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 02/25/2023] [Accepted: 02/28/2023] [Indexed: 03/08/2023] Open
Abstract
(1) Introduction. The problem that limits the intraoperative use of OCTA for the intestinal circulation diagnostics is the low informative value of OCTA images containing too many motion artifacts. The aim of this study is to evaluate the efficiency and safety of the developed unit for the prevention of the appearance of motion artifacts in the OCTA images of the intestine in both open and laparoscopic surgery in the experiment; (2) Methods. A high-speed spectral-domain multimodal optical coherence tomograph (IAP RAS, Russia) operating at a wavelength of 1310 nm with a spectral width of 100 μm and a power of 2 mW was used. The developed unit was tested in two groups of experimental animals—on minipigs (group I, n = 10, open abdomen) and on rabbits (group II, n = 10, laparoscopy). Acute mesenteric ischemia was modeled and then 1 h later the small intestine underwent OCTA evaluation. A total of 400 OCTA images of the intact and ischemic small intestine were obtained and analyzed. The quality of the obtained OCTA images was evaluated based on the score proposed in 2020 by the group of Magnin M. (3) Results. Without stabilization, OCTA images of the intestine tissues were informative only in 32–44% of cases in open surgery and in 14–22% of cases in laparoscopic surgery. A vacuum bowel stabilizer with a pressure deficit of 22–25 mm Hg significantly reduced the number of motion artifacts. As a result, the proportion of informative OCTA images in open surgery increased up to 86.5% (Χ2 = 200.2, p = 0.001), and in laparoscopy up to 60% (Χ2 = 148.3, p = 0.001). (4) Conclusions. The used vacuum tissue stabilizer enabled a significant increase in the proportion of informative OCTA images by significantly reducing the motion artifacts.
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4
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Flowmotion imaging analysis of spatiotemporal variations in skin microcirculatory perfusion. Microvasc Res 2023; 146:104456. [PMID: 36403668 DOI: 10.1016/j.mvr.2022.104456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/02/2022] [Accepted: 11/12/2022] [Indexed: 11/19/2022]
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Heeman W, Maassen H, Dijkstra K, Calon J, van Goor H, Leuvenink H, van Dam GM, Boerma EC. Real-time, multi-spectral motion artefact correction and compensation for laser speckle contrast imaging. Sci Rep 2022; 12:21718. [PMID: 36522524 PMCID: PMC9755276 DOI: 10.1038/s41598-022-26154-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 12/09/2022] [Indexed: 12/23/2022] Open
Abstract
Laser speckle contrast imaging (LSCI) is so sensitive to motion that it can measure the movement of red blood cells. However, this extreme sensitivity to motion is also its pitfall as the clinical translation of LSCI is slowed down due to the inability to deal with motion artefacts. In this paper we study the effectiveness of a real-time, multi-spectral motion artefact correction and compensation by subduing an in vitro flow phantom and ex vivo porcine kidney to computer-controlled motion artefacts. On the in vitro flow phantom, the optical flow showed a good correlation with the total movement. This model results in a better signal-to-noise ratios for multiple imaging distances and the overestimation of perfusion was reduced. In the ex vivo kidney model, the perfusion overestimation was also reduced and we were still able to distinguish between ischemia and non-ischemia in the stabilized data whereas this was not possible in the non-stabilized data. This leads to a notably better perfusion estimation that could open the door to a multitude of new clinical applications for LSCI.
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Affiliation(s)
- Wido Heeman
- grid.4830.f0000 0004 0407 1981Faculty Campus Fryslân, University of Groningen, Wirdumerdijk 34, Leeuwarden, 8911 CE The Netherlands ,grid.4494.d0000 0000 9558 4598Department of Surgery, University Medical Centre Groningen, Hanzeplein 1, Groningen, 9713 GZ The Netherlands ,LIMIS Development BV, Henri Dunantweg 2, Leeuwarden, 8934 AD The Netherlands
| | - Hanno Maassen
- grid.4494.d0000 0000 9558 4598Department of Surgery, University Medical Centre Groningen, Hanzeplein 1, Groningen, 9713 GZ The Netherlands ,grid.4494.d0000 0000 9558 4598Department of Pathology and Medical Biology, University Medical Centre Groningen, Hanzeplein 1, Groningen, 9713 GZ The Netherlands
| | - Klaas Dijkstra
- grid.461051.7Centre of Expertise in Computer Vision and Data Science, NHL Stenden University of Applied Sciences, Rengerslaan 8-10, Leeuwarden, 8917 DD The Netherlands
| | - Joost Calon
- ZiuZ Visual Intelligence, Stationsweg 3, Gorredijk, 8401 DK The Netherlands
| | - Harry van Goor
- grid.4494.d0000 0000 9558 4598Department of Pathology and Medical Biology, University Medical Centre Groningen, Hanzeplein 1, Groningen, 9713 GZ The Netherlands
| | - Henri Leuvenink
- grid.4494.d0000 0000 9558 4598Department of Surgery, University Medical Centre Groningen, Hanzeplein 1, Groningen, 9713 GZ The Netherlands
| | - Gooitzen. M. van Dam
- grid.4494.d0000 0000 9558 4598Department of Surgery, University Medical Centre Groningen, Hanzeplein 1, Groningen, 9713 GZ The Netherlands
| | - E. Christiaan Boerma
