Prof. James W. Tunnell Profile

Prof. James W. Tunnell

Associate Professor/Biomedical Engineering at Univ of Texas at Austin

SPIE Involvement:

Conference Program Committee | Author | Student Chapter Advisor

Publications (38)

PROCEEDINGS ARTICLE | February 13, 2018

Raman spectroscopy reveals biophysical markers in skin cancer surgical margins

Proc. SPIE. 10490, Biomedical Vibrational Spectroscopy 2018: Advances in Research and Industry

KEYWORDS: Confocal microscopy, Tumors, Tissues, Skin, Skin cancer, Raman spectroscopy, Tissue optics, Mohs surgery

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PROCEEDINGS ARTICLE | February 16, 2017

Interpreting fiber structure from polarization dependent optical anisotropy

Proc. SPIE. 10068, Imaging, Manipulation, and Analysis of Biomolecules, Cells, and Tissues XV

KEYWORDS: Optical imaging, Data modeling, Polarization, Birefringence, Tissues, Spatial frequencies, Scattering, Particles, Light scattering, Structured optical fibers, Collagen, Scanning electron microscopy, Refraction, Mie scattering, Tissue optics, Anisotropy

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Polarized light is commonly used to detect optical anisotropies, such as birefringence, in tissues. This optical anisotropy is often attributed to underlying structural anisotropy in tissue, which may originate from regularly aligned collagen fibers. In these cases, the optical anisotropy, such as birefringence, is interpreted as a relative measure of the structural anisotropy of the collagen fibers. However, the relative amplitude of optical anisotropy depends on factors other than fiber orientation, and few models allow quantitative interpretation of absolute measures of true fiber orientation distribution from the optical signal. Our model uses the Mie solution to scattering of linearly polarized light from infinite cylindrical scatterers. The model is expanded to include populations of scatterers with physiologically relevant size and orientation distributions. We investigated the influences of fiber diameter, orientation distribution, and wavelength on the back-scattering signal with our computational model, and used these results to extract structural information from experimental fiber phantoms and bovine tendon. Our results demonstrated that by fitting our model to the experimental data using limited assumptions, we could extract fiber orientation distributions and diameters that were comparable to those found in scanning electron microscope images of the same fiber sample. We found a higher alignment of fibers in the bovine tendon sample, and the extracted fiber diameter was within the expected physiological range. Our model showed that the amplitude of optical anisotropy can vary widely due to factors other than the orientation distribution of fiber structures, including index of refraction, and therefore should not be taken as a sole indicator of structural anisotropy. This work highlights that the accuracy of model assumptions plays a crucial role in extracting quantitative structural information from optical anisotropy.

PROCEEDINGS ARTICLE | February 14, 2017

Tumor margin assessment in Mohs surgery using reflectance, fluorescence and Raman spectroscopy

Proc. SPIE. 10054, Advanced Biomedical and Clinical Diagnostic and Surgical Guidance Systems XV

KEYWORDS: Diffuse reflectance spectroscopy, Tumors, Tissues, Pathology, Skin, Luminescence, Fluorescence spectroscopy, Diagnostics, Collagen, Skin cancer, Raman spectroscopy, Biopsy, Mohs surgery

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PROCEEDINGS ARTICLE | February 9, 2017

Spectral biopsy for skin cancer diagnosis: initial clinical results

Proc. SPIE. 10037, Photonics in Dermatology and Plastic Surgery

KEYWORDS: Cancer, Diffuse reflectance spectroscopy, Data modeling, Fiber optics, Spectroscopy, Dermatology, Skin, Remote sensing, Luminescence, Fluorescence spectroscopy, Skin cancer, Raman spectroscopy, Melanoma, Biopsy, Data acquisition, Biomedical engineering, Clinical research

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PROCEEDINGS ARTICLE | February 6, 2017

Physiological basis for noninvasive skin cancer diagnosis using diffuse reflectance spectroscopy

Proc. SPIE. 10037, Photonics in Dermatology and Plastic Surgery

KEYWORDS: Principal component analysis, Tumor growth modeling, Cancer, Diffuse reflectance spectroscopy, Data modeling, Tissues, Scattering, Skin, Reflectivity, Skin cancer, Monte Carlo methods, Tissue optics

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SPIE Journal Paper | May 20, 2016

Color structured light imaging of skin

Yang, Bin , Lesicko, John , Moy, Austin , Reichenberg, Jason , Sacks, Michael , Tunnell, James

