Dr. Warren S. Grundfest Profile

Dr. Warren S. Grundfest

Deceased at UCLA Samueli School of Engineering

SPIE Involvement:

Track Chair | Author | Editor

Publications (105)

Proceedings Article | 8 March 2019 Paper

Dynamic optical contrast imaging (DOCI): system theory for rapid, wide-field, multispectral optical imaging using fluorescence lifetime contrast mechanism

Harrison Cheng, Yao Xie, Peter Pellionisz, Aidan Pearigen, Khuzaima Rangwalla, Oscar Stafsudd, Zachary Taylor, Maie St. John, Warren Grundfest

Proceedings Volume 10951, 109512T (2019) https://doi.org/10.1117/12.2513823

KEYWORDS: Luminescence, Tissues, Imaging systems, Data modeling, Convolution, Optical imaging, Mathematical modeling, Signal to noise ratio, Systems modeling, Statistical modeling

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Proceedings Article | 14 March 2018 Presentation

Optimizing dynamic optical contrast imaging: signal characterization in the head and neck animal model (Conference Presentation)

Karam Badran, Harrison Cheng, Shijun Sung, Peter Pellionisz, Zach Taylor, Warren Grundfest, Maie St John

Proceedings Volume 10469, 1046914 (2018) https://doi.org/10.1117/12.2296903

KEYWORDS: Animal model studies, Optical imaging, Head, Neck, Tissues, Tissue optics, Ultraviolet radiation, Tongue, Tumors, Signal analysis

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Proceedings Article | 19 February 2018 Paper

Identifying viscoelastic parameters of tissue specimens using Hertz contact mechanics

Nikan Namiri, Ashkan Maccabi, Neha Bajwa, Karam Badran, Maie St. John, Zachary Taylor, Warren Grundfest, George Saddik

Proceedings Volume 10486, 1048606 (2018) https://doi.org/10.1117/12.2289831

KEYWORDS: Tissues, Liver, Mechanics, Acoustics, Surgery, Image resolution, Tumors, Animal model studies, Statistical analysis

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Proceedings Article | 12 February 2018 Paper

Optimizing signal output: effects of viscoelasticity and difference frequency on vibroacoustic radiation of tissue-mimicking phantoms

Nikan Namiri, Ashkan Maccabi, Neha Bajwa, Karam Badran, Zachary Taylor, Maie St. John, Warren Grundfest, George Saddik

Proceedings Volume 10484, 104840N (2018) https://doi.org/10.1117/12.2291382

KEYWORDS: Tissues, Acoustics, Tumors, Head, Neck, Transducers, Cancer, Confocal microscopy, Signal attenuation, Signal to noise ratio

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SPIE Journal Paper | 3 April 2017 Open Access

Special Section Guest Editorial: Brain Mapping and Therapeutics

Shouleh Nikzad, Yu Chen, Vassiliy Tsytsarev, Babak Kateb, Warren Grundfest

NPh, Vol. 4, Issue 01, 011001, (April 2017) https://doi.org/10.1117/12.10.1117/1.NPh.4.1.011001

KEYWORDS: Brain, Brain mapping, Neurophotonics, Neuroimaging, Tissue optics, Medicine, Sensors, Neuroscience, Optical coherence tomography, Tumors

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Proceedings Article | 26 May 2016 Paper

Evolution of THz impulse imaging radar to 1550nm photoconductive switches

E. Brown, W.-D. Zhang, A. Feldman, T. Harvey, R. Mirin, S. Sung, W. Grundfest, Z. Taylor

Proceedings Volume 9854, 98540L (2016) https://doi.org/10.1117/12.2224919

KEYWORDS: Terahertz radiation, Switches, Erbium, Gallium arsenide, Absorption, Signal attenuation, Nanoparticles, Pyroelectric detectors, Antennas, Spectrometers

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Proceedings Article | 3 May 2016 Presentation

In situ monitoring of surgical flap viability using THz imaging (Conference Presentation)

Neha Bajwa, Shijun Sung, Warren Grundfest, Zachary Taylor

Proceedings Volume 9706, 97060A (2016) https://doi.org/10.1117/12.2218572

KEYWORDS: Terahertz radiation, Tissues, Surgery, Blood, Tumors, Reflectivity, Head, Neck, Abdomen, Blood circulation

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Proceedings Article | 26 April 2016 Presentation

Corneal tissue water content mapping with THz imaging: preliminary clinical results (Conference Presentation)

Shijun Sung, Neha Bajwa, Sophie Deng, Zachary Taylor, Warren Grundfest

Proceedings Volume 9706, 97060B (2016) https://doi.org/10.1117/12.2218575

KEYWORDS: Cornea, Terahertz radiation, Tissues, Injuries, Ultrasonography, Optical coherence tomography, Dielectrics, Optical design, Data acquisition, In vivo imaging

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Proceedings Article | 26 April 2016 Presentation

Visualization of vasodynamics using THz imaging with applications to allergy testing (Conference Presentation)

Shijun Sung, Neha Bajwa, Warren Grundfest, Zachary Grundfest

Proceedings Volume 9706, 97060C (2016) https://doi.org/10.1117/12.2218576

KEYWORDS: Terahertz radiation, Tissues, Skin, Visualization, Reflectivity, Natural surfaces, Nose, Diagnostics, Eye, Tissue optics

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SPIE Journal Paper | 23 November 2015 Open Access

Imaging autofluorescence temporal signatures of the human ocular fundus in vivo

Asael Papour, Zachary Taylor, Oscar Stafsudd, Irena Tsui, Warren Grundfest

JBO, Vol. 20, Issue 11, 110505, (November 2015) https://doi.org/10.1117/12.10.1117/1.JBO.20.11.110505