- grid.4830.f0000 0004 0407 1981Faculty Campus Fryslân, University of Groningen, Wirdumerdijk 34, Leeuwarden, 8911 CE The Netherlands ,grid.414846.b0000 0004 0419 3743Department of Intensive Care, Medical Centre Leeuwarden, Henri Dunantweg 2, Leeuwarden, 8934 AD The Netherlands
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Lertsakdadet BS, Kennedy GT, Stone R, Kowalczewski C, Kowalczewski AC, Natesan S, Christy RJ, Durkin AJ, Choi B. Assessing multimodal optical imaging of perfusion in burn wounds. Burns 2022; 48:799-807. [PMID: 34696954 DOI: 10.1016/j.burns.2021.08.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 08/04/2021] [Accepted: 08/31/2021] [Indexed: 12/15/2022]
Abstract
A critical need exists for early, accurate diagnosis of burn wound severity to help identify the course of treatment and outcome of the wound. Laser speckle imaging (LSI) is a promising blood perfusion imaging approach, but it does not account for changes in tissue optical properties that can occur with burn wounds, which are highly dynamic environments. Here, we studied optical property dynamics following burn injury and debridement and the associated impact on interpretation of LSI measurements of skin perfusion. We used spatial frequency domain imaging (SFDI) measurements of tissue optical properties to study the impact of burn-induced changes in these properties on LSI measurements. An established preclinical porcine model of burn injury was used (n = 8). SFDI and LSI data were collected from burn wounds of varying severity. SFDI measurements demonstrate that optical properties change in response to burn injury in a porcine model. We then apply theoretical modeling to demonstrate that the measured range of optical property changes can affect the interpretation of LSI measurements of blood flow, but this effect is minimal for most of the measured data. Collectively, our results indicate that, even with a dynamic burn wound environment, blood-flow measurements with LSI can serve as an appropriate strategy for accurate assessment of burn severity.
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Affiliation(s)
- Ben S Lertsakdadet
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA 92612, USA; Department of Biomedical Engineering, University of California, Irvine, CA, 92697, USA.
| | - Gordon T Kennedy
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA 92612, USA.
| | - Randolph Stone
- United States Army Institute of Surgical Research, 36950 Chambers Pass, Fort Sam Houston, TX 78234, USA.
| | - Christine Kowalczewski
- United States Army Institute of Surgical Research, 36950 Chambers Pass, Fort Sam Houston, TX 78234, USA.
| | - Andrew C Kowalczewski
- United States Army Institute of Surgical Research, 36950 Chambers Pass, Fort Sam Houston, TX 78234, USA.
| | - Shanmugasundaram Natesan
- United States Army Institute of Surgical Research, 36950 Chambers Pass, Fort Sam Houston, TX 78234, USA.
| | - Robert J Christy
- United States Army Institute of Surgical Research, 36950 Chambers Pass, Fort Sam Houston, TX 78234, USA.
| | - Anthony J Durkin
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA 92612, USA; Department of Biomedical Engineering, University of California, Irvine, CA, 92697, USA.
| | - Bernard Choi
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA 92612, USA; Department of Biomedical Engineering, University of California, Irvine, CA, 92697, USA; Department of Surgery, University of California, Irvine, CA, 92697, USA; Edwards Lifesciences Center for Advanced Cardiovascular Technology, University of California, Irvine, CA, 92697, USA.
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7
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Oh E, Lee HC, Kim Y, Ning B, Lee SY, Cha J, Kim WW. A pilot feasibility study to assess vascularity and perfusion of parathyroid glands using a portable hand-held imager. Lasers Surg Med 2022; 54:399-406. [PMID: 34481419 PMCID: PMC8894507 DOI: 10.1002/lsm.23478] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 08/06/2021] [Accepted: 08/21/2021] [Indexed: 01/24/2023]
Abstract
OBJECTIVES Intraoperative localization and preservation of parathyroid glands (PGs) are challenging during thyroid surgery. A new noninvasive technique of combined near-infrared PG autofluorescence detection and dye-free imaging angiography that allows intraoperative feedback has recently been introduced. The objective of this study was to evaluate this technique in real-time. MATERIALS AND METHODS A pilot feasibility study of a portable imaging device in four patients who underwent either thyroid lobectomy or total thyroidectomy is presented. PG autofluorescence and vascularity/tissue perfusion were monitored using a real-time screen display during the surgical procedure. RESULTS Three lobectomies and one total thyroidectomy were performed. Among the nine PGs identified by the operating surgeon, eight PGs were confirmed using the autofluorescence device. Each PG was successfully determined to be either well-perfused or devascularized, and devascularized PGs were autotransplanted. CONCLUSIONS The preliminary results suggest that the combination of PG autofluorescence detection and dye-free angiography can potentially be used to assess PG function. With further validation studies, the effectiveness of this technique in clinical practice can be further delineated.
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Affiliation(s)
- Eugene Oh
- Department of Biomedical Engineering, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21212 USA,Sheikh Zayed Surgical Institute, Children’s National Hospital, 111 Michigan Ave., NW Washington, DC 20010, USA
| | - Hun Chan Lee
- Dept. of Mechanical Engineering, Boston University, 110 Cummington Mall Boston, MA 02215 USA
| | - Yoseph Kim
- Department of Biomedical Engineering, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21212 USA
| | - Bo Ning
- Sheikh Zayed Surgical Institute, Children’s National Hospital, 111 Michigan Ave., NW Washington, DC 20010, USA
| | - Seung Yup Lee
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 1760 Haygood Dr. NE, Atlanta, GA 30322 USA,Department of Electrical and Computer Engineering, Kennesaw State University, 840 Polytechnic Lane, Marietta, GA 30060, USA
| | - Jaepyeong Cha
- Sheikh Zayed Surgical Institute, Children’s National Hospital, 111 Michigan Ave., NW Washington, DC 20010, USA,George Washington University School of Medicine and Health Sciences, Department of Pediatrics, Washington DC, USA,Corresponding authors: Jaepyeong Cha, PhD, Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, 111 Michigan Ave. NW, Washington, DC 20010, Department of Pediatrics, George Washington University School of Medicine and Health Sciences, or , Tel: 202-476-6426; Wan Wook Kim, MD PhD, Department of Surgery, Kyungpook National University School of Medicine, 807 Hogukno, Buk-gu, Daegu 41404, South Korea, , Tel: 82-53-200-2705, Fax: 82-53-200-2027
| | - Wan Wook Kim
- Department of Surgery, Kyungpook National University Chilgok Hospital, 807 Hoguk-ro Buk-gu, Daegu, South Korea, 41404,Corresponding authors: Jaepyeong Cha, PhD, Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, 111 Michigan Ave. NW, Washington, DC 20010, Department of Pediatrics, George Washington University School of Medicine and Health Sciences, or , Tel: 202-476-6426; Wan Wook Kim, MD PhD, Department of Surgery, Kyungpook National University School of Medicine, 807 Hogukno, Buk-gu, Daegu 41404, South Korea, , Tel: 82-53-200-2705, Fax: 82-53-200-2027
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Guilbert J, Desjardins M. Movement correction method for laser speckle contrast imaging of cerebral blood flow in cranial windows in rodents. JOURNAL OF BIOPHOTONICS 2022; 15:e202100218. [PMID: 34658168 DOI: 10.1002/jbio.202100218] [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: 07/15/2021] [Revised: 09/07/2021] [Accepted: 10/08/2021] [Indexed: 06/13/2023]
Abstract
Laser speckle contrast imaging (LSCI) is used in clinical research to dynamically image blood flow. One drawback is its susceptibility to movement artifacts. We demonstrate a new, simple method to correct motion artifacts in LSCI signals measured in awake mice with cranial windows during sensory stimulation. The principle is to identify a region in the image in which speckle contrast (SC) is independent of blood flow and only varies with animal movement, then to regress out this signal from the data. We show that (1) the regressed signal correlates well with mouse head movement, (2) the corrected signal correlates better with independently measured blood volume and (3) it has a (59 ± 6)% higher signal-to-noise ratio. Compared to three alternative correction methods, ours has the best performance. Regressing out flow-independent global variations in SC is a simple and accessible way to improve the quality of LSCI measurements.
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Affiliation(s)
- Jérémie Guilbert
- Department of Physics, Physical Engineering and Optics, Université Laval, Québec City, Québec, Canada
- Oncology Division, Centre de recherche du CHU de Québec-Université Laval, Québec City, Québec, Canada
| | - Michèle Desjardins
- Department of Physics, Physical Engineering and Optics, Université Laval, Québec City, Québec, Canada
- Oncology Division, Centre de recherche du CHU de Québec-Université Laval, Québec City, Québec, Canada
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Chizari A, Schaap MJ, Knop T, Boink YE, Seyger MMB, Steenbergen W. Handheld versus mounted laser speckle contrast perfusion imaging demonstrated in psoriasis lesions. Sci Rep 2021; 11:16646. [PMID: 34404886 PMCID: PMC8371022 DOI: 10.1038/s41598-021-96218-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 08/06/2021] [Indexed: 02/08/2023] Open
Abstract
Enabling handheld perfusion imaging would drastically improve the feasibility of perfusion imaging in clinical practice. Therefore, we examine the performance of handheld laser speckle contrast imaging (LSCI) measurements compared to mounted measurements, demonstrated in psoriatic skin. A pipeline is introduced to process, analyze and compare data of 11 measurement pairs (mounted-handheld LSCI modes) operated on 5 patients and various skin locations. The on-surface speeds (i.e. speed of light beam movements on the surface) are quantified employing mean separation (MS) segmentation and enhanced correlation coefficient maximization (ECC). The average on-surface speeds are found to be 8.5 times greater in handheld mode compared to mounted mode. Frame alignment sharpens temporally averaged perfusion maps, especially in the handheld case. The results show that after proper post-processing, the handheld measurements are in agreement with the corresponding mounted measurements on a visual basis. The absolute movement-induced difference between mounted-handheld pairs after the background correction is [Formula: see text] (mean ± std, [Formula: see text]), with an absolute median difference of [Formula: see text]. Realization of handheld LSCI facilitates measurements on a wide range of skin areas bringing more convenience for both patients and medical staff.
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Affiliation(s)
- Ata Chizari
- Biomedical Photonic Imaging, Technical Medical Centre, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands.
| | - Mirjam J Schaap
- Department of Dermatology, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Tom Knop
- Biomedical Photonic Imaging, Technical Medical Centre, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands
| | - Yoeri E Boink
- Biomedical Photonic Imaging, Technical Medical Centre, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands.,Multi-Modality Medical Imaging, Technical Medical Centre, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands.,Department of Applied Mathematics, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands
| | - Marieke M B Seyger
- Department of Dermatology, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Wiendelt Steenbergen
- Biomedical Photonic Imaging, Technical Medical Centre, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands
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10
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Lee S, Namgoong JM, Kim Y, Cha J, Kim JK. Multimodal imaging of laser speckle contrast imaging combined with mosaic filter-based hyperspectral imaging for precise surgical guidance. IEEE Trans Biomed Eng 2021; 69:443-452. [PMID: 34260344 DOI: 10.1109/tbme.2021.3097122] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To enable a real-time surgical guidance system that simultaneously monitors blood vessel perfusion, oxygen saturation, thrombosis, and tissue recovery by combining multiple optical imaging techniques into a single system: visible imaging, mosaic filter-based snapshot hyperspectral imaging (HSI), and laser speckle contrast imaging (LSCI). METHODS The multimodal optical imaging system was demonstrated by clamping blood vessels in the small intestines of rats to create areas of restricted blood flow. Subsequent tissue damage and regeneration were monitored during procedures. Using LSCI, vessel perfusion was measured, revealing the biological activity and survival of organ tissues. Blood oxygen saturation was monitored using HSI in the near-infrared region. Principal component analysis was used over the spectral dimension to identify an HSI wavelength combination optimized for hemodynamic biomarker visualization. HSI and LSCI were complimentary, identifying thrombus generation and tissue recovery, which was not possible in either modality alone. RESULTS AND CONCLUSION By analyzing multimodal tissue information from visible imaging, LSCI perfusion imaging, and HSI, a recovery prognosis could be determined based on the blood supply to the organ. The unique combination of the complementary imaging techniques into a single surgical microscope holds promise for improving the real-time determination of blood supply and tissue prognosis during surgery. SIGNIFICANCE Precise real-time monitoring for vascular anomalies promises to reduce the risk of organ damage in precise surgical operations such as tissue resection and transplantation. In addition, the convergence of label-free imaging technologies removes delays associated with the injection and diffusion of vascular monitoring dyes.
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Heeman W, Maassen H, Calon J, van Goor H, Leuvenink H, van Dam GM, Boerma EC. Real-time visualization of renal microperfusion using laser speckle contrast imaging. JOURNAL OF BIOMEDICAL OPTICS 2021; 26:JBO-200389RR. [PMID: 34024055 PMCID: PMC8140613 DOI: 10.1117/1.jbo.26.5.056004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 05/07/2021] [Indexed: 05/02/2023]
Abstract
SIGNIFICANCE Intraoperative parameters of renal cortical microperfusion (RCM) have been associated with postoperative ischemia/reperfusion injury. Laser speckle contrast imaging (LSCI) could provide valuable information in this regard with the advantage over the current standard of care of being a non-contact and full-field imaging technique. AIM Our study aims to validate the use of LSCI for the visualization of RCM on ex vivo perfused human-sized porcine kidneys in various models of hemodynamic changes. APPROACH A comparison was made between three renal perfusion measures: LSCI, the total arterial renal blood flow (RBF), and sidestream dark-field (SDF) imaging in different settings of ischemia/reperfusion. RESULTS LSCI showed a good correlation with RBF for the reperfusion experiment (0.94 ± 0.02; p < 0.0001) and short- and long-lasting local ischemia (0.90 ± 0.03; p < 0.0001 and 0.81 ± 0.08; p < 0.0001, respectively). The correlation decreased for low flow situations due to RBF redistribution. The correlation between LSCI and SDF (0.81 ± 0.10; p < 0.0001) showed superiority over RBF (0.54 ± 0.22; p < 0.0001). CONCLUSIONS LSCI is capable of imaging RCM with high spatial and temporal resolutions. It can instantaneously detect local perfusion deficits, which is not possible with the current standard of care. Further development of LSCI in transplant surgery could help with clinical decision making.
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Affiliation(s)
- Wido Heeman
- University of Groningen, Faculty Campus Fryslân, Leeuwarden, The Netherlands
- University Medical Centre Groningen, Department of Surgery, Groningen, The Netherlands
- LIMIS Development BV, Leeuwarden, The Netherlands
- Address all correspondence to Wido Heeman,
| | - Hanno Maassen
- University Medical Centre Groningen, Department of Surgery, Groningen, The Netherlands
- University Medical Centre Groningen, Department of Pathology and Medical Biology, Groningen, The Netherlands
| | - Joost Calon
- ZiuZ Visual Intelligence, Gorredijk, The Netherlands
| | - Harry van Goor
- University Medical Centre Groningen, Department of Pathology and Medical Biology, Groningen, The Netherlands
| | - Henri Leuvenink
- University Medical Centre Groningen, Department of Surgery, Groningen, The Netherlands
| | - Gooitzen M. van Dam
- University Medical Centre Groningen, Department of Surgery, Groningen, The Netherlands
| | - E. Christiaan Boerma
- Medical Centre Leeuwarden, Department of Intensive Care, Leeuwarden, The Netherlands
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Transcranial chronic optical access to longitudinally measure cerebral blood flow. J Neurosci Methods 2020; 350:109044. [PMID: 33340556 DOI: 10.1016/j.jneumeth.2020.109044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 12/10/2020] [Accepted: 12/11/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND The regulation of cerebral blood flow is critical for normal brain functioning, and many physiological and pathological conditions can have long-term impacts on cerebral blood flow. However, minimally invasive tools to study chronic changes in animal models are limited. NEW METHOD We developed a minimally invasive surgical technique (cyanoacrylate skull, CAS) allowing us to image cerebral blood flow longitudinally through the intact mouse skull using laser speckle imaging. RESULTS With CAS we were able to detect acute changes in cerebral blood flow induced by hypercapnic challenge. We were also able to image cerebral blood flow dynamics with laser speckle imaging for over 100 days. Furthermore, the relative cerebral blood flow remained stable in mice from 30 days to greater than 100 days after the surgery. COMPARISON WITH EXISTING METHODS Previously, achieving continuous long-term optical access to measure cerebral blood flow in individual vessels in a mouse model involved invasive surgery. In contrast, the CAS technique presented here is relatively non-invasive, as it allows stable optical access through an intact mouse skull. CONCLUSIONS The CAS technique allows researcher to chronically measure cerebral blood flow dynamics for a significant portion of a mouse's lifespan. This approach may be useful for studying changes in blood flow due to cerebral pathology or for examining the therapeutic effects of modifying cerebral blood flow in mouse models relevant to human disease.
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13
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Ramondou P, Hersant J, Fouquet O, Sempore WY, Abraham P, Henni S. Current-Induced Vasodilation Specifically Detects, and Correlates With the Time Since, Last Aspirin Intake: An Interventional Study of 830 Patients. J Cardiovasc Pharmacol Ther 2020; 26:269-278. [PMID: 33161777 DOI: 10.1177/1074248420971165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Galvanic current-induced vasodilation (CIV) is impaired in patients under low-dose aspirin (ASA; ≤ 500 mg/day), but potential covariates and the impact of the time since the last ASA intake are unknown. OBJECTIVES We used tissue viability imaging (TiVi) in patients at risk of cardiovascular disease and examined its association with self-reported treatments. PATIENTS/METHODS We recorded the age, gender, height, weight, smoking status, and use of 14 different drug categories in 822 patients either with known peripheral artery disease or at risk thereof. The difference between TiVi arbitrary units (TAUs) where stimulation was applied and an adjacent skin area was recorded, as well as the time since the last ASA intake. Step-by-step regression analysis was used to determine the factors that affect CIV amplitude. RESULTS AND CONCLUSIONS CIV was 28.2 ± 22.9 vs. 14.6 ± 18.0 TAUs (P < 0.001) in patients treated with ASA (n = 287) and not treated with ASA (n = 535), respectively. The main determinants of CIV amplitude, by order of importance, were: aspirin intake, diabetes mellitus, age, and male sex. In ASA-treated patients, the main determinants were diabetes mellitus, time since the last ASA intake, male gender, and age. Non-invasive determination of the physiological effects of low-dose ASA is feasible in routine clinical practice. It could be a clinical approach to provide objective evidence of ASA intake, and potentially could be used to test adherence to treatment in ASA-treated patients.
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Affiliation(s)
- Pierre Ramondou
- Vascular Medicine, Angers University Hospital, Angers, France
| | - Jeanne Hersant
- Vascular Medicine, Angers University Hospital, Angers, France
| | | | - Wendsendate Yves Sempore
- 551563Sports and Exercise Medicine, Angers University Hospital, Angers, France.,UMR CNRS 1083 INSERM 6015, LUNAM University, Angers, France.,Université Nazi Boni, Bobo Dioulasso, Burkina Faso
| | - Pierre Abraham
- 551563Sports and Exercise Medicine, Angers University Hospital, Angers, France.,UMR CNRS 1083 INSERM 6015, LUNAM University, Angers, France
| | - Samir Henni
- Vascular Medicine, Angers University Hospital, Angers, France.,UMR CNRS 1083 INSERM 6015, LUNAM University, Angers, France
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14
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Chizari A, Knop T, Sirmacek B, van der Heijden F, Steenbergen W. Exploration of movement artefacts in handheld laser speckle contrast perfusion imaging. BIOMEDICAL OPTICS EXPRESS 2020; 11:2352-2365. [PMID: 32499928 PMCID: PMC7249814 DOI: 10.1364/boe.387252] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 03/20/2020] [Accepted: 03/30/2020] [Indexed: 05/19/2023]
Abstract
Functional performance of handheld laser speckle contrast imaging (LSCI) is compromised by movement artefacts. Here we quantify the movements of a handheld LSCI system employing electromagnetic (EM) tracking and measure the applied translational, tilt and on-surface laser beam speeds. By observing speckle contrast on static objects, the magnitudes of translation and tilt of wavefronts are explored for various scattering levels of the objects. We conclude that for tissue mimicking static phantoms, on-surface speeds play a dominant role to wavefront tilt speed in creation of movement artefacts. The ratio depends on the optical properties of the phantom. Furthermore, with the same applied speed, the drop in the speckle contrast increases with decreasing reduced scattering coefficient, and hence the related movement artefact increases.
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Affiliation(s)
- Ata Chizari
- University of Twente, Biomedical Photonic Imaging, Technical Medical Centre, Faculty of Science and Technology, Enschede, P.O. Box 217, 7500 AE, The Netherlands
| | - Tom Knop
- University of Twente, Biomedical Photonic Imaging, Technical Medical Centre, Faculty of Science and Technology, Enschede, P.O. Box 217, 7500 AE, The Netherlands
| | - Beril Sirmacek
- University of Twente, Robotics and Mechatronics, Technical Medical Centre, Faculty of Electrical Engineering, Mathematics and Computer Science, Enschede, P.O. Box 217, 7500 AE, The Netherlands
| | - Ferdinand van der Heijden
- University of Twente, Robotics and Mechatronics, Technical Medical Centre, Faculty of Electrical Engineering, Mathematics and Computer Science, Enschede, P.O. Box 217, 7500 AE, The Netherlands
| | - Wiendelt Steenbergen
- University of Twente, Biomedical Photonic Imaging, Technical Medical Centre, Faculty of Science and Technology, Enschede, P.O. Box 217, 7500 AE, The Netherlands
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15
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Lertsakdadet B, Dunn C, Bahani A, Crouzet C, Choi B. Handheld motion stabilized laser speckle imaging. BIOMEDICAL OPTICS EXPRESS 2019; 10:5149-5158. [PMID: 31646037 PMCID: PMC6788584 DOI: 10.1364/boe.10.005149] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 07/31/2019] [Accepted: 09/03/2019] [Indexed: 05/19/2023]
Abstract
Laser speckle imaging (LSI) is a wide-field, noninvasive optical technique that allows researchers and clinicians to quantify blood flow in a variety of applications. However, traditional LSI devices are cart or tripod based mounted systems that are bulky and potentially difficult to maneuver in a clinical setting. We previously showed that the use of a handheld LSI device with the use of a fiducial marker (FM) to account for motion artifact is a viable alternative to mounted systems. Here we incorporated a handheld gimbal stabilizer (HGS) to produce a motion stabilized LSI (msLSI) device to further improve the quality of data acquired in handheld configurations. We evaluated the msLSI device in vitro using flow phantom experiments and in vivo using a dorsal window chamber model. For in vitro experiments, we quantified the speckle contrast of the FM (KFM) using the mounted data set and tested 80% and 85% of KFM as thresholds for useable images (KFM,Mounted,80% and KFM,Mounted,85%). Handheld data sets using the msLSI device (stabilized handheld) and handheld data sets without the HGS (handheld) were collected. Using KFM,Mounted,80% and KFM,Mounted,85% as the threshold, the number of images above the threshold for stabilized handheld (38 ± 7 and 10 ± 2) was significantly greater (p = 0.031) than for handheld operation (16 ± 2 and 4 ± 1). We quantified a region of interest within the flow region (KFLOW), which led to a percent difference of 8.5% ± 2.9% and 7.8% ± 3.1% between stabilized handheld and handheld configurations at each threshold. For in vivo experiments, we quantified the speckle contrast of the window chamber (KWC) using the mounted data set and tested 80% of KWC (KWC,Mounted,80%). Stabilized handheld operation provided 53 ± 24 images above KWC,Mounted,80%, while handheld operation provided only 23 ± 13 images. We quantified the speckle flow index (SFI) of the vessels and the background to calculate a signal-to-background ratio (SBR) of the window chamber. Stabilized handheld operation provided a greater SBR (2.32 ± 0.29) compared to handheld operation (1.83 ± 0.21). Both the number of images above threshold and SBR were statistically significantly greater in the stabilized handheld data sets (p = 0.0312). These results display the improved usability of handheld data acquired with an msLSI device.
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Affiliation(s)
- Ben Lertsakdadet
- Beckman Laser Institute and Medical Clinic, University of California-Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
- Department of Biomedical Engineering, University of California, Irvine, 3120 Natural Sciences II, Irvine, CA 92697, USA
| | - Cody Dunn
- Beckman Laser Institute and Medical Clinic, University of California-Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
- Department of Biomedical Engineering, University of California, Irvine, 3120 Natural Sciences II, Irvine, CA 92697, USA
- Edwards Lifesciences Center for Advanced Cardiovascular Technology, University of California, Irvine, 2400 Engineering Hall, Irvine, CA 92697, USA
| | - Adrian Bahani
- Beckman Laser Institute and Medical Clinic, University of California-Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
- Department of Biomedical Engineering, University of California, Irvine, 3120 Natural Sciences II, Irvine, CA 92697, USA
| | - Christian Crouzet
- Beckman Laser Institute and Medical Clinic, University of California-Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
- Department of Biomedical Engineering, University of California, Irvine, 3120 Natural Sciences II, Irvine, CA 92697, USA
| | - Bernard Choi
- Beckman Laser Institute and Medical Clinic, University of California-Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
- Department of Biomedical Engineering, University of California, Irvine, 3120 Natural Sciences II, Irvine, CA 92697, USA
- Edwards Lifesciences Center for Advanced Cardiovascular Technology, University of California, Irvine, 2400 Engineering Hall, Irvine, CA 92697, USA
- Department of Surgery, University of California, Irvine, 333 City Boulevard West, Suite 1600, Orange, CA 92868, USA
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16
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Buijs J, Gucht JVD, Sprakel J. Fourier transforms for fast and quantitative Laser Speckle Imaging. Sci Rep 2019; 9:13279. [PMID: 31527699 PMCID: PMC6746788 DOI: 10.1038/s41598-019-49570-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 08/28/2019] [Indexed: 11/19/2022] Open
Abstract
Laser speckle imaging is a powerful imaging technique that visualizes microscopic motion within turbid materials. At current two methods are widely used to analyze speckle data: one is fast but qualitative, the other quantitative but computationally expensive. We have developed a new processing algorithm based on the fast Fourier transform, which converts raw speckle patterns into maps of microscopic motion and is both fast and quantitative, providing a dynamnic spectrum of the material over a frequency range spanning several decades. In this article we show how to apply this algorithm and how to measure a diffusion coefficient with it. We show that this method is quantitative and several orders of magnitude faster than the existing quantitative method. Finally we harness the potential of this new approach by constructing a portable laser speckle imaging setup that performs quantitative data processing in real-time on a tablet.
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Affiliation(s)
- J Buijs
- Physical Chemistry and Soft Matter, Wageningen University & Research, Stippeneng 4, 6708WE, Wageningen, The Netherlands
| | - J van der Gucht
- Physical Chemistry and Soft Matter, Wageningen University & Research, Stippeneng 4, 6708WE, Wageningen, The Netherlands
| | - J Sprakel
- Physical Chemistry and Soft Matter, Wageningen University & Research, Stippeneng 4, 6708WE, Wageningen, The Netherlands.
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17
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Heeman W, Steenbergen W, van Dam GM, Boerma EC. Clinical applications of laser speckle contrast imaging: a review. JOURNAL OF BIOMEDICAL OPTICS 2019; 24:1-11. [PMID: 31385481 PMCID: PMC6983474 DOI: 10.1117/1.jbo.24.8.080901] [Citation(s) in RCA: 130] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 07/02/2019] [Indexed: 05/02/2023]
Abstract
When a biological tissue is illuminated with coherent light, an interference pattern will be formed at the detector, the so-called speckle pattern. Laser speckle contrast imaging (LSCI) is a technique based on the dynamic change in this backscattered light as a result of interaction with red blood cells. It can be used to visualize perfusion in various tissues and, even though this technique has been extensively described in the literature, the actual clinical implementation lags behind. We provide an overview of LSCI as a tool to image tissue perfusion. We present a brief introduction to the theory, review clinical studies from various medical fields, and discuss current limitations impeding clinical acceptance.
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Affiliation(s)
- Wido Heeman
- University of Groningen, Faculty Campus Fryslân, Leeuwarden, The Netherlands
- University Medical Centre Groningen, Department of Surgery, Optical Molecular Imaging Groningen, Groningen, The Netherlands
- LIMIS Development BV, Leeuwarden, The Netherlands
| | - Wiendelt Steenbergen
- University of Twente, Techmed Center, Faculty of Science and Technology, Biomedical Photonic Imaging Group, Enschede, The Netherlands
| | - Gooitzen M. van Dam
- University Medical Centre Groningen, Department of Surgery, Optical Molecular Imaging Groningen, Groningen, The Netherlands
| | - E. Christiaan Boerma
- Medical Centre Leeuwarden, Department of Intensive Care, Leeuwarden, The Netherlands
- Address all correspondence to E. Christiaan Boerma, E-mail:
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18
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Chen H, Miao P, Bo B, Li Y, Tong S. A prototype system of portable laser speckle imager based on embedded graphics processing unit platform. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2019; 2019:3919-3922. [PMID: 31946729 DOI: 10.1109/embc.2019.8857273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Laser speckle contrast imaging (LSCI) is a high-resolution full-field optical technique for measuring blood flow, which has been widely used in clinical and biomedical research. However, most of the current LSCI instruments are bulky, limiting their application settings. In this work, we proposed a prototype system of portable laser speckle imager. Different from the desktop laser speckle systems that utilize personal computer (PC), our system was designed with embedded GPU system (Jetson TX2, NVIDIA, USA) and a LCD touch screen (16.5 × 12.4 cm in size, 380 g in weight). In-vivo experiments showed that the portable GPU-based system had comparable performance with our laboratory LSCI system. Such a portable LSCI imager could be potentially used in a situation that requires for easy operation and installation, such as intraoperative monitoring or bedside diagnosis.
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19
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Dunn CE, Lertsakdadet B, Crouzet C, Bahani A, Choi B. Comparison of speckleplethysmographic (SPG) and photoplethysmographic (PPG) imaging by Monte Carlo simulations and in vivo measurements. BIOMEDICAL OPTICS EXPRESS 2018; 9:4306-4316. [PMID: 30615714 PMCID: PMC6157764 DOI: 10.1364/boe.9.004306] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 07/11/2018] [Accepted: 07/20/2018] [Indexed: 05/02/2023]
Abstract
Noncontact photoplethysmography (PPG) is limited by a poor signal-to-noise ratio (SNR). A solution to this limitation is the use of alternate sources of optical contrast to generate a complementary pulsatile waveform. One such source is laser speckle contrast, which is modulated in biological tissues by the flow rate of red blood cells. Averaging a region of interest from a speckle contrast image over time allows for the calculation of a speckleplethysmogram (SPG). Similar to PPG, SPG enables monitoring of heart rate and respiratory rate. A gap in the knowledge base exists as to the precise spatiotemporal relationship between PPG and SPG signals. We have developed an eight-layer tissue model to simulate both PPG and SPG signals in a reflectance geometry via Monte Carlo methods. We modeled PPG by compression of the upper and lower blood nets due to expansion of the larger arterial layer below. The in silico PPG peak-to-peak amplitude percent was greater at 532 nm than at 860 nm (5.6% vs. 3.0%, respectively), which matches trends from the literature. We modeled SPG by changing flow speeds of red blood cells in both the capillaries and arterioles over the cardiac cycle. The in silico SPG peak-to-peak amplitude percent was 24% at 532 nm and 40% at 860 nm. In silico results are similar to in vivo results measured with a two-camera set up for simultaneous imaging of PPG and SPG. Both in silico and in vivo data suggest SPG has a much larger SNR than PPG, which may prove beneficial for noncontact, wide-field optical monitoring of cardiovascular health.
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Affiliation(s)
- Cody E. Dunn
- Beckman Laser Institute and Medical Clinic, University of California-Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
- Department of Biomedical Engineering, University of California, Irvine, 3120 Natural Sciences II, Irvine, CA 92697, USA
- Edwards Lifesciences Center for Advanced Cardiovascular Technology, University of California, Irvine, 2400 Engineering Hall, Irvine, CA 92697, USA
| | - Ben Lertsakdadet
- Beckman Laser Institute and Medical Clinic, University of California-Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
- Department of Biomedical Engineering, University of California, Irvine, 3120 Natural Sciences II, Irvine, CA 92697, USA
| | - Christian Crouzet
- Beckman Laser Institute and Medical Clinic, University of California-Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
- Department of Biomedical Engineering, University of California, Irvine, 3120 Natural Sciences II, Irvine, CA 92697, USA
| | - Adrian Bahani
- Beckman Laser Institute and Medical Clinic, University of California-Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
- Department of Biomedical Engineering, University of California, Irvine, 3120 Natural Sciences II, Irvine, CA 92697, USA
| | - Bernard Choi
- Beckman Laser Institute and Medical Clinic, University of California-Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
- Department of Biomedical Engineering, University of California, Irvine, 3120 Natural Sciences II, Irvine, CA 92697, USA
- Edwards Lifesciences Center for Advanced Cardiovascular Technology, University of California, Irvine, 2400 Engineering Hall, Irvine, CA 92697, USA
- Department of Surgery, University of California, Irvine, 333 City Boulevard West, Suite 1600, Orange, CA 92868, USA
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20
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Ghijsen M, Rice TB, Yang B, White SM, Tromberg BJ. Wearable speckle plethysmography (SPG) for characterizing microvascular flow and resistance. BIOMEDICAL OPTICS EXPRESS 2018; 9:3937-3952. [PMID: 30338166 PMCID: PMC6191642 DOI: 10.1364/boe.9.003937] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 07/11/2018] [Accepted: 07/18/2018] [Indexed: 05/04/2023]
Abstract
In this work we introduce a modified form of laser speckle imaging (LSI) referred to as affixed transmission speckle analysis (ATSA) that uses a single coherent light source to probe two physiological signals: one related to pulsatile vascular expansion (classically known as the photoplethysmographic (PPG) waveform) and one related to pulsatile vascular blood flow (named here the speckle plethysmographic (SPG) waveform). The PPG signal is determined by recording intensity fluctuations, and the SPG signal is determined via the LSI dynamic light scattering technique. These two co-registered signals are obtained by transilluminating a single digit (e.g. finger) which produces quasi-periodic waveforms derived from the cardiac cycle. Because PPG and SPG waveforms probe vascular expansion and flow, respectively, in cm-thick tissue, these complementary phenomena are offset in time and have rich dynamic features. We characterize the timing offset and harmonic content of the waveforms in 16 human subjects and demonstrate physiologic relevance for assessing microvascular flow and resistance.
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Affiliation(s)
- Michael Ghijsen
- Laser Microbeam and Medical Program, Beckman Laser Institute, 1002 Health Sciences Road, Irvine, CA 92612, USA
- Department of Biomedical Engineering, University of California, Irvine, CA 92697, USA
| | - Tyler B. Rice
- Laser Associated Sciences Inc., 16 Foxglove Way, Irvine, CA 92612, USA
| | - Bruce Yang
- Laser Associated Sciences Inc., 16 Foxglove Way, Irvine, CA 92612, USA
| | - Sean M. White
- Laser Associated Sciences Inc., 16 Foxglove Way, Irvine, CA 92612, USA
| | - Bruce J. Tromberg
- Laser Microbeam and Medical Program, Beckman Laser Institute, 1002 Health Sciences Road, Irvine, CA 92612, USA
- Department of Biomedical Engineering, University of California, Irvine, CA 92697, USA
- Department of Surgery, University of California, Irvine Medical Center, Orange, CA 92868, USA
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