JBO Vol. 21 Issue 05

KEYWORDS: Structured light, Stereolithography, Skin, Reflectivity, Scattering, Tissues, Color imaging, Imaging systems, Spatial frequencies, Pathology

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PROCEEDINGS ARTICLE | April 27, 2016

Clinical skin imaging using color spatial frequency domain imaging (Conference Presentation)

Proc. SPIE. 9689, Photonic Therapeutics and Diagnostics XII

KEYWORDS: Optical properties, Tissues, Imaging systems, Spatial frequencies, Scattering, Dermatology, Skin, Diagnostics, Color imaging, Absorption

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PROCEEDINGS ARTICLE | April 26, 2016

Attenuation correction in molecular fluorescence imaging (Conference Presentation)

Proc. SPIE. 9696, Molecular-Guided Surgery: Molecules, Devices, and Applications II

KEYWORDS: Tumors, Tissues, Surgery, Scattering, Signal attenuation, Luminescence, Tissue optics, Optical calibration, In vitro testing, Absorption

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PROCEEDINGS ARTICLE | March 9, 2016

Polarized spatial frequency domain imaging of heart valve fiber structure

Proc. SPIE. 9710, Optical Elastography and Tissue Biomechanics III

KEYWORDS: Mueller matrices, Polarization, Birefringence, Tissues, Imaging systems, Light scattering, Heart, Polarizers, Tissue optics, Polarization analysis, Anisotropy

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PROCEEDINGS ARTICLE | March 7, 2016

Biophysical basis for noninvasive skin cancer detection using Raman spectroscopy

Proc. SPIE. 9704, Biomedical Vibrational Spectroscopy 2016: Advances in Research and Industry

KEYWORDS: Confocal microscopy, Optical fibers, Tumor growth modeling, Tissues, Spectroscopy, Skin, In situ metrology, Collagen, Skin cancer, Raman spectroscopy, Tissue optics

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PROCEEDINGS ARTICLE | February 29, 2016

Noninvasive skin cancer diagnosis using multimodal optical spectroscopy

Proc. SPIE. 9689, Photonic Therapeutics and Diagnostics XII

KEYWORDS: Optical design, Light sources, Cancer, Diffuse reflectance spectroscopy, Spectroscopy, Skin, Remote sensing, Luminescence, Spectrometers, Fluorescence spectroscopy, Skin cancer, Raman spectroscopy, Biopsy, Optical spectroscopy, Tissue optics

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SPIE Journal Paper | February 3, 2015

Impact of one-layer assumption on diffuse reflectance spectroscopy of skin

Hennessy, Ricky , Markey, Mia , Tunnell, James

JBO Vol. 20 Issue 02

KEYWORDS: Skin, Diffuse reflectance spectroscopy, Absorption, Tissue optics, Scattering, Magnesium, Refractive index, Reflectivity, Packaging, Tissues

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SPIE Journal Paper | November 6, 2014

Clinical study of noninvasive <italic<in vivo</italic< melanoma and nonmelanoma skin cancers using multimodal spectral diagnosis

Lim, Liang , Nichols, Brandon , Migden, Michael , Rajaram, Narasimhan , Reichenberg, Jason , Markey, Mia , Ross, Merrick , Tunnell, James

JBO Vol. 19 Issue 11

KEYWORDS: Skin, Melanoma, Laser induced fluorescence, Diagnostics, Raman spectroscopy, Remote sensing, Skin cancer, In vivo imaging, Tissues, Proteins

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SPIE Journal Paper | October 27, 2014

Effect of probe geometry and optical properties on the sampling depth for diffuse reflectance spectroscopy

Hennessy, Ricky , Goth, Will , Sharma, Manu , Markey, Mia , Tunnell, James

JBO Vol. 19 Issue 10

KEYWORDS: Optical properties, Scattering, Monte Carlo methods, Absorption, Anisotropy, Photons, Diffuse reflectance spectroscopy, Tissue optics, Reflectivity, Light scattering

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SPIE Journal Paper | September 24, 2014

Real-time absorption reduced surface fluorescence imaging

Yang, Bin , Tunnell, James

JBO Vol. 19 Issue 09

KEYWORDS: Luminescence, Absorption, Spatial frequencies, Tissues, Image processing, Video, Tumors, Image acquisition, Visualization, Natural surfaces

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SPIE Journal Paper | August 16, 2013

Attenuation-corrected fluorescence extraction for image-guided surgery in spatial frequency domain