KEYWORDS: Light emitting diodes, Retina, In vivo imaging, Luminescence, Cameras, Eye, Imaging systems, Fluorescence lifetime imaging, Tissue optics, Microscopy

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Proceedings Article | 8 September 2015 Paper

THz polarization difference imaging of aqueous targets

Shijun Sung, Neha Bajwa, Lucia Ramirez, Warren Grundfest, Zachary Taylor

Proceedings Volume 9585, 95850W (2015) https://doi.org/10.1117/12.2189318

KEYWORDS: Terahertz radiation, Reflectivity, Polarization, Tissues, Imaging systems, Signal to noise ratio, Water, Sensors, Dielectric polarization, Calibration

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Proceedings Article | 31 August 2015 Paper

Exploration of the effects of burn parameters on THz wound imaging

Neha Bajwa, Shijun Sung, Michael Fishbein, Warren Grundfest, Zachary Taylor

Proceedings Volume 9585, 95850T (2015) https://doi.org/10.1117/12.2189295

KEYWORDS: Terahertz radiation, Tissues, Reflectivity, Quartz, In vivo imaging, Injuries, Electromagnetism, Dielectrics, Medical imaging, Animal model studies

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Proceedings Article | 28 April 2015 Paper

Preliminary results of non-contact THz imaging of cornea

Shijun Sung, James Garritano, Neha Bajwa, Sophie Deng, Jean-Pierre Hubschman, Warren Grundfest, Zachary Taylor

Proceedings Volume 9362, 93620C (2015) https://doi.org/10.1117/12.2086866

KEYWORDS: Cornea, Terahertz radiation, Tissues, Reflectivity, Mirrors, Water, Eye, Imaging systems, Sensors, In vivo imaging

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Proceedings Article | 19 March 2015 Paper

Real time early detection imaging system of failed wounds and heterotopic ossification using unique Raman signatures

Asael Papour, Zach Taylor, Oscar Stafsudd, Warren Grundfest

Proceedings Volume 9417, 94171G (2015) https://doi.org/10.1117/12.2082093

KEYWORDS: Raman spectroscopy, Bone, Imaging systems, Signal detection, In vivo imaging, Tissues, Luminescence, Raman scattering, Optical filters, Spectroscopy

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Proceedings Article | 5 September 2014 Paper

In vivo confirmation of hydration based contrast mechanisms for terahertz medical imaging using MRI

Neha Bajwa, Shijun Sung, James Garritano, Bryan Nowroozi, Priyamvada Tewari, Daniel Ennis, Jeffery Alger, Warren Grundfest, Zachary Taylor

Proceedings Volume 9199, 91990U (2014) https://doi.org/10.1117/12.2060115

KEYWORDS: Terahertz radiation, Tissues, Magnetic resonance imaging, Reflectivity, Skin, In vivo imaging, Imaging systems, Abdomen, Medical imaging, Water

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Proceedings Article | 5 September 2014 Paper

THz optical design considerations and optimization for medical imaging applications

Shijun Sung, James Garritano, Neha Bajwa, Bryan Nowroozi, Nuria Llombart, Warren Grundfest, Zachary Taylor

Proceedings Volume 9199, 91990S (2014) https://doi.org/10.1117/12.2062403

KEYWORDS: Mirrors, Terahertz radiation, Imaging systems, Distortion, Polarization, Off axis mirrors, Collimation, Optical design, Calibration, Medical imaging applications

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Proceedings Article | 5 September 2014 Paper

THz imaging studies of painted samples to guide cultural heritage investigations at the Enkleistra of St. Neophytos in Paphos, Cyprus

Roxanne Radpour, Neha Bajwa, James Garritano, Shijun Sung, Magdalena Balonis-Sant, Priyamvada Tewari, Warren Grundfest, Ioanna Kakoulli, Zachary Taylor

Proceedings Volume 9199, 91990Q (2014) https://doi.org/10.1117/12.2062228

KEYWORDS: Terahertz radiation, Imaging systems, Cultural heritage, Lead, Scattering, Calcium, Sensors, Nondestructive evaluation, Medical imaging, Spatial resolution

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Proceedings Article | 2 April 2014 Paper

Optical design for translation of THz medical imaging technology

Zachary Taylor, Shijun Sung, James Garritano, Neha Bajwa, Bryan Nowroozi, Nuria Llombart, Priyamvada Tewari, Warren Grundfest

Proceedings Volume 8985, 89850H (2014) https://doi.org/10.1117/12.2045638

KEYWORDS: Mirrors, Terahertz radiation, Polarization, Sensors, Off axis mirrors, Medical imaging, Objectives, Collimation, Imaging systems, Optical design

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Proceedings Article | 20 March 2014 Paper

Ex vivo viscoelastic characterization of head and neck tissue abnormalities using ultrasound-stimulated vibro-acoustography (USVA)

Ashkan Maccabi, James Garritano, Armin Arshi, George Saddik, Bobby Tajudeen, Maie St. John, Warren Grundfest, Zachary Taylor

Proceedings Volume 9040, 904006 (2014) https://doi.org/10.1117/12.2043691

KEYWORDS: Tissues, Head, Neck, Acoustics, Surgery, Tumors, Optical coherence tomography, Ultrasonography, Acoustic emission, Medicine

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Proceedings Article | 13 March 2014 Paper

THz impulse radar for biomedical sensing: nonlinear system behavior

E. Brown, Shijun Sung, W. Grundfest, Z. Taylor

Proceedings Volume 8941, 89411E (2014) https://doi.org/10.1117/12.2044061

KEYWORDS: Terahertz radiation, Signal to noise ratio, Radar, Switches, Receivers, Diodes, Sensors, Complex systems, Tissues, Transmitters

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SPIE Journal Paper | 12 June 2013 Open Access

Optical imaging for brain tissue characterization using relative fluorescence lifetime imaging

Asael Papour, Zachary Taylor, Adria Sherman, Desiree Sanchez, Gregory Lucey, Linda Liau, Oscar Stafsudd, William Yong, Warren Grundfest

JBO, Vol. 18, Issue 06, 060504, (June 2013) https://doi.org/10.1117/12.10.1117/1.JBO.18.6.060504

KEYWORDS: Tissues, Brain, Tissue optics, Luminescence, Neuroimaging, Fluorescence lifetime imaging, Imaging systems, Light emitting diodes, Calibration, Optical imaging

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Proceedings Article | 24 April 2013 Paper

Reflective terahertz (THz) imaging: system calibration using hydration phantoms

Neha Bajwa, James Garritano, Yoon Kyung Lee, Priyamvada Tewari, Shijun Sung, Ashkan Maccabi, Bryan Nowroozi, Meghedi Babakhanian, Sajan Sanghvi, Rahul Singh, Warren Grundfest, Zachary Taylor

Proceedings Volume 8585, 85850W (2013) https://doi.org/10.1117/12.2001913

KEYWORDS: Terahertz radiation, Reflectivity, Tissues, Imaging systems, Calibration, In vivo imaging, Water, Aluminum, Quartz, Skin

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Proceedings Article | 27 March 2013 Paper

Active THz medical imaging using broadband direct detection

Zachary Taylor, James Garritano, Priyamvada Tewari, Eric Diebold, Shijun Sung, Neha Bajwa, Bryan Nowroozi, Alexander Stojadinovic, Nuria Llombart, Elliott Brown, Warren Grundfest

Proceedings Volume 8624, 862403 (2013) https://doi.org/10.1117/12.2012070

KEYWORDS: Terahertz radiation, Tissues, Imaging systems, Sensors, Switches, Medical imaging, Electro optics, Reflectivity, Skin, Imaging spectroscopy

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Proceedings Article | 22 March 2013 Paper

Normalized fluorescence lifetime imaging for tumor identification and margin delineation

Adria Sherman, Asael Papour, Siddharth Bhargava, Maie A. St. John, William Yong, Zach Taylor, Warren Grundfest, Oscar Stafsudd

Proceedings Volume 8572, 85721H (2013) https://doi.org/10.1117/12.2013414

KEYWORDS: Tissues, Luminescence, Tumors, Bandpass filters, Collagen, Imaging systems, Glasses, Cancer, Head, Neck

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Fluorescence lifetime imaging microscopy (FLIM) is a technique that has been proven to produce quantitative and qualitative differentiation and identification of substances with good specificity and sensitivity based on lifetime extracted information. This technique has shown the ability to also differentiate between a wide range of tissue types to identify malignant from benign tissue in vivo and ex vivo. However, the complexity, long duration and effort required to generate this information has limited the adoption of these techniques in a clinical setting. Our group has developed a time-resolved imaging system (patent pending) that does not require the extraction of lifetimes or use of complex curve fitting algorithms to display the needed information. The technique, entitled Lifetime Fluorescence Imaging (LFI, or NoFYI), converts fluorescence lifetime decay information directly into visual contrast. Initial studies using Fluorescein and Rhodamine-B demonstrated the feasibility of this approach. Subsequent studies demonstrated the ability to separate collagen and elastin powders. The technique uses nanosecond pulsed UV LEDs at 375 nm for average illumination intensities of ~4.5 μW on the tissue surface with detection by a gated CCD camera. To date, we have imaged 11 surgical head and neck squamous cell carcinoma and brain cancer biopsy specimens including 5 normal and 6 malignant samples. Images at multiple wavelengths clearly demonstrate differentiation between benign and malignant tissue, which was later confirmed by histology. Contrast was obtained between fluorophores with 35 μm spatial resolution and an SNR of ~30 dB allowing us to clearly define tumor margins in these highly invasive cancers. This method is capable of providing both anatomical and chemical information for the pathologist and the surgeon. These results suggest that this technology has a possible role in identifying tumors in tissue specimens and detecting tumor margins during procedures.

Proceedings Article | 23 February 2013 Paper

Reflectivity measurements of water and dioxane mixtures using a 100 GHz Gunn diode source

Ashkan Maccabi, David Bennett, Neha Bajwa, Priyamvada Tewari, Shijun Sung, Warren Grundfest, Zachary Taylor

Proceedings Volume 8585, 85850X (2013) https://doi.org/10.1117/12.2003181

KEYWORDS: Terahertz radiation, Data modeling, Dielectrics, Reflectivity, Tissues, Diodes, Water, Magnesium, Sensing systems, Systems modeling

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Proceedings Article | 18 October 2012 Paper

Fast-scanning THz medical imaging system for clinical application

Shijun Sung, Neha Bajwa, Nuhba Fokwa, Priyamvada Tewari, Rahul Singh, Martin Culjat, Bryan Nowroozi, Warren Grundfest, Zachary Taylor

Proceedings Volume 8496, 84960S (2012) https://doi.org/10.1117/12.946013

KEYWORDS: Terahertz radiation, Imaging systems, Mirrors, Tissues, Objectives, Medical imaging, Lenses, Image acquisition, Target acquisition, Reflectivity

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Proceedings Article | 15 October 2012 Paper

Reflective THz and MR imaging of burn wounds: a potential clinical validation of THz contrast mechanisms

Neha Bajwa, Bryan Nowroozi, Shijun Sung, James Garritano, Ashkan Maccabi, Priyamvada Tewari, Martin Culjat, Rahul Singh, Jeffry Alger, Warren Grundfest, Zachary Taylor

Proceedings Volume 8496, 84960X (2012) https://doi.org/10.1117/12.934449

KEYWORDS: Terahertz radiation, Magnetic resonance imaging, Tissues, Skin, In vivo imaging, Reflectivity, Visualization, Injuries, Medical imaging, Natural surfaces

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SPIE Journal Paper | 21 September 2012 Open Access

Assessment of corneal hydration sensing in the terahertz band: in vivo results at 100 GHz

David Bennett, Zachary Taylor, Priyamvada Tewari, Sijun Sung, Ashkan Maccabi, Rahul Singh, Martin Culjat, Warren Grundfest, Jean-Pierre Hubschman, Elliott Brown

JBO, Vol. 17, Issue 9, 097008, (September 2012) https://doi.org/10.1117/12.10.1117/1.JBO.17.9.097008

KEYWORDS: Cornea, Terahertz radiation, Tissues, In vivo imaging, Water, Reflectivity, Dielectrics, Spectroscopy, Skin, Surgery

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SPIE Journal Paper | 6 April 2012 Open Access

In vivo terahertz imaging of rat skin burns

Priyamvada Tewari, Neha Bajwa, Rahul Singh, Martin Culjat, Warren Grundgest, Zachary Taylor, Colin Kealey, David Bennett, Kelli Barnett, Alexander Stojadinovic

JBO, Vol. 17, Issue 04, 040503, (April 2012) https://doi.org/10.1117/12.10.1117/1.JBO.17.4.040503

KEYWORDS: Skin, Terahertz radiation, Reflectivity, Tissues, Injuries, In vivo imaging, Abdomen, Millimeter wave imaging, Medical imaging, Imaging systems

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SPIE Journal Paper | 7 March 2012 Open Access

Endomicroscopy Technologies and Biomedical Applications

Xingde Li, Warren Grundfest

JBO, Vol. 17, Issue 02, 021101, (March 2012) https://doi.org/10.1117/12.10.1117/1.JBO.17.2.021101

KEYWORDS: Endomicroscopy, Biomedical optics, Biopsy, Endoscopes, Luminescence, Confocal microscopy, Fiber optics, Surveillance, In vivo imaging, Colon

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Proceedings Article | 6 March 2012 Paper

Advances in biomedical imaging using THz technology with applications to burn-wound assessment

Priyamvada Tewari, Colin Kealey, Shijun Sung, Ashkan Maccabi, Neha Bajwa, Rahul Singh, Martin Culjat, Alexander Stojadinovic, Warren Grundfest, Zachary Taylor

Proceedings Volume 8261, 82610T (2012) https://doi.org/10.1117/12.915987

KEYWORDS: Terahertz radiation, Tissues, Imaging systems, Injuries, Reflectivity, Skin, Diagnostics, Biomedical optics, Medical imaging, Sensors

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Proceedings Article | 28 February 2012 Paper

In vitro cell system for studying molecular mechanisms of action associated with low intensity focused ultrasound

Meghedi Babakhanian, Richard Fan, Amit Mulgaonkar, Rahul Singh, Martin Culjat, Shahab Danesh, Ligia Toro, Warren Grundfest, William Melega

Proceedings Volume 8214, 82140S (2012) https://doi.org/10.1117/12.911602

KEYWORDS: Ultrasonography, Brain, In vivo imaging, Acoustics, In vitro testing, Potassium, Modulation, Molecular mechanisms, Transducers, Chemical elements

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Proceedings Article | 28 February 2012 Paper

Bacterial biofilm disruption using laser-generated shockwaves

Artemio Navarro, Zachary Taylor, Anthony Matolek, Ahuva Weltman, Vidyunmala Ramaprasad, Sean Huang, David Beenhouwer, David Haake, Vijay Gupta, Warren Grundfest

Proceedings Volume 8214, 82141H (2012) https://doi.org/10.1117/12.908661

KEYWORDS: Bacteria, Glasses, Ultrasonography, Titanium, Laser energy, Interfaces, Medicine, Wound healing, Ultrasonics, Bone

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Proceedings Article | 17 September 2011 Paper

A scanned beam THz imaging system for medical applications

Zachary Taylor, Wenzao Li, Jon Suen, Priyamvada Tewari, David Bennett, Neha Bajwa, Elliott Brown, Martin Culjat, Warren Grundfest, Rahul Singh

Proceedings Volume 8119, 811906 (2011) https://doi.org/10.1117/12.894362

KEYWORDS: Terahertz radiation, Mirrors, Imaging systems, Beam splitters, Sensors, Objectives, Medical imaging, Signal to noise ratio, Image acquisition, Target acquisition

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SPIE Journal Paper | 1 August 2011 Open Access

Quasi-real-time fluorescence imaging with lifetime dependent contrast

Pei-Chi Jiang, Oscar Stafsudd, Warren Grundfest

JBO, Vol. 16, Issue 08, 086001, (August 2011) https://doi.org/10.1117/12.10.1117/1.3609229

KEYWORDS: Luminescence, Image processing, Tissues, Collagen, Fluorescence lifetime imaging, Time resolved spectroscopy, Cameras, Calibration, Signal to noise ratio, Ultraviolet light emitting diodes

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SPIE Journal Paper | 1 May 2011 Open Access

Terahertz sensing in corneal tissues

David Bennett, Zachary Taylor, Priyamvada Tewari, Rahul Singh, Martin Culjat, Warren Grundfest, Daniel Sassoon, R. Duncan Johnson, Jean-Pierre Hubschman, Elliott Brown

JBO, Vol. 16, Issue 05, 057003, (May 2011) https://doi.org/10.1117/12.10.1117/1.3575168

KEYWORDS: Terahertz radiation, Cornea, Tissues, Water, Reflectivity, Imaging systems, Spectroscopy, Eye, Imaging spectroscopy, Surgery

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Proceedings Article | 18 April 2011 Paper

Reflective measurement of water concentration using millimeter wave illumination

Shijun Sung, David Bennett, Zachary Taylor, Neha Bajwa, Priyamvada Tewari, Ashkan Maccabi, Martin Culjat, Rahul Singh, Warren Grundfest

Proceedings Volume 7984, 798434 (2011) https://doi.org/10.1117/12.883257

KEYWORDS: Reflectivity, Terahertz radiation, Water, Extremely high frequency, Skin, Tissues, Liver, Injuries, Cornea, Diodes

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Proceedings Article | 24 February 2011 Paper

Terahertz time-lapse imaging of hydration in physiological tissues

David Bennett, Zachary Taylor, Neha Bajwa, Priyamvada Tewari, Ashkan Maccabi, Shijun Sung, Rahul Singh, Martin Culjat, Warren Grundfest, Elliott Brown

Proceedings Volume 7938, 793808 (2011) https://doi.org/10.1117/12.882962

KEYWORDS: Terahertz radiation, Tissues, Cornea, Skin, Water, Imaging systems, Reflectivity, Visualization, Spectroscopy, Binary data

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Proceedings Article | 12 March 2010 Paper

Accurate step-FMCW ultrasound ranging and comparison with pulse-echo signaling methods

Shyam Natarajan, Rahul Singh, Michael Lee, Brian Cox, Martin Culjat, Warren Grundfest, Hua Lee

Proceedings Volume 7629, 76290D (2010) https://doi.org/10.1117/12.845539

KEYWORDS: Ranging, Ultrasonography, Transducers, Acoustics, Signal to noise ratio, Signal processing, Signal detection, Fourier transforms, Signal attenuation, Receivers

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Proceedings Article | 12 March 2010 Paper

Fabrication of a conformal ring-annular ultrasound array

Aaron Dann, David Bennett, Rahul Singh, Jean-Jacques Lemaire, Warren Grundfest, Martin Culjat

Proceedings Volume 7629, 76290R (2010) https://doi.org/10.1117/12.844634

KEYWORDS: Transducers, Ultrasonography, Chemical elements, Silicon, Ferroelectric materials, Semiconducting wafers, Imaging arrays, Thin films, Deep reactive ion etching, Silicon films

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Proceedings Article | 12 March 2010 Paper

Designing multistatic ultrasound imaging systems using software analysis

Michael Lee, Rahul Singh, Martin Culjat, Scott Stubbs, Shyam Natarajan, Elliott Brown, Warren Grundfest, Hua Lee

Proceedings Volume 7629, 76290S (2010) https://doi.org/10.1117/12.845581

KEYWORDS: Transducers, Ultrasonography, Data modeling, Imaging systems, Image processing, Reconstruction algorithms, Imaging arrays, Data acquisition, Image acquisition, MATLAB

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Proceedings Article | 23 February 2010 Paper

THz imaging of skin hydration: motivation for the frequency band

Rahul Singh, Zachary Taylor, Priyamvada Tewari, David Bennett, Martin Culjat, Hua Lee, Elliott Brown, Warren Grundfest

Proceedings Volume 7555, 755513 (2010) https://doi.org/10.1117/12.845820

KEYWORDS: Terahertz radiation, Skin, Scattering, Imaging systems, Reflectivity, Spatial resolution, Signal attenuation, Absorption, Dielectrics, Tissues

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Proceedings Article | 23 February 2010 Paper

Step-FMCW signaling and target detection for ultrasound imaging systems with conformal transducer arrays

Shyam Natarajan, Rahul Singh, Michael Lee, Brian Cox, Martin Culjat, Hua Lee, Warren Grundfest

Proceedings Volume 7555, 75550M (2010) https://doi.org/10.1117/12.845379

KEYWORDS: Transducers, Ultrasonography, Signal detection, Imaging systems, Target detection, Image restoration, Acoustics, Signal processing, Medical imaging, Receivers

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Proceedings Article | 8 April 2009 Paper

A conformal ultrasound transducer array featuring microfabricated polyimide joints

David Bennett, Martin Culjat, Brian Cox, Aaron Dann, Kimani Williams, Hua Lee, Elliott Brown, Warren Grundfest, Rahul Singh

Proceedings Volume 7295, 72951W (2009) https://doi.org/10.1117/12.815498

KEYWORDS: Transducers, Ultrasonography, Silicon, Ferroelectric materials, Silicon films, Thin films, Etching, Polymers, Chemical elements, Microfabrication

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Proceedings Article | 13 March 2009 Paper

Waveform synthesis for the design and image reconstruction of step FMCW ultrasound imaging systems with conformal transducer arrays

Michael Lee, Rahul Singh, Martin Culjat, Shyam Natarajan, Brian Cox, Elliott Brown, Warren Grundfest, Hua Lee

Proceedings Volume 7265, 72650C (2009) https://doi.org/10.1117/12.812206

KEYWORDS: Ultrasonography, Transducers, Imaging systems, Image restoration, Imaging arrays, Signal detection, Algorithm development, Signal attenuation, Data acquisition, Image acquisition

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Proceedings Article | 25 February 2009 Paper

Role of collagen in terahertz absorption in skin

Priyamvada Tewari, Martin Culjat, Zachary Taylor, Jonathan Suen, Benjamin Burt, Hua Lee, Elliott Brown, Warren Grundfest, Rahul Singh

Proceedings Volume 7169, 71691A (2009) https://doi.org/10.1117/12.816433

KEYWORDS: Skin, Terahertz radiation, Collagen, Reflectivity, Absorption, Aluminum, Tissues, Proteins, Imaging systems, Raster graphics

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Proceedings Article | 15 April 2008 Paper

THz imaging based on water-concentration contrast

Z. Taylor, R. Singh, M. Culjat, J. Suen, W. Grundfest, E. Brown

Proceedings Volume 6949, 69490D (2008) https://doi.org/10.1117/12.785337

KEYWORDS: Terahertz radiation, Skin, Reflectivity, Imaging systems, Switches, Signal to noise ratio, Tissues, Sensors, Metals, Aluminum

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Proceedings Article | 17 June 2002 Paper

Excimer-laser-assisted thrombolysis: the effect of laser fluence, repetition rate, and catheter size

Thanassis Papaioannou, Oleg Sorokoumov, Kevin Taylor, Warren Grundfest

Proceedings Volume 4609, (2002) https://doi.org/10.1117/12.432075

KEYWORDS: Laser ablation, Excimer lasers, In vitro testing, Laser therapeutics, Laser safety, Tissues, Natural surfaces, Biomedical optics, Medical research, Laser applications

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Proceedings Article | 17 June 2002 Paper

Particulate debris analysis during excimer laser thrombolysis: an in-vitro study

Thanassis Papaioannou, Jeff Levisman, Oleg Sorokoumov, Kevin Taylor, Shane Pitzer, Warren Grundfest

Proceedings Volume 4609, (2002) https://doi.org/10.1117/12.432077

KEYWORDS: Particles, Excimer lasers, Laser ablation, Optical filters, In vitro testing, Blood, Laser therapeutics, Veins, Biomedical optics, Medical research

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Proceedings Article | 13 June 2002 Paper

Update on laser vision correction using wavefront analysis with the CustomCornea system and LADARVision 193-nm excimer laser

Ezra Maguen, James Salz, Marguerite McDonald, George Pettit, Thanassis Papaioannou, Warren Grundfest

Proceedings Volume 4611, (2002) https://doi.org/10.1117/12.470588

KEYWORDS: Wavefront analysis, Eye, Laser vision correction, Excimer lasers, LASIK, Contrast sensitivity, Wavefronts, Visualization, Monochromatic aberrations, Clinical trials

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Proceedings Article | 13 June 2002 Paper

Spatiotemporal temperature profiling of corneal surface during LTK

Thanassis Papaioannou, Ezra Maguen, Warren Grundfest

Proceedings Volume 4611, (2002) https://doi.org/10.1117/12.470582

KEYWORDS: Thermal modeling, Thermography, Cameras, In vitro testing, Eye models, Cornea, Tissues, Profiling, Temporal resolution, Medical research

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Accurate prediction of LTK treatments requires refined thermal corneal models which necessitate precise input parameters. The overall objective of this study was to provide detailed information on the spatiotemporal temperature profile of the corneal surface, during in-vitro thermal keratoplasty. LTK was performed in-vitro on freshly harvested porcine eyes (N equals 16) with the Sunrise Technologies corneal shaping system (Model SUN 1000). Spatiotemporal thermal imaging of the irradiated corneas were obtained with a short wave Inframetrics thermal camera (Model PM290). Images were obtained at 8-bits resolution, with ~100 microns spatial and ~17 msec temporal resolution respectively. Treatment pattern consisted of eight spots at 6 mm zone, while lasing was conducted at settings of either 100 mJ and 15 pulses (N equals 8), or 260 mJ and 7 pulses (N equals 8). Temporal and spatial variation of the corneal surface temperatures were calculated at locations of importance to LTK. At the laser spot, temperature profiles consisted of transients coinciding approximately with the laser pulses. Maximum transient temperatures observed were 98.0+/- 4.6 degree(s)C for the high and 56.3+/- 2.6 degree(s)C for the low energy respectively. These temperature transients were superimposed on an envelope of lower-slowly varying temperatures. The maximum temperatures observed for this temperature envelope, were 51.8+/- 3.4 degree(s)C for the high and 35.4+/- 3.4 degree(s)C for the low energy respectively. The evolution of either the maximum temperature transients or the lower temperature envelope, followed exponential growth of the form: T equals A * exp(B*t). Maximum temperatures at locations 0.5 mm and 1 mm away from the laser spot, reached 25.7 degree(s)C and 23.3 degree(s)C for the low energy, and 34 degree(s)C and 25.6 degree(s)C for the high energy settings respectively. Temperature decay constants were approximately 2 to 3 sec, while the spatial temperature profile at the laser spot extended more than 2 mm at 2.5 sec post irradiation. The data obtained may help to refine corneal thermal modeling during LTK, and thus improve predictability of current or future-modified-treatments.

Proceedings Article | 13 May 2002 Paper

Thermal imaging of brain tumors in a rat glioma model

Thanassis Papaioannou, Reid Thompson, Babak Kateb, Oleg Sorokoumov, Warren Grundfest, Keith Black

Proceedings Volume 4615, (2002) https://doi.org/10.1117/12.466653

KEYWORDS: Tumors, Brain, Thermography, Neuroimaging, Thermal modeling, Cameras, Biomedical optics, Tissues, Animal model studies, Medical research

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SPIE Journal Paper | 1 July 2001 Open Access

Ablation spectra of the human cornea

David Cohen, Roy Chuck, Gregory Bearman, Peter McDonnell, Warren Grundfest

JBO, Vol. 6, Issue 03, (July 2001) https://doi.org/10.1117/12.10.1117/1.1380670

KEYWORDS: Cornea, Luminescence, Laser ablation, Tissues, Excimer lasers, Principal component analysis, Laser tissue interaction, Surgery, Laser therapeutics, Ultraviolet radiation

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Proceedings Article | 21 May 2001 Paper

Arterial fluorescent components involved in atherosclerotic plaque instability: differentiation by time-resolved fluorescence spectroscopy

Laura Marcu, Warren Grundfest, Jean-Michel Maarek

Proceedings Volume 4244, (2001) https://doi.org/10.1117/12.427829

KEYWORDS: Collagen, Luminescence, Proteins, Time resolved spectroscopy, Laser induced fluorescence, Spectroscopy, Fluorescence spectroscopy, Tissues, Nitrogen lasers, Foam

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SPIE Journal Paper | 1 July 2000 Open Access

Consequences of scattering for spectral imaging of turbid biological tissue

Mark Arnoldussen, David Cohen, Gregory Bearman, Warren Grundfest

JBO, Vol. 5, Issue 03, (July 2000) https://doi.org/10.1117/12.10.1117/1.430000

KEYWORDS: Tissue optics, Scattering, Imaging spectroscopy, Backscatter, Natural surfaces, Reflectors, Imaging systems, Tissues, Systems modeling, Sensors

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Proceedings Article | 19 April 2000 Paper

Characterization of type I, II, III, IV, and V collagens by time-resolved laser-induced fluorescence spectroscopy

Laura Marcu, David Cohen, Jean-Michel Maarek, Warren Grundfest

Proceedings Volume 3917, (2000) https://doi.org/10.1117/12.382720

KEYWORDS: Collagen, Luminescence, Tissues, Laser induced fluorescence, Skin, Time resolved spectroscopy, Fluorescence spectroscopy, Laser spectroscopy, Cartilage, Spectroscopy

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Proceedings Article | 19 April 2000 Paper

Global analysis of arterial fluorescence decay spectra

Jean-Michel Maarek, Warren Grundfest, Laura Marcu

Proceedings Volume 3917, (2000) https://doi.org/10.1117/12.382722

KEYWORDS: Luminescence, Tissues, Signal to noise ratio, Statistical modeling, Statistical analysis, Time resolved spectroscopy, Arteries, Pulsed laser operation, Deconvolution, Nitrogen lasers

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Proceedings Article | 14 March 2000 Paper

Imaged backscatter from three-dimensional tissue structure

Mark Arnoldussen, David Cohen, Gregory Bearman, Warren Grundfest

Proceedings Volume 3920, (2000) https://doi.org/10.1117/12.379599

KEYWORDS: Photons, Tissue optics, Backscatter, Tissues, Scattering, Natural surfaces, Absorption, Light scattering, Chromophores, 3D modeling

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Proceedings Article | 2 July 1999 Paper

Time-resolved laser-induced fluorescence of normal and atherosclerotic coronary artery

Laura Marcu, Jean-Michel Maarek, Michael Fishbein, Warren Grundfest

Proceedings Volume 3600, (1999) https://doi.org/10.1117/12.351029

KEYWORDS: Luminescence, Arteries, Tissues, Laser induced fluorescence, Oscilloscopes, Spectroscopy, Collagen, Fluorescence spectroscopy, Time resolved spectroscopy, Monochromators

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Proceedings Article | 2 July 1999 Paper

Classification of aortic atherosclerotic lesions with time-resolved fluorescence spectroscopy

Jean-Michel Maarek, Laura Marcu, Warren Grundfest, Michael Fishbein

Proceedings Volume 3600, (1999) https://doi.org/10.1117/12.351030

KEYWORDS: Luminescence, Time resolved spectroscopy, Statistical analysis, Pulsed laser operation, Fluorescence spectroscopy, Statistical modeling, Monochromators, Nitrogen lasers, Continuous wave operation

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Proceedings Article | 22 June 1999 Paper

Parameter optimization for excimer-based TMR clinical systems: an in-vivo study

Ramez Shehada, Thanassis Papaioannou, Warren Grundfest

Proceedings Volume 3590, (1999) https://doi.org/10.1117/12.350998

KEYWORDS: Excimer lasers, Laser ablation, Carbon dioxide lasers, In vivo imaging, Laser tissue interaction, Tissues, Laser drilling, Laser applications, Heart, Electromechanical design

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Proceedings Article | 6 May 1999 Paper

Effects of scattering in layered biological tissue on imaging spectroscopy data

Mark Arnoldussen, David Cohen, Gregory Bearman, Warren Grundfest

Proceedings Volume 3605, (1999) https://doi.org/10.1117/12.347570

KEYWORDS: Tissue optics, Reflectivity, Imaging spectroscopy, Scattering, Photon transport, Monte Carlo methods, Imaging systems, Tissues, Natural surfaces, Reflection

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Proceedings Article | 16 April 1998 Paper

Characterization of atherosclerotic lesions with laser-induced time-resolved fluorescence spectroscopy

Jean-Michel Maarek, Laura Marcu, Warren Grundfest

Proceedings Volume 3250, (1998) https://doi.org/10.1117/12.305377

KEYWORDS: Luminescence, Time resolved spectroscopy, Pulsed laser operation, Tissues, Collagen, Statistical analysis, Monochromators, Laser applications, Nitrogen lasers, Inspection

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Proceedings Article | 16 April 1998 Paper

Time-resolved laser-induced fluorescence of lipids involved in development of atherosclerotic lesion lipid-rich core

Laura Marcu, Jean-Michel Maarek, Warren Grundfest

Proceedings Volume 3250, (1998) https://doi.org/10.1117/12.305375

KEYWORDS: Luminescence, Laser induced fluorescence, Oscilloscopes, Monochromators, Photomultipliers, Pulsed laser operation, Nitrogen lasers, Sensors, Carbon monoxide, Fluorescence spectroscopy

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Proceedings Article | 7 May 1997 Paper

Time-resolved laser-induced fluorescence of arterial wall constituents: deconvolution algorithm and spectrotemporal characteristics

Jean-Michel Maarek, Wendy Snyder, Warren Grundfest

Proceedings Volume 2980, (1997) https://doi.org/10.1117/12.273512

KEYWORDS: Luminescence, Collagen, Deconvolution, Time resolved spectroscopy, Laser induced fluorescence, Tissue optics, Algorithm development, Tissues, Fluorescence spectroscopy, Absorption

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Proceedings Article | 17 May 1996 Paper

Factors affecting the outcome of excimer laser photorefractive keratectomy: a preliminary multivariable regression analysis

Ezra Maguen, Thanassis Papaioannou, Anthony Nesburn, James Salz, Cathy Warren, Warren Grundfest

Proceedings Volume 2673, (1996) https://doi.org/10.1117/12.240063

KEYWORDS: Excimer lasers, Eye models, Statistical analysis, Analytical research, Medical research, Laser applications, Refraction, Surgery, Ophthalmology, Laser vision correction

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Proceedings Article | 5 April 1996 Paper

Biologic fluorescence decay characteristics: determination by Laguerre expansion technique

Wendy Snyder, Jean-Michel Maarek, Thanassis Papaioannou, Vasilis Marmarelis, Warren Grundfest

Proceedings Volume 2679, (1996) https://doi.org/10.1117/12.237583

KEYWORDS: Luminescence, Pulsed laser operation, Collagen, Excimers, Deconvolution, Nitrogen, Excimer lasers, Monochromators, Statistical analysis, Oscilloscopes

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Proceedings Article | 2 April 1996 Paper

Photobleaching of native and exogenous (BPD-MA) fluorescence: an in-vivo tumor-bearing rat model

Thanassis Papaioannou, Sandor Vari, Vani Pergadia, Warren Grundfest, Jean-Michel Maarek

Proceedings Volume 2675, (1996) https://doi.org/10.1117/12.237531

KEYWORDS: Luminescence, Tumors, In vivo imaging, Lymphatic system, Photodynamic therapy, Tissue optics, Tissues, Oxygen, In vitro testing, Laser applications

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Proceedings Article | 9 February 1996 Paper

Telemedicine, health information networks, and computer-based patient records

Luis Kun, Yadin David, J. Fitzmaurice, Jeff Blair, Lewis Lorton, Warren Grundfest

Proceedings Volume 2618, (1996) https://doi.org/10.1117/12.231657

KEYWORDS: Medicine, Telemedicine, Standards development, Computing systems, Information technology, Surgery, Legal, X-rays, Medical research, Medical devices

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Proceedings Article | 27 October 1995 Paper

Effective use of the health care assets of the federal government

Warren Grundfest

Proceedings Volume 2499, (1995) https://doi.org/10.1117/12.225324

KEYWORDS: Medicine, Therapeutics, Standards development, Safety, Radiation effects, Intellectual property, Agriculture, Defense and security, Databases

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Proceedings Article | 12 April 1995 Paper

Near-infrared monitoring of hemoglobin content in the kidney during ischemia

Wendy Snyder, Jean-Michel Maarek, Sandor Vari, Laura Marcu, Thanassis Papaioannou, Vani Pergadia, Warren Grundfest

Proceedings Volume 2387, (1995) https://doi.org/10.1117/12.206827

KEYWORDS: Kidney, Ischemia, Blood, Near infrared spectroscopy, Blood circulation, Blood pressure, Semiconductor lasers, Surgery, Tissues, Photomultipliers

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Proceedings Article | 6 December 1994 Paper

Is there a conflict between improved health care delivery and lowering costs?

Warren Grundfest

Proceedings Volume 2307, (1994) https://doi.org/10.1117/12.195482

KEYWORDS: Medicine, Therapeutics, Surgery, Diagnostics and therapeutics, Manufacturing, Safety, Arteries, Laser therapeutics, Process control, Adaptive optics

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Proceedings Article | 19 May 1994 Paper

Near-infrared monitoring of perfusion and oxygen availability in abdominal organs and skeletal muscle during hypoxia

Jean-Michel Maarek, Sandor Vari, Laura Marcu, Thanassis Papaioannou, Vani Pergadia, Wendy Snyder, Warren Grundfest

Proceedings Volume 2135, (1994) https://doi.org/10.1117/12.175989

KEYWORDS: Kidney, Hypoxia, Liver, Blood, Tissues, Oxygen, Near infrared spectroscopy, Near infrared, Optical fibers, Spectroscopy

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Proceedings Article | 1 March 1994 Paper

Biodistribution detection of Photofrin porfimer sodium and benzoporphyrin derivative using a fiber optic sensor and ratio fluorometry

Sandor Vari, Theodore Papazoglou, Thanassis Papaioannou, Marigo Stavridi, Vani Pergadia, Michael Fishbein, Maurits van der Veen, Reem Thomas, Warren Grundfest

Proceedings Volume 2078, (1994) https://doi.org/10.1117/12.168656

KEYWORDS: Tissues, Luminescence, Tumors, Sodium, Laser induced fluorescence, Skin, Lymphatic system, Fluorescence spectroscopy, Liver, Spectroscopy

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