Dr. Gracie Vargas Profile

Dr. Gracie Vargas

Professor

SPIE Involvement:

Conference Chair | Editor | Author

Publications (32)

Proceedings Article | 13 March 2024 Presentation

Widefield multispectral imaging to evaluate spectral biomarkers associated with oral epithelial dysplasia and squamous cell carcinoma in a hamster buccal model and human clinical samples

Paula Villarreal, Suimin Qiu, Orly Coblens, Tyler Peterson, Bofan Song, Xingde Li, Rongguang Liang, Gracie Vargas

Proceedings Volume PC12818, (2024) https://doi.org/10.1117/12.3003202

KEYWORDS: Multispectral imaging, Tumor growth modeling, Statistical modeling, Cancer detection, Tissues, Autofluorescence, Tunable filters, Neck, Liquid crystals, Light emitting diodes

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Proceedings Article | 13 March 2024 Presentation

Benchtop to handheld: characterization and optimization of a ring illuminator/detector in a handheld endogenous fluorescence imaging probe

Paula Villarreal, Tyler Peterson, Bofan Song, Rongguang Liang, Gracie Vargas

Proceedings Volume PC12833, PC1283304 (2024) https://doi.org/10.1117/12.3009704

KEYWORDS: Fluorescence, Light sources and illumination, Imaging systems, Autofluorescence imaging, Signal detection, Light emitting diodes, LED lighting, Fluorescence imaging, Diseases and disorders, Ultraviolet light emitting diodes

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Proceedings Article | 6 March 2023 Presentation

Design and characterization of handheld multiphoton probe for intraoral imaging

Tyler Peterson, Hongzhang Ma, Paula Villarreal, Xingde Li, Gracie Vargas, Rongguang Liang

Proceedings Volume PC12370, PC1237007 (2023) https://doi.org/10.1117/12.2657635

KEYWORDS: Image resolution, Image quality, Tissues, Prisms, Natural surfaces, Multiphoton fluorescence microscopy, Manufacturing, Design for manufacturability, Cancer, Cameras

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Proceedings Article | 6 March 2023 Presentation

Analysis considerations for multimodal based approaches in diagnostics

Paula Villarreal, Suimin Qiu, Xingde Li, Rongguang Liang, Gracie Vargas

Proceedings Volume PC12370, PC1237008 (2023) https://doi.org/10.1117/12.2657771

KEYWORDS: Diagnostics, Optical imaging, Multiphoton microscopy, Multimodal imaging, Luminescence, Tumor growth modeling, Tissues, Optical sensing, Cancer

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Proceedings Article | 5 March 2021 Presentation

Designing a multimodal imaging workflow for large area fluorescence with nonlinear optical microscopy for oral neoplasia detection: preclinical model and clinical sample study

Rahul Pal, Paula Villarreal, Xiaoying Yu, Suimin Qiu, Orly Coblens, Gracie Vargas

Proceedings Volume 11622, 116220I (2021) https://doi.org/10.1117/12.2591286

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Proceedings Article | 5 March 2021 Presentation

A review of recent reports on the applications of optical technologies to detect SARS-CoV-2

Gracie Vargas

Proceedings Volume 11633, 1163305 (2021) https://doi.org/10.1117/12.2590983

KEYWORDS: Viruses, Sensors, Sensor technology, Polymers, Optical sensors, Image sensors

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Proceedings Article | 5 March 2021 Presentation

Use of preclinical models alongside clinical tissues to develop a noninvasive multimodal fluorescence detection approach for oral neoplasia detection

Paula Villarreal, Rahul Pal, Xiaoying Yu, Orly Coblens, Suimin Qiu, Rongguang Liang, Xingde Li, Gracie Vargas

Proceedings Volume 11633, 116330I (2021) https://doi.org/10.1117/12.2591126

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SPIE Journal Paper | 16 November 2020 Open Access

Multimodal widefield fluorescence imaging with nonlinear optical microscopy workflow for noninvasive oral epithelial neoplasia detection: a preclinical study

Rahul Pal, Paula Villarreal, Xiaoying Yu, Suimin Qiu, Gracie Vargas

JBO, Vol. 25, Issue 11, 116008, (November 2020) https://doi.org/10.1117/12.10.1117/1.JBO.25.11.116008

KEYWORDS: Inflammation, Roentgenium, Luminescence, In vivo imaging, Multimodal imaging, Microscopy, Tissues, Optical microscopy, Optical imaging, Tumors

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Significance: Early detection of epithelial cancers and precancers/neoplasia in the presence of benign lesions is challenging due to the lack of robust in vivo imaging and biopsy guidance techniques. Label-free nonlinear optical microscopy (NLOM) has shown promise for optical biopsy through the detection of cellular and extracellular signatures of neoplasia. Although in vivo microscopy techniques continue to be developed, the surface area imaged in microscopy is limited by the field of view. FDA-approved widefield fluorescence (WF) imaging systems that capture autofluorescence signatures of neoplasia provide molecular information at large fields of view, which may complement the cytologic and architectural information provided by NLOM. Aim: A multimodal imaging approach with high-sensitivity WF and high-resolution NLOM was investigated to identify and distinguish image-based features of neoplasia from normal and benign lesions. Approach:In vivo label-free WF imaging and NLOM was performed in preclinical hamster models of oral neoplasia and inflammation. Analyses of WF imaging, NLOM imaging, and dual modality (WF combined with NLOM) were performed. Results: WF imaging showed increased red-to-green autofluorescence ratio in neoplasia compared to inflammation and normal oral mucosa (p < 0.01). In vivo assessment of the mucosal tissue with NLOM revealed subsurface cytologic (nuclear pleomorphism) and architectural (remodeling of extracellular matrix) atypia in histologically confirmed neoplastic tissue, which were not observed in inflammation or normal mucosa. Univariate and multivariate statistical analysis of macroscopic and microscopic image-based features indicated improved performance (94% sensitivity and 97% specificity) of a multiscale approach over WF alone, even in the presence of benign lesions (inflammation), a common confounding factor in diagnostics. Conclusions: A multimodal imaging approach integrating strengths from WF and NLOM may be beneficial in identifying oral neoplasia. Our study could guide future studies on human oral neoplasia to further evaluate merits and limitations of multimodal workflows and inform the development of multiscale clinical imaging systems.

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Proceedings Article | 3 May 2016 Presentation

Combining large area fluorescence with multiphoton microscopy for improved detection of oral epithelial neoplasia (Conference Presentation)

Rahul Pal, Jinping Yang, Suimin Qiu, Susan McCammon, Vicente Resto, Gracie Vargas

Proceedings Volume 9701, 970109 (2016) https://doi.org/10.1117/12.2213927

KEYWORDS: Luminescence, Multiphoton microscopy, Microscopy, 3D modeling, Multiphoton fluorescence microscopy, Harmonic generation, Target detection, Analog electronics, Glucose, Connective tissue

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Proceedings Article | 27 April 2016 Presentation

Volumetric imaging of oral epithelial neoplasia by MPM-SHGM: epithelial connective tissue interface (Conference Presentation)

Rahul Pal, Jinping Yang, Suimin Qiu, Vicente Resto, Susan McCammon, Gracie Vargas

Proceedings Volume 9712, 971216 (2016) https://doi.org/10.1117/12.2213942

KEYWORDS: Interfaces, Connective tissue, 3D modeling, Multiphoton microscopy, Microscopy, Diagnostics, Tumor growth modeling, Second-harmonic generation, Image analysis, Cancer

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SPIE Journal Paper | 15 April 2013 Open Access

Optical coherence tomography for assessment of microbicide safety in a small animal model

Brent Bell, Kathleen Vincent, Nigel Bourne, Gracie Vargas, Massoud Motamedi

JBO, Vol. 18, Issue 04, 046010, (April 2013) https://doi.org/10.1117/12.10.1117/1.JBO.18.4.046010

KEYWORDS: Optical coherence tomography, Tissues, Animal model studies, In vivo imaging, Safety, Imaging systems, Tissue optics, Photomicroscopy, Toxicity, Visualization

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Proceedings Article | 22 March 2013 Paper

Combination of widefield fluorescence imaging and nonlinear optical microscopy of oral epithelial neoplasia

Rahul Pal, Kert Edward, Tyra Brown, Liang Ma, Jinping Yang, Susan McCammon, Massoud Motamedi, Gracie Vargas

Proceedings Volume 8572, 85720M (2013) https://doi.org/10.1117/12.2005144

KEYWORDS: Luminescence, Microscopy, Tissues, Multiphoton microscopy, Cancer, Atrial fibrillation, Optical imaging, Harmonic generation, Tumors, Biopsy

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Proceedings Article | 22 February 2013 Paper

Nonlinear optical microscopy and microspectroscopy of oral precancers and early cancer

Gracie Vargas, Kert Edward

Proceedings Volume 8588, 85881U (2013) https://doi.org/10.1117/12.2005239

KEYWORDS: Imaging spectroscopy, Spectroscopy, Microscopy, Cancer, Multiphoton microscopy, Optical microscopy, Multiphoton spectroscopy, Animal model studies, Tumor growth modeling, Luminescence

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SPIE Journal Paper | 1 November 2012 Open Access

Automated segmentation algorithm for detection of changes in vaginal epithelial morphology using optical coherence tomography

Shahab Chitchian, Kathleen Vincent, Gracie Vargas, Massoud Motamedi

JBO, Vol. 17, Issue 11, 116004, (November 2012) https://doi.org/10.1117/12.10.1117/1.JBO.17.11.116004

KEYWORDS: Image segmentation, Optical coherence tomography, Tissues, Algorithm development, Image filtering, Detection and tracking algorithms, Toxicity, Image processing algorithms and systems, Natural surfaces, Biopsy

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Proceedings Article | 9 February 2012 Paper

NF-kB activation as a biomarker of light injury using a transgenic mouse model

Ginger Pocock, Adam Boretsky, Heuy-Ching Wang, Dallas Golden, Praveena Gupta, Gracie Vargas, Jeffrey Oliver, Massoud Motamedi

Proceedings Volume 8221, 822108 (2012) https://doi.org/10.1117/12.908835

KEYWORDS: Retina, Luminescence, Injuries, Brain, Microscopy, Neuroimaging, Mouse models, In vivo imaging, Confocal microscopy, Laser induced damage

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Proceedings Article | 28 February 2011 Paper

Two-photon autofluorescence spectroscopy of oral mucosa tissue

Kert Edward, Tuya Shilagard, Suimin Qiu, Gracie Vargas

Proceedings Volume 7903, 79031Q (2011) https://doi.org/10.1117/12.875049

KEYWORDS: Spectroscopy, Imaging spectroscopy, Cancer, Multiphoton spectroscopy, Signal detection, Second-harmonic generation, Tissue optics, Biopsy, Tissues, Mirrors

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Proceedings Article | 17 February 2010 Paper

Feasibility of using gold nanorods for optical contrast in two photon microscopy of oral carcinogenesis

Saam Motamedi, Tuya Shilagard, Luke Koong, Gracie Vargas

Proceedings Volume 7576, 75760Z (2010) https://doi.org/10.1117/12.843036

KEYWORDS: Tissues, Signal detection, In vivo imaging, Cancer, Gold, Luminescence, Two photon excitation microscopy, Tumor growth modeling, Confocal microscopy, Nanorods

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SPIE Journal Paper | 1 March 2008 Open Access

Use of hyperosmotic chemical agent to improve the laser treatment of cutaneous vascular lesions

Gracie Vargas, Jennifer Barton, Ashley Welch

JBO, Vol. 13, Issue 02, 021114, (March 2008) https://doi.org/10.1117/12.10.1117/1.2907327

KEYWORDS: Skin, Blood vessels, Laser coagulation, Tissue optics, Doppler effect, Laser irradiation, Tissues, Blood circulation, Laser therapeutics, Signal attenuation

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Proceedings Article | 23 March 2007 Paper

Quantitative intracellular calcium sensing with two-photon fluorescence lifetime imaging microscopy

Eddy Kuwana, Gracie Vargas-Adams, Todd Pappas, Anton Liopo, Massoud Motamedi

Proceedings Volume 6424, 64242L (2007) https://doi.org/10.1117/12.723959

KEYWORDS: Calcium, Brain, Luminescence, Tissues, Fluorescence lifetime imaging, Microscopy, Neuroimaging, Calibration, Signal processing, Neurons

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Proceedings Article | 10 February 2007 Paper

In vivo mucosal tissue imaging using fiber-based two-photon approach

Xudong Xiao, Tuya Shilagard, Gracie Vargas

Proceedings Volume 6442, 644220 (2007) https://doi.org/10.1117/12.708017

KEYWORDS: Collagen, Multiphoton microscopy, In vivo imaging, Single mode fibers, Photonic crystal fibers, Luminescence, Microscopy, Tissues, Photonic crystals, Two photon imaging

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Proceedings Article | 22 February 2006 Paper

In vivo multiphoton and second harmonic generation microscopy of epithelial carcinogenesis

Gracie Vargas, Tuya Shilagard, Ju Sun, Massoud Motamedi

Proceedings Volume 6091, 60910B (2006) https://doi.org/10.1117/12.646564

KEYWORDS: In vivo imaging, Biopsy, Multiphoton microscopy, Tissues, Second-harmonic generation, Photomicroscopy, Microscopy, Harmonic generation, Collagen, Tumor growth modeling

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Proceedings Article | 1 July 2004 Paper

Creating the invisible man

A. Welch, Chris Humphrey, Gracie Vargas, Oliver Stumpp, Chris Rylander

Proceedings Volume 5319, (2004) https://doi.org/10.1117/12.537256

KEYWORDS: Skin, Blood vessels, In vivo imaging, Tissues, Blood circulation, Tissue optics, Refractive index, In vitro testing, Collimation, Light scattering

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SPIE Journal Paper | 1 March 2004 Open Access

Use of optical coherence tomography to monitor biological tissue freezing during cryosurgery

Bernard Choi, Thomas Milner, Jeehyun Kim, Jared Goodman, Gracie Vargas, Guillermo Aguilar, John Nelson

JBO, Vol. 9, Issue 02, (March 2004) https://doi.org/10.1117/12.10.1117/1.1648647

KEYWORDS: Optical coherence tomography, Skin, Liquids, Tissue optics, Nitrogen, Water, In vivo imaging, Reflectivity, Tissues, Scattering

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Proceedings Article | 1 August 2003 Paper

In vivo results using photothermal tomography for imaging cutaneous blood vessels

Bernard Choi, Boris Majaron, Gracie Vargas, Byungjo Jung, Oliver Stumpp, Nicole Kang, Kristen Kelly, Ashley Welch, J. Stuart Nelson

Proceedings Volume 5047, (2003) https://doi.org/10.1117/12.484140

KEYWORDS: Skin, Blood vessels, Infrared imaging, Infrared radiation, Laser irradiation, Infrared cameras, Absorption, In vivo imaging, Tomography, Laser therapeutics

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Proceedings Article | 17 June 2002 Paper

Dynamic measurements of laser light attenuation by cryogen film and frost formation

Bernard Choi, Guillermo Aguilar, Gracie Vargas, Ashley Welch, J. Stuart Nelson

Proceedings Volume 4609, (2002) https://doi.org/10.1117/12.432051

KEYWORDS: Cryogenics, Transmittance, Skin, Glasses, Light scattering, Pulsed laser operation, Optical testing, Sensors, Signal attenuation, Liquids

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Proceedings Article | 9 July 2001 Paper

Thermally induced birefringence changes in cartilage using polarization-sensitive optical coherence tomography

Jong-In Youn, Gracie Vargas, Mathieu Ducros, Sergey Telenkov, Brian Wong, Thomas Milner

Proceedings Volume 4257, (2001) https://doi.org/10.1117/12.434742

KEYWORDS: Cartilage, Laser irradiation, Birefringence, Polarization, Optical coherence tomography, Infrared imaging, Collagen, Nd:YAG lasers, Radiometry, Thermodynamics

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Proceedings Article | 13 June 2000 Paper

In-vitro Erbium:YAG laser lithotripsy

Kin Foong Chan, Gracie Vargas, Patricia Parker, Joel Teichman, Randolph Glickman, H. Stan McGuff, Ashley Welch

Proceedings Volume 3914, (2000) https://doi.org/10.1117/12.388046

KEYWORDS: Er:YAG lasers, Calculus, Acoustics, Sapphire, Laser lithotripsy, Plasma, Fiber lasers, Pulsed laser operation, Laser therapeutics, Laser energy

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Proceedings Article | 17 May 2000 Paper

Selective photocoagulation of cutaneous blood vessels: evaluation of vessel damage by color Doppler optical coherence tomography

Gracie Vargas, Mathieu Ducros, Susan Dozier, Jennifer Barton, Ashley Welch

Proceedings Volume 3907, (2000) https://doi.org/10.1117/12.386245

KEYWORDS: Blood vessels, Doppler tomography, Blood, Blood circulation, Visualization, Imaging systems, Video, Doppler effect, Optical coherence tomography, Skin

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Proceedings Article | 17 May 2000 Paper

Use of osmotically active agents to alter optical properties of tissue: influence on the detected fluorescence signal from a subsurface target

Gracie Vargas, Kin Foong Chan, Sharon Thomsen, Ashley Welch

Proceedings Volume 3907, (2000) https://doi.org/10.1117/12.386242

KEYWORDS: Signal detection, Tissue optics, Skin, Luminescence, Scattering, Tissues, In vitro testing, In vivo imaging, Optical properties, Fluorescence spectroscopy

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Proceedings Article | 28 April 2000 Paper

Influence of optical absorption on urinary calculus threshold fluence and ablation efficiency during infrared laser ablation

Kin Foong Chan, Daniel Hammer, Bernard Choi, Gracie Vargas, Brian Sorg, T. Joshua Pfefer, Joel Teichman, H. Stan McGuff, Hans Pratisto, E. Duco Jansen, Ashley Welch

Proceedings Volume 3925, (2000) https://doi.org/10.1117/12.384253

KEYWORDS: Laser ablation, Absorption, Calculi, Laser damage threshold, Tissue optics, Calculus, Absorbance, Hard tissue optics, Free electron lasers, Infrared radiation

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Proceedings Article | 22 June 1999 Paper

Mechanisms of laser-induced thermal coagulation of whole blood in vitro

T. Joshua Pfefer, Bernard Choi, Gracie Vargas, Karen McNally-Heintzelman, Ashley Welch

Proceedings Volume 3590, (1999) https://doi.org/10.1117/12.350970

KEYWORDS: Blood, Pulsed laser operation, Temperature metrology, Laser damage threshold, Optical coherence tomography, Scattering, In vitro testing, Laser scattering, Cameras, Skin

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Proceedings Article | 30 April 1999 Paper

Assessing vessel damage with color Doppler optical coherence tomography following irradiations with cooling

Gracie Vargas, Jennifer Barton, Bernard Choi, Joseph Izatt, Ashley Welch

Proceedings Volume 3598, (1999) https://doi.org/10.1117/12.347488

KEYWORDS: Skin, Blood vessels, Cryogenics, Temperature metrology, Laser irradiation, Optical coherence tomography, Ferroelectric materials, Doppler tomography, Blood circulation, Pulsed laser operation

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