Yang, Bin , Sharma, Manu , Tunnell, James

JBO Vol. 18 Issue 08

KEYWORDS: Luminescence, Tissues, Absorption, Tumors, Image-guided intervention, Scattering, Optical properties, Signal attenuation, Reflectivity, In vitro testing

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PROCEEDINGS ARTICLE | March 8, 2013

Attenuation corrected fluorescence extraction using spatial frequency domain imaging system

Proc. SPIE. 8618, Emerging Digital Micromirror Device Based Systems and Applications V

KEYWORDS: Tumors, Optical properties, Tissues, Imaging systems, Scattering, Signal attenuation, Luminescence, Reflectivity, Image-guided intervention, Absorption

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SPIE Journal Paper | March 1, 2013

Monte Carlo lookup table-based inverse model for extracting optical properties from tissue-simulating phantoms using diffuse reflectance spectroscopy

Hennessy, Ricky , Lim, Sam , Markey, Mia , Tunnell, James

JBO Vol. 18 Issue 03

KEYWORDS: Monte Carlo methods, Optical properties, Tissues, Diffuse reflectance spectroscopy, Tumor growth modeling, Photons, Absorption, Reflectivity, Data modeling, Scattering

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SPIE Journal Paper | April 20, 2012

Performance of a lookup table-based approach for measuring tissue optical properties with diffuse optical spectroscopy

Nichols, Brandon , Rajaram, Narasimhan , Tunnell, James

JBO Vol. 17 Issue 5

KEYWORDS: Scattering, Absorption, Reflectivity, Tissue optics, Optical properties, Tissues, Calibration, Oxygen, Mie scattering, Anisotropy

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SPIE Journal Paper | December 1, 2011

Development of a noncontact diffuse optical spectroscopy probe for measuring tissue optical properties

Bish, Sheldon , Rajaram, Narasimhan , Nichols, Brandon , Tunnell, James

JBO Vol. 16 Issue 12

KEYWORDS: Tissue optics, Scattering, Reflectivity, Optical properties, Polarization, Specular reflections, Tissues, Optical fibers, Absorption, Natural surfaces

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SPIE Journal Paper | July 1, 2011

Changes in morphology and optical properties of sclera and choroidal layers due to hyperosmotic agent

Zaman, Raiyan , Nichols, Brandon , Rylander, Henry , Wang, Tianyi , Tunnell, James , Welch, Ashley , Rajaram, Narasimhan

JBO Vol. 16 Issue 07

KEYWORDS: Sclera, Blood vessels, Optical properties, Blood, Absorption, Scattering, Eye, Tissue optics, Tissues, Phase modulation

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SPIE Journal Paper | January 1, 2011

Probe pressure effects on human skin diffuse reflectance and fluorescence spectroscopy measurements

Lim, Liang , Nichols, Brandon , Rajaram, Narasimhan , Tunnell, James

JBO Vol. 16 Issue 1

KEYWORDS: Skin, Absorption, Neck, Tissues, Diffuse reflectance spectroscopy, Scattering, Blood, Tissue optics, Luminescence, Collagen

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SPIE Journal Paper | May 1, 2010

Lookup-table method for imaging optical properties with structured illumination beyond the diffusion theory regime

Erickson, Tim , Mazhar, Amaan , Cuccia, David , Durkin, Anthony , Tunnell, James

JBO Vol. 15 Issue 03

KEYWORDS: Optical properties, Modulation, Reflectivity, Scattering, Absorption, Optical spheres, Photons, Diffusion, Tissue optics, Optical imaging

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SPIE Journal Paper | March 1, 2009

Near-infrared narrow-band imaging of gold/silica nanoshells in tumors

Puvanakrishnan, Priyaveena , Park, Jaesook , Diagaradjane, Parameshwaran , Schwartz, Jon , Coleman, Christopher , Gill-Sharp, Kelly , Sang, Kristina , Payne, J. Donald , Krishnan, Sunil , Tunnell, James

JBO Vol. 14 Issue 02

KEYWORDS: Tumors, Near infrared, Tissues, Composites, Absorption, Gold, Visualization, Tissue optics, Particles, Blood

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SPIE Journal Paper | March 1, 2009

Re-evaluation of model-based light-scattering spectroscopy for tissue spectroscopy

Lau, Condon , Scepanovic, Obrad , Mirkovic, Jelena , McGee, Sasha , Yu, Chung-Chieh , Fulghum, Stephen , Wallace, Michael , Tunnell, James , Bechtel, Kate , Feld, Michael

JBO Vol. 14 Issue 02

KEYWORDS: Light scattering, Reflectivity, Tissue optics, Scattering, Spectroscopy, Diffuse reflectance spectroscopy, Tissues, Packaging, Model-based design, Absorption

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PROCEEDINGS ARTICLE | February 28, 2009

In vivo determination of optical properties and fluorophore characteristics of non-melanoma skin cancer

Proc. SPIE. 7161, Photonic Therapeutics and Diagnostics V

KEYWORDS: Diffuse reflectance spectroscopy, Optical properties, Tissues, Scattering, Blood, Skin, Luminescence, Collagen, Laser induced fluorescence, Skin cancer

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Diffuse optical spectroscopy (DOS) and laser-induced fluorescence (LIF) techniques have widely been used as noninvasive tools for early cancer detection in several organs including the cervix, oral cavity and gastrointestinal tract. Using a combined DOS/LIF approach, one can simultaneously measure the morphology and biochemical composition of tissue and use these features to diagnose malignancy. We report for the first time to our knowledge both the optical properties and native fluorophore characteristics of non-melanoma skin cancer in the UV-visible range. We collected in vivo diffuse reflectance and intrinsic fluorescence measurements from 44 skin lesions on 37 patients. The skin sites were further categorized into three groups of non-melanoma skin cancer according to histopathology: 1) pre-cancerous actinic keratosis 2) malignant squamous cell carcinoma (SCC) and 3) basal cell carcinoma (BCC). We used a custom-built probe-based clinical system that collects both white light reflectance and laser-induced fluorescence in the wavelength range of 350-700 nm. We extracted the blood volume fraction, oxygen saturation, blood vessel size, tissue microarchitecture and melanin content from diffuse reflectance measurements. In addition, we determined the native fluorophore contributions of NADH, collagen and FAD from laser-induced fluorescence for all groups. The scattering from tissue decreased with progression from clinically normal to precancerous actinic keratosis to malignant SCC. A similar trend was observed for clinically normal skin and malignant BCC. Statistically significant differences were observed in the collagen contributions, which were lower in malignant SCC and BCC as compared to normal skin. Our data demonstrates that the mean optical properties and fluorophore contributions of normal, benign and malignant nonmelanoma cancers are significantly different from each other and can potentially be used as biomarkers for the early detection of skin cancer.

PROCEEDINGS ARTICLE | February 24, 2009

Narrow band imaging of tumors using gold nanoshells

Proc. SPIE. 7169, Advanced Biomedical and Clinical Diagnostic Systems VII

KEYWORDS: Gold, Near infrared, Tumors, Visualization, Tissues, Blood, Blood vessels, Composites, Tissue optics, Absorption

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PROCEEDINGS ARTICLE | February 18, 2009

Two-photon-induced photoluminescence imaging of gold nanoshell's tumor biodistribution

Proc. SPIE. 7192, Plasmonics in Biology and Medicine VI

KEYWORDS: Gold, Microscopes, Cancer, Tumors, Tissues, Particles, Luminescence, Multiplexing, Satellite navigation systems, Tissue optics

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PROCEEDINGS ARTICLE | February 12, 2009

Changes in morphology and optical properties of sclera due to hyperosmotic agent

Proc. SPIE. 7175, Optical Interactions with Tissue and Cells XX

KEYWORDS: Eye, Optical properties, Scattering, Blood, Blood vessels, Light scattering, Sclera, Oxygen, Eye models, Absorption

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The primary and the secondary goals of this study were to investigate the change in morphology and optical properties of sclera due to a hyperosmotic agent i.e. 100% anhydrous glycerol. We performed our experiments in vivo on the sclera of 8 rabbits and 3 miniature pigs. All the animals were under anesthetic for the entire experiment according to an approved protocol. The position of the eye was stabilized with a suture placed in the limbus. Glycerol was delivered to sclera in 2 methods (i) injection (using a hypodermic needle 27G ½), (ii) direct application after 0.3 cm incision at conjunctiva. A camera attached to a slit lamp was used to capture the morphological changes of the sclera. For the secondary goal we used a diffuse optical spectroscopy (DOS) system with a linear fiber arrangement to measure reflectance from the sclera before and after application of glycerol. The probe source-detector separation was set to 370 μm for optimal penetration depth. We fit the measured diffuse reflectance to a Lookup Table (LUT)-based inverse model specific to our probe geometry to determine the scattering and absorption properties of the sclera. This method estimated the size and density of scatterers, absorbers-blood volume fraction, melanin concentration, oxygen saturation, and blood vessel size. The results illustrated that the initial clearing of sclera started 3 minutes after injecting glycerol to sclera. The sclera became completely transparent at 8 minutes and stayed clear for 10-15 minutes. During this time the choroid layer was visible through sclera. The clear sclera became less transparent over next 11 minutes and became completely opaque once we applied 0.9% saline to hydrate the sclera. These dehydration and hydration cycles were repeated 4 times for each eye and the results were consistent for all animal models. When glycerol was applied directly to sclera after the incision at the conjunctiva, the sclera became transparent instantaneously. For the secondary goal, the changes in optical properties of sclera were monitored during the dehydration and hydration cycles. The reduced scattering coefficient decreased when glycerol was injected and it further reduced with direct application. The scattering increased after re-hydration. We also measured the blood volume fraction, melanin concentration, oxygen saturation, and blood vessels diameter to calculate absorption coefficient with the DOS system. This study provided a novel way to identify morphological changes of sclera in addition to measuring changes in optical properties due to hyper osmotic agent. The changes in optical properties were consistent with the morphological changes in sclera during the dehydration and hydration cycles.

SPIE Journal Paper | September 1, 2008

Lookup table–based inverse model for determining optical properties of turbid media

Rajaram, Narasimhan , Nguyen, Tri , Tunnell, James

JBO Vol. 13 Issue 05

KEYWORDS: Tissue optics, Tissues, Tumor growth modeling, Optical properties, Diffuse reflectance spectroscopy, Absorption, Data modeling, Scattering, Reflectivity, Calibration

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PROCEEDINGS ARTICLE | February 25, 2008

Clinical instrument for spectral diagnosis of cutaneous malignancy

Proc. SPIE. 6848, Advanced Biomedical and Clinical Diagnostic Systems VI

KEYWORDS: Diffuse reflectance spectroscopy, Tissues, Scattering, Skin, Luminescence, Light scattering, Reflectivity, Melanoma, Tissue optics, Absorption

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PROCEEDINGS ARTICLE | February 22, 2008

Gold nanoshell mediated hyperthermia enhances the efficacy of radiation therapy

Proc. SPIE. 6865, Nanoscale Imaging, Sensing, and Actuation for Biomedical Applications V

KEYWORDS: Gold, Thermography, Tumors, Tissues, Magnetic resonance imaging, Magnetism, Radiotherapy, Laser irradiation, Thermometry, Temperature metrology

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PROCEEDINGS ARTICLE | February 21, 2008

3D microscopy of gold nanoshells in tumors using two-photon-induced photoluminescence

Proc. SPIE. 6869, Plasmonics in Biology and Medicine V

KEYWORDS: Gold, Near infrared, 3D acquisition, Cancer, Tumors, Silica, Microscopy, Particles, Luminescence, 3D image processing

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PROCEEDINGS ARTICLE | September 12, 2003

Thermal response of human skin epidermis in different skin types to 595-nm laser irradiation and cryogen spray cooling: an ex-vivo study

Proc. SPIE. 4949, Lasers in Surgery: Advanced Characterization, Therapeutics, and Systems XIII

KEYWORDS: Injuries, Laser therapeutics, Laser coagulation, Blood vessels, Skin, Dye lasers, Laser irradiation, In vivo imaging, Pulsed laser operation, Cryogenics

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PROCEEDINGS ARTICLE | June 17, 2002

Cryogen spray cooling: effects of cryogen film on heat removal and light transmission

Proc. SPIE. 4609, Lasers in Surgery: Advanced Characterization, Therapeutics, and Systems XII

KEYWORDS: Laser therapeutics, Laser vision correction, Signal attenuation, Glasses, Skin, Pulsed laser operation, Cryogenics, In vitro testing, Temperature metrology, Laser systems engineering

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PROCEEDINGS ARTICLE | June 17, 2002

In-vivo study of epidermal protection by cryogen spray cooling during pulsed-laser irradiation at high radiant exposures

Proc. SPIE. 4609, Lasers in Surgery: Advanced Characterization, Therapeutics, and Systems XII

KEYWORDS: Injuries, Laser therapeutics, Tissues, Blood, Blood vessels, Skin, Laser damage threshold, In vivo imaging, Pulsed laser operation, Cryogenics

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