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Bioimaging and Biomedical Optics Commons™

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Medicine and Health Sciences

2013

Articles 1 - 10 of 10

Full-Text Articles in Bioimaging and Biomedical Optics

Dopaminergic Modulation Of Memory And Affective Processing In Parkinson Depression, Lee X. Blonder, John T. Slevin, Richard J. Kryscio, Catherine A. Martin, Anders H. Andersen, Charles D Smith, Frederick A. Schmitt Nov 2013

Dopaminergic Modulation Of Memory And Affective Processing In Parkinson Depression, Lee X. Blonder, John T. Slevin, Richard J. Kryscio, Catherine A. Martin, Anders H. Andersen, Charles D Smith, Frederick A. Schmitt

Magnetic Resonance Imaging and Spectroscopy Center Faculty Publications

Depression is common in Parkinson's disease and is associated with cognitive impairment. Dopaminergic medications are effective in treating the motor symptoms of Parkinson's disease; however, little is known regarding the effects of dopaminergic pharmacotherapy on cognitive function in depressed Parkinson patients. This study examines the neuropsychological effects of dopaminergic pharmacotherapy in Parkinsonian depression. We compared cognitive function in depressed and non-depressed Parkinson patients at two time-points: following overnight withdrawal and after the usual morning regimen of dopaminergic medications. A total of 28 non-demented, right-handed patients with mild to moderate idiopathic Parkinson's disease participated. Ten of these patients were depressed according …

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Spectral Discrimination Of Breast Pathologies In Situ Using Spatial Frequency Domain Imaging, Ashley M. Laughney, Venkataramanan Krishnaswamy, Elizabeth J. Rizzo, Mary C. Schwab, Richard J. Barth, David J. Cuccia, Bruce J. Tromberg, Keith D. Paulsen, Brian W. Pogue, Wendy A. Wells Aug 2013

Spectral Discrimination Of Breast Pathologies In Situ Using Spatial Frequency Domain Imaging, Ashley M. Laughney, Venkataramanan Krishnaswamy, Elizabeth J. Rizzo, Mary C. Schwab, Richard J. Barth, David J. Cuccia, Bruce J. Tromberg, Keith D. Paulsen, Brian W. Pogue, Wendy A. Wells

Dartmouth Scholarship

Introduction: Nationally, 25% to 50% of patients undergoing lumpectomy for local management of breast cancer require a secondary excision because of the persistence of residual tumor. Intraoperative assessment of specimen margins by frozen-section analysis is not widely adopted in breast-conserving surgery. Here, a new approach to wide-field optical imaging of breast pathology in situ was tested to determine whether the system could accurately discriminate cancer from benign tissues before routine pathological processing.

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Fluorescence Characterization Of Quantum Dots For Use As Biomarkers, Logan M. Grimes Jun 2013

Fluorescence Characterization Of Quantum Dots For Use As Biomarkers, Logan M. Grimes

Materials Engineering

Fluorescence profiles of quantum dots (QDs) were characterized to select the ideal QDs for encapsulation in phospholipids for use as biomarkers to selectively adhere to cancer cells. QDs were synthesized and extracted 0, 30, 60, and 90 seconds after precursor compounds were mixed. These extractions were isolated by extraction time. Portions from each vial were coated in a zinc sulfide shelling procedure, leaving at least half of the QD solution unshelled. These samples were characterized over four days to monitor fluctuations in fluorescence. This was done utilizing an Ocean Optics spectrometer in conjunction with Spectra Suite software. The central wavelength, …

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Dynamic Dual-Tracer Mri-Guided Fluorescence Tomography To Quantify Receptor Density In Vivo, Scott C. Davis, Kimberley S. Samkoe, Kenneth M. Tichauer, Kristian J. Sexton, Jason R. Gunn, Sophie J. Deharvengt, Tayyaba Hasan, Brian W. Pogue May 2013

Dynamic Dual-Tracer Mri-Guided Fluorescence Tomography To Quantify Receptor Density In Vivo, Scott C. Davis, Kimberley S. Samkoe, Kenneth M. Tichauer, Kristian J. Sexton, Jason R. Gunn, Sophie J. Deharvengt, Tayyaba Hasan, Brian W. Pogue

Dartmouth Scholarship

The up-regulation of cell surface receptors has become a central focus in personalized cancer treatment; however, because of the complex nature of contrast agent pharmacokinetics in tumor tissue, methods to quantify receptor binding in vivo remain elusive. Here, we present a dual-tracer optical technique for noninvasive estimation of specific receptor binding in cancer. A multispectral MRI-coupled fluorescence molecular tomography system was used to image the uptake kinetics of two fluorescent tracers injected simultaneously, one tracer targeted to the receptor of interest and the other tracer a nontargeted reference. These dynamic tracer data were then fit to a dual-tracer compartmental model …

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Biomedical Photoacoustic Imaging Using Gas-Coupled Laser Acoustic Detection, Jami Johnson May 2013

Biomedical Photoacoustic Imaging Using Gas-Coupled Laser Acoustic Detection, Jami Johnson

Student Research Initiative

Several detection methods have been explored for photoacoustic and ultrasound imaging of biological tissues. Piezoelectric transducers are commonly used, which require contact with the sample to be imaged and have limiting bandwidth characteristics. Interferometry detection exhibits improved bandwidth characteristics and resolution, yet generally require complicated optics and the incorporation of a contacting reflective medium. In this paper, we report the use of a noncontact photoacoustic imaging system that does not require the use of a reflective layer. A simple, robust technique known as gas-coupled laser acoustic detection is used, which has previously been applied to evaluation of composite materials. This …

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Delayed Thrombus Resolution And Fibroproliferative Vascular Wound Healing From Deficiency Of Type Iii Collagen: A Paradoxical Mechanism For Tissue Fragility, Amy J. Reid May 2013

Delayed Thrombus Resolution And Fibroproliferative Vascular Wound Healing From Deficiency Of Type Iii Collagen: A Paradoxical Mechanism For Tissue Fragility, Amy J. Reid

Dissertations & Theