Prof. Guoqiang Yu Profile

Prof. Guoqiang Yu

Professor at Univ of Kentucky

SPIE Involvement:

Author

Publications (40)

Proceedings Article | 13 March 2024 Presentation

An affordable miniaturized speckle contrast diffuse correlation tomography (scDCT) device for 2D mapping of cerebral blood flow

Fatemeh Hamedi, Chong Huang, Faezeh Akbari, Xuhui Liu, Mehrana Mohtasebi, Chaebeom Yeo, Lei Chen, Guoqiang Yu

Proceedings Volume PC12827, PC128270E (2024) https://doi.org/10.1117/12.3001780

KEYWORDS: Miniaturization, Tomography, Speckle, Cerebral blood flow, Portability, Brain, Neuroimaging, Equipment, Cameras, Brain mapping

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Proceedings Article | 13 March 2024 Presentation

Laser coherence length requirement for speckle contrast diffuse correlation tomography (scDCT)

Faezeh Akbari, Fatemeh Hamedi, Mehrana Mohtasebi, Faraneh Fathi, Chong Huang, Lei Chen, Guoqiang Yu

Proceedings Volume PC12827, PC128270P (2024) https://doi.org/10.1117/12.3001788

KEYWORDS: Physical coherence, Laser stabilization, Tomography, Speckle, Laser crystals, Signal to noise ratio, Optical coherence, Laser speckle contrast imaging, Image restoration, Crystals

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SPIE Journal Paper | 14 November 2023 Open Access

Depth-sensitive diffuse speckle contrast topography for high-density mapping of cerebral blood flow in rodents

Mehrana Mohtasebi, Dara Singh, Xuhui Liu, Faraneh Fathi, Samaneh Rabienia Haratbar, Kathryn E. Saatman, Lei Chen, Guoqiang Yu

NPh, Vol. 10, Issue 04, 045007, (November 2023) https://doi.org/10.1117/12.10.1117/1.NPh.10.4.045007

KEYWORDS: Speckle, Laser speckle contrast imaging, Windows, Brain mapping, Simulation of CCA and DLA aggregates, Brain, 3D modeling, Spatial resolution, Tissues, Neurophotonics

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SignificanceFrequent assessment of cerebral blood flow (CBF) is crucial for the diagnosis and management of cerebral vascular diseases. In contrast to large and expensive imaging modalities, such as nuclear medicine and magnetic resonance imaging, optical imaging techniques are portable and inexpensive tools for continuous measurements of cerebral hemodynamics. The recent development of an innovative noncontact speckle contrast diffuse correlation tomography (scDCT) enables three-dimensional (3D) imaging of CBF distributions. However, scDCT requires complex and time-consuming 3D reconstruction, which limits its ability to achieve high spatial resolution without sacrificing temporal resolution and computational efficiency.AimWe investigate a new diffuse speckle contrast topography (DSCT) method with parallel computation for analyzing scDCT data to achieve fast and high-density two-dimensional (2D) mapping of CBF distributions at different depths without the need for 3D reconstruction.ApproachA new moving window method was adapted to improve the sampling rate of DSCT. A fast computation method utilizing MATLAB functions in the Image Processing Toolbox™ and Parallel Computing Toolbox™ was developed to rapidly generate high-density CBF maps. The new DSCT method was tested for spatial resolution and depth sensitivity in head-simulating layered phantoms and in-vivo rodent models.ResultsDSCT enables 2D mapping of the particle flow in the phantom at different depths through the top layer with varied thicknesses. Both DSCT and scDCT enable the detection of global and regional CBF changes in deep brains of adult rats. However, DSCT achieves fast and high-density 2D mapping of CBF distributions at different depths without the need for complex and time-consuming 3D reconstruction.ConclusionsThe depth-sensitive DSCT method has the potential to be used as a noninvasive, noncontact, fast, high resolution, portable, and inexpensive brain imager for basic neuroscience research in small animal models and for translational studies in human neonates.

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SPIE Journal Paper | 4 May 2023 Open Access

Detection of low-frequency oscillations in neonatal piglets with speckle contrast diffuse correlation tomography

Mehrana Mohtasebi, Daniel Irwin, Dara Singh, Siavash Mazdeyasna, Xuhui Liu, Samaneh Rabienia Haratbar, Faraneh Fathi, Chong Huang, Kathryn Saatman, Lei Chen, Guoqiang Yu

JBO, Vol. 28, Issue 12, 121204, (May 2023) https://doi.org/10.1117/12.10.1117/1.JBO.28.12.121204

KEYWORDS: Brain, Ischemia, Simulation of CCA and DLA aggregates, Windows, Speckle, 3D image reconstruction, Sampling rates, Tissues, Reconstruction algorithms, Neuroimaging

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Proceedings Article | 7 March 2022 Presentation

Noncontact optical assessment of disrupted cerebral functional connectivity in a piglet model of transient ischemic stroke

Mehrana Mohtasebi, Lei Chen, Siavash Mazdeyasna, Dara Singh, Xuhui Liu, Chong Huang, Samaneh Rabienia Haratbar, Faraneh Fathi, David Powell, Kathryn Saatman, Qiang Cheng, Guoqiang Yu

Proceedings Volume PC11945, PC1194505 (2022) https://doi.org/10.1117/12.2609144

KEYWORDS: Ischemic stroke, Brain, Tissue optics, Stereoscopy, Traumatic brain injury, Tomography, Tissues, Speckle, Signal attenuation, Safety

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Proceedings Article | 7 March 2022 Presentation

Laser speckle contrast imaging of cerebral blood flow using picosecond pulsed laser illumination

Faraneh Fathi, Siavash Mazdeyasna, Mehrana Mohtasebi, Dara Singh, Xuhui Liu, Chong Huang, Samaneh Rabienia Haratbar, Lei Chen, Guoqiang Yu

Proceedings Volume PC11944, PC119440G (2022) https://doi.org/10.1117/12.2610178

KEYWORDS: Laser speckle contrast imaging, Pulsed laser operation, Picosecond phenomena, Imaging systems, Cerebral blood flow, Continuous wave operation, Diffusers, System integration, Laser crystals, Glasses

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Proceedings Article | 7 March 2022 Presentation

Wearable optical sensor for continuous monitoring of cerebral ischemia in rodents and piglets

Xuhui Liu, Lei Chen, Chong Huang, Mehrana Mohtasebi, Siavash Mazdeyasna, David Powell, Faraneh Fathi, Samaneh Rabienia Haratbar, Daniel Iwrin, Yutong Gu, Guoqiang Yu

Proceedings Volume PC11956, PC1195601 (2022) https://doi.org/10.1117/12.2608257

KEYWORDS: Ischemia, Optical sensors, Simulation of CCA and DLA aggregates, Semiconductor lasers, Detector arrays, Spectroscopy, Speckle, Neuroscience, Laser tissue interaction, Head

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Proceedings Article | 2 March 2022 Poster

A fast algorithm towards real-time laser speckle contrast imaging

Dara Singh, Lei Chen, Chong Huang, Siavash Mazdeyasna, Faraneh Fathi, Mehrana Mohtasebi, Guoqiang Yu

Proceedings Volume PC11971, PC119710R (2022) https://doi.org/10.1117/12.2609939

KEYWORDS: Laser speckle contrast imaging, Speckle pattern, Parallel computing, MATLAB, Laser applications, Algorithm development, Skull, Natural surfaces, Laser tissue interaction, Image quality

Proceedings Article | 5 March 2021 Presentation

A wearable fiber-free optical sensor for continuous monitoring of cerebral blood flow in freely moving mice

Xuhui Liu, Chong Huang, Yutong Gu, Elie Abu Jawdeh, Henrietta Bada, Kevin Donohue, Lei Chen, Guoqiang Yu

Proceedings Volume 11638, 116380A (2021) https://doi.org/10.1117/12.2577309

KEYWORDS: Cerebral blood flow, Optical sensors, Fiber optics sensors, Tissues, Semiconductor lasers, Detector arrays, Carbon dioxide, Brain, Speckle, Skull

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Proceedings Article | 5 March 2021 Presentation + Paper

Noncontact optical assessment of spontaneous low-frequency fluctuations of cerebral blood flow in neonatal intraventricular hemorrhage

Mehrana Mohtasebi, Chong Huang, Siavash Mazdeyasna, Brennen Green, Kathryn Saatman, Qiang Cheng, Lei Chen, Guoqiang Yu

Proceedings Volume 11629, 116290U (2021) https://doi.org/10.1117/12.2578019

KEYWORDS: Brain, Cerebral blood flow, Signal attenuation, Tomography, Stereoscopy, Speckle, Neuroimaging, Hemodynamics, Blood vessels, 3D modeling

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SPIE Journal Paper | 29 January 2021 Open Access

Simultaneous measurements of tissue blood flow and oxygenation using a wearable fiber-free optical sensor

Xuhui Liu, Yutong Gu, Chong Huang, Mingjun Zhao, Yanda Cheng, Elie Abu Jawdeh, Henrietta Bada, Lei Chen, Guoqiang Yu

JBO, Vol. 26, Issue 01, 012705, (January 2021) https://doi.org/10.1117/12.10.1117/1.JBO.26.1.012705

KEYWORDS: Blood circulation, Tissues, Semiconductor lasers, Cameras, Arteries, Tissue optics, Speckle, Signal to noise ratio, Skin, Near infrared spectroscopy

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SPIE Journal Paper | 24 September 2018 Open Access

Noncontact speckle contrast diffuse correlation tomography of blood flow distributions in tissues with arbitrary geometries

Siavash Mazdeyasna, Chong Huang, Mingjun Zhao, Nneamaka B. Agochukwu, Ahmed A. Bahrani, Lesley Wong, Guoqiang Yu

JBO, Vol. 23, Issue 09, 096005, (September 2018) https://doi.org/10.1117/12.10.1117/1.JBO.23.9.096005

KEYWORDS: Tissues, Blood circulation, Natural surfaces, Image restoration, Skin, Speckle, Imaging systems, Sensors, Tomography, Cameras

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SPIE Journal Paper | 26 August 2016 Open Access

Diffuse optical measurements of head and neck tumor hemodynamics for early prediction of chemoradiation therapy outcomes

Lixin Dong, Mahesh Kudrimoti, Daniel Irwin, Li Chen, Sameera Kumar, Yu Shang, Chong Huang, Ellis Johnson, Scott Stevens, Brent Shelton, Guoqiang Yu

JBO, Vol. 21, Issue 08, 085004, (August 2016) https://doi.org/10.1117/12.10.1117/1.JBO.21.8.085004

KEYWORDS: Tumors, Hemodynamics, Chromium, Optical testing, Neck, Head, Tissues, Radiotherapy, Cancer, Tissue optics

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SPIE Journal Paper | 8 August 2016 Open Access

Low-cost compact diffuse speckle contrast flowmeter using small laser diode and bare charge-coupled-device

Chong Huang, Myeongsu Seong, Joshua Paul Morgan, Siavash Mazdeyasna, Jae Gwan Kim, Jeffrey Todd Hastings, Guoqiang Yu

JBO, Vol. 21, Issue 08, 080501, (August 2016) https://doi.org/10.1117/12.10.1117/1.JBO.21.8.080501

KEYWORDS: Tissues, Charge-coupled devices, Semiconductor lasers, Speckle, CCD cameras, Sensors, Blood circulation, CCD image sensors, Natural surfaces, Lenses

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Proceedings Article | 27 April 2016 Presentation

Noncontact diffuse optical assessment of blood flow changes in head and neck free tissue transfer flaps (Conference Presentation)

Chong Huang, Jeffrey Radabaugh, Rony Aouad, Yu Lin, Thomas Gal, Amit Patel, Joseph Valentino, Yu Shang, Guoqiang Yu

Proceedings Volume 9689, 96891V (2016) https://doi.org/10.1117/12.2207934

KEYWORDS: Tissue optics, Head, Neck, Tissues, Blood circulation, Cancer, Surgery, Failure analysis, Spectroscopy, Diagnostics

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Proceedings Article | 27 April 2016 Presentation

Diffuse optical measurements of head and neck tumor hemodynamics for early prediction of radiation therapy (Conference Presentation)

Lixin Dong, Mahesh Kudrimoti, Daniel Irwin, Li Chen, Yu Shang, Xingzhe Li, Scott Stevens, Brent Shelton, Guoqiang Yu

Proceedings Volume 9698, 969809 (2016) https://doi.org/10.1117/12.2207981

KEYWORDS: Tumors, Hemodynamics, Radiotherapy, Head, Neck, Optical testing, Blood circulation, Cancer, Lithium, Optical components

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SPIE Journal Paper | 23 December 2015 Open Access

Hybrid diffuse optical techniques for continuous hemodynamic measurement in gastrocnemius during plantar flexion exercise

Brad Henry, Mingjun Zhao, Yu Shang, Timothy Uhl, D. Travis Thomas, Eleftherios Xenos, Sibu Saha, Guoqiang Yu

JBO, Vol. 20, Issue 12, 125006, (December 2015) https://doi.org/10.1117/12.10.1117/1.JBO.20.12.125006

KEYWORDS: Hemodynamics, Calibration, Adaptive optics, Tissues, Near infrared, Oxygen, Hybrid optics, Optical testing, Tissue optics, Biomedical optics

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SPIE Journal Paper | 11 August 2015 Open Access

Noncontact diffuse correlation tomography of human breast tumor

Lian He, Yu Lin, Chong Huang, Daniel Irwin, Margaret Szabunio, Guoqiang Yu

JBO, Vol. 20, Issue 08, 086003, (August 2015) https://doi.org/10.1117/12.10.1117/1.JBO.20.8.086003

KEYWORDS: Tumors, Breast, Tissues, Blood circulation, Image restoration, Tomography, Ultrasonography, Natural surfaces, Imaging systems, 3D image processing

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SPIE Journal Paper | 17 July 2015 Open Access

Noncontact diffuse optical assessment of blood flow changes in head and neck free tissue transfer flaps

Chong Huang, Jeffrey Radabaugh, Rony Aouad, Yu Lin, Thomas Gal, Amit Patel, Joseph Valentino, Yu Shang, Guoqiang Yu

JBO, Vol. 20, Issue 07, 075008, (July 2015) https://doi.org/10.1117/12.10.1117/1.JBO.20.7.075008

KEYWORDS: Blood circulation, Tissues, Tissue optics, Head, Neck, Surgery, Biomedical optics, Near infrared, Natural surfaces, Doppler effect

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SPIE Journal Paper | 8 January 2014 Open Access

Near-infrared diffuse optical monitoring of cerebral blood flow and oxygenation for the prediction of vasovagal syncope

Ran Cheng, Yu Shang, Siqi Wang, Joyce Evans, Abner Rayapati, David Randall, Guoqiang Yu

JBO, Vol. 19, Issue 01, 017001, (January 2014) https://doi.org/10.1117/12.10.1117/1.JBO.19.1.017001

KEYWORDS: Hemodynamics, Cerebral blood flow, Near infrared spectroscopy, Blood pressure, Tissues, Biomedical optics, Blood circulation, Brain, Tissue optics, Blood

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SPIE Journal Paper | 4 October 2013 Open Access

Noninvasive evaluation of electrical stimulation impacts on muscle hemodynamics via integrating diffuse optical spectroscopies with muscle stimulator

Yu Shang, Yu Lin, Brad Henry, Ran Cheng, Chong Huang, Li Chen, Brent Shelton, Karin Swartz, Sara Salles, Guoqiang Yu

JBO, Vol. 18, Issue 10, 105002, (October 2013) https://doi.org/10.1117/12.10.1117/1.JBO.18.10.105002

KEYWORDS: Tissues, Hemodynamics, Blood circulation, Tissue optics, Near infrared spectroscopy, Optical fibers, Oxygen, Heart, Skin, Blood

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SPIE Journal Paper | 24 May 2013 Open Access

Diffuse optical characterization of an exercising patient group with peripheral artery disease

Rickson Mesquita, Mary Putt, Malavika Chandra, Guoqiang Yu, Xiaoman Xing, Sung Wan Han, Gwen Lech, Yu Shang, Turgut Durduran, Chao Zhou, Arjun Yodh, Emile Mohler

JBO, Vol. 18, Issue 05, 057007, (May 2013) https://doi.org/10.1117/12.10.1117/1.JBO.18.5.057007

KEYWORDS: Control systems, Arteries, Blood circulation, Tissue optics, Biomedical optics, Near infrared spectroscopy, Optical testing, Statistical analysis, Tissues, Data modeling

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SPIE Journal Paper | 1 March 2013 Open Access

Using optical fibers with different modes to improve the signal-to-noise ratio of diffuse correlation spectroscopy flow-oximeter measurements

Lian He, Yu Lin, Yu Shang, Brent Shelton, Guoqiang Yu

JBO, Vol. 18, Issue 03, 037001, (March 2013) https://doi.org/10.1117/12.10.1117/1.JBO.18.3.037001

KEYWORDS: Signal to noise ratio, Tissues, Multimode fibers, Single mode fibers, Optical fibers, Signal detection, Blood circulation, Sensors, Optical properties, Photons

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SPIE Journal Paper | 23 July 2012 Open Access

Errata: Noninvasive optical quantification of absolute blood flow, blood oxygenation, and oxygen consumption rate in exercising skeletal muscle

Katelyn Gurley, Yu Shang, Guoqiang Yu

JBO, Vol. 17, Issue 7, 079802, (July 2012) https://doi.org/10.1117/12.10.1117/1.JBO.17.7.079802

KEYWORDS: Blood circulation, Blood, Oxygen, Biomedical optics, Biomedical engineering, Error analysis, Data analysis

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SPIE Journal Paper | 12 July 2012 Open Access

Noninvasive optical quantification of absolute blood flow, blood oxygenation, and oxygen consumption rate in exercising skeletal muscle

Katelyn Gurley, Yu Shang, Guoqiang Yu

JBO, Vol. 17, Issue 7, 075010, (July 2012) https://doi.org/10.1117/12.10.1117/1.JBO.17.7.075010

KEYWORDS: Near infrared spectroscopy, Blood, Oxygen, Tissue optics, Hemodynamics, Data acquisition, Biomedical optics, Blood circulation, Signal detection, Tissues

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SPIE Journal Paper | 7 February 2012 Open Access

Near-infrared diffuse correlation spectroscopy in cancer diagnosis and therapy monitoring

Guoqiang Yu

JBO, Vol. 17, Issue 1, 010901, (February 2012) https://doi.org/10.1117/12.10.1117/1.JBO.17.1.010901

KEYWORDS: Tumors, Cancer, Blood circulation, Tissues, Photodynamic therapy, Near infrared, Near infrared spectroscopy, Tissue optics, Spectroscopy, Hemodynamics

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SPIE Journal Paper | 3 February 2012 Open Access

Noncontact diffuse correlation spectroscopy for noninvasive deep tissue blood flow measurement

Yu Lin, Lian He, Yu Shang, Guoqiang Yu

JBO, Vol. 17, Issue 1, 010502, (February 2012) https://doi.org/10.1117/12.10.1117/1.JBO.17.1.010502

KEYWORDS: Tissue optics, Tissues, Blood circulation, Sensors, Optical fibers, Liquids, Spectroscopy, Calibration, Temperature metrology, Lenses

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SPIE Journal Paper | 1 February 2011 Open Access

Intraoperative evaluation of revascularization effect on ischemic muscle hemodynamics using near-infrared diffuse optical spectroscopies

Guoqiang Yu, Yu Shang, Youquan Zhao, Ran Cheng, Lixin Dong, Sibu Saha

JBO, Vol. 16, Issue 02, 027004, (February 2011) https://doi.org/10.1117/12.10.1117/1.3533320

KEYWORDS: Hemodynamics, Blood circulation, Tissues, Surgery, Near infrared spectroscopy, Blood, Arteries, Fiber optics, Optical testing, Optical fibers

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SPIE Journal Paper | 1 May 2010 Open Access

Optical measurement of cerebral hemodynamics and oxygen metabolism in neonates with congenital heart defects

Turgut Durduran, Chao Zhou, Erin Buckley, Meeri Kim, Guoqiang Yu, Regine Choe, J. William Gaynor, Thomas Spray, Suzanne Durning, Stefanie Mason, Lisa Montenegro, Susan Nicolson, Robert Zimmerman, Mary Putt, Jiongjiong Wang, Joel Greenberg, John Detre, Arjun Yodh, Daniel Licht

JBO, Vol. 15, Issue 03, 037004, (May 2010) https://doi.org/10.1117/12.10.1117/1.3425884

KEYWORDS: Near infrared spectroscopy, Oxygen, Hemodynamics, Magnetic resonance imaging, Mode conditioning cables, Carbon monoxide, Optical testing, Heart, Blood, Cerebral blood flow

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SPIE Journal Paper | 1 May 2009 Open Access

Diffuse optical monitoring of hemodynamic changes in piglet brain with closed head injury

Chao Zhou, Stephanie Eucker, Turgut Durduran, Guoqiang Yu, Jill Ralston, Stuart Friess, Rebecca Ichord, Susan Margulies, Arjun Yodh

JBO, Vol. 14, Issue 03, 034015, (May 2009) https://doi.org/10.1117/12.10.1117/1.3146814

KEYWORDS: Injuries, Hemodynamics, Brain, Head, Blood, Fermium, Traumatic brain injury, Cerebral blood flow, Frequency modulation, Tissues

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SPIE Journal Paper | 1 September 2007 Open Access

Diffuse optical monitoring of blood flow and oxygenation in human breast cancer during early stages of neoadjuvant chemotherapy

Chao Zhou, Regine Choe, Natasha Shah, Turgut Durduran, Guoqiang Yu, Amanda Durkin, David Hsiang, Rita Mehta, John Butler, Albert Cerussi, Bruce Tromberg, Arjun Yodh

JBO, Vol. 12, Issue 05, 051903, (September 2007) https://doi.org/10.1117/12.10.1117/1.2798595

KEYWORDS: Tumors, Blood circulation, Oxygen, Tissues, Tissue optics, Breast, Hemodynamics, Breast cancer, Mode conditioning cables, Biomedical optics

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SPIE Journal Paper | 1 November 2006 Open Access

Noninvasive diffuse optical measurement of blood flow and blood oxygenation for monitoring radiation therapy in patients with head and neck tumors: a pilot study

Ulas Sunar, H. Quon, Turgut Durduran, Jun Zhang, Juan Du, Chao Zhou, Guoqiang Yu, Regine Choe, Alex Kilger, Robert Lustig, Laurie Loevner, Shoko Nioka, Britton Chance, Arjun Yodh

JBO, Vol. 11, Issue 06, 064021, (November 2006) https://doi.org/10.1117/12.10.1117/1.2397548

KEYWORDS: Tumors, Blood circulation, Neck, Tissue optics, Optical testing, Tissues, Radiotherapy, Head, Sensors, Blood

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Proceedings Article | 8 October 2005 Paper

Monitoring of radiation therapy response of head and neck tumors by non-invasive optical blood flow measurements

U. Sunar, H. Quon, J. Zhang, J. Du, T. Durduran, C. Zhou, G. Yu, A. Kilger, R. Lustig, L. Loevner, S. Nioka, A. Yodh, B. Chance

Proceedings Volume 5859, 58590I (2005) https://doi.org/10.1117/12.632838

KEYWORDS: Tumors, Blood circulation, Neck, Head, Radiotherapy, Optical testing, Sensors, Cancer, Positron emission tomography, Magnetic resonance imaging

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SPIE Journal Paper | 1 March 2005 Open Access

Time-dependent blood flow and oxygenation in human skeletal muscles measured with noninvasive near-infrared diffuse optical spectroscopies

Guoqiang Yu, Turgut Durduran, Gwen Lech, Chao Zhou, Britton Chance, Emile Mohler, Arjun Yodh

JBO, Vol. 10, Issue 02, 024027, (March 2005) https://doi.org/10.1117/12.10.1117/1.1884603

KEYWORDS: Tissues, Blood circulation, Oxygen, Blood, Hemodynamics, Near infrared spectroscopy, Diffuse reflectance spectroscopy, Control systems, Mode conditioning cables, Optical fibers

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Proceedings Article | 29 July 2003 Paper

Optimizing image reconstruction of tissue blood flow by diffuse correlation tomography

Chao Zhou, Turgut Durduran, Guoqiang Yu, Arjun Yodh

Proceedings Volume 4955, (2003) https://doi.org/10.1117/12.476883

KEYWORDS: Image restoration, Condition numbers, Sensors, Optical spheres, Blood circulation, Tissues, Tissue optics, Spherical lenses, Tomography, Spectroscopy

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Proceedings Article | 29 July 2003 Paper

Noninvasive cerebral hemoglobin oxygenation quantification of fetal sheep under hypoxic stress in utero using frequency-domain diffuse optical two-layer model

Regine Choe, Turgut Durduran, Guoqiang Yu, Mark Nijland, Peter Nathanielsz, Britton Chance, Arjun Yodh, Nirmala Ramanujam

Proceedings Volume 4955, (2003) https://doi.org/10.1117/12.478175

KEYWORDS: Blood, Near infrared spectroscopy, Hypoxia, Tissues, Head, Data modeling, Sensors, Arteries, Signal detection, Fetus

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Proceedings Article | 29 July 2003 Paper

Quantification of muscle oxygenation and flow of healthy volunteers during cuff occlusion of arm and leg flexor muscles and plantar flexion exercise

Turgut Durduran, Guoqiang Yu, Chao Zhou, Gwen Lech, Britton Chance, Arjun Yodh

Proceedings Volume 4955, (2003) https://doi.org/10.1117/12.476880

KEYWORDS: Blood circulation, Near infrared spectroscopy, Hemodynamics, Tissues, Oxygen, Spectroscopes, Blood oxygen saturation, Mode conditioning cables, Vascular diseases, Blood

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Proceedings Article | 29 July 2003 Paper

Hemodynamic measurements in rat brain and human muscle using diffuse near-infrared absorption and correlation spectroscopies

Guoqiang Yu, Turgut Durduran, D. Furuya, G. Lech, Chao Zhou, Britten Chance, J. H. Greenberg, Arjun Yodh

Proceedings Volume 4955, (2003) https://doi.org/10.1117/12.477345

KEYWORDS: Brain, Hemodynamics, Blood circulation, Ischemia, Near infrared spectroscopy, Tissues, Blood, Sensors, Tissue optics, Oxygen

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Measurement of concentration, oxygenation, and flow characteristics of blood cells can reveal information about tissue metabolism and functional heterogeneity. An improved multifunctional hybrid system has been built on the basis of our previous hybrid instrument that combines two near-infrared diffuse optical techniques to simultaneously monitor the changes of blood flow, total hemoglobin concentration (THC) and blood oxygen saturation (StO2). Diffuse correlation spectroscopy (DCS) monitors blood flow (BF) by measuring the optical phase shifts caused by moving blood cells, while diffuse photon density wave spectroscopy (DPDW) measures tissue absorption and scattering. Higher spatial resolution, higher data acquisition rate and higher dynamic range of the improved system allow us to monitor rapid hemodynamic changes in rat brain and human muscles. We have designed two probes with different source-detector pairs and different separations for the two types of experiments. A unique non-contact probe mounted on the back of a camera, which allows continuous measurements without altering the blood flow, was employed to in vivo monitor the metabolic responses in rat brain during KCl induced cortical spreading depression (CSD). A contact probe was used to measure changes of blood flow and oxygenation in human muscle during and after cuff occlusion or exercise, where the non-contact probe is not appropriate for monitoring the moving target. The experimental results indicate that our multifunctional hybrid system is capable of in vivo and non-invasive monitoring of the hemodynamic changes in different tissues (smaller tissues in rat brain, larger tissues in human muscle) under different conditions (static versus moving). The time series images of flow during CSD obtained by our technique revealed spatial and temporal hemodynamic changes in rat brain. Two to three fold longer recovery times of flow and oxygenation after cuff occlusion or exercise from calf flexors in a patient with peripheral vascular disease (PVD) were found.

Proceedings Article | 13 June 2003 Paper

Noninvasive monitoring hemodynamic responses in RIF tumors during and after PDT

Guoqiang Yu, Turgut Durduran, Theresa Busch, Hsing-Wen Wang, Chao Zhou, H. Mark Saunders, Chandra Sehgal, Arjun Yodh

Proceedings Volume 4952, (2003) https://doi.org/10.1117/12.474101

KEYWORDS: Photodynamic therapy, Tumors, Blood circulation, Oxygen, Spectroscopy, Tissue optics, Doppler effect, Hemodynamics, Ultrasonography, Absorption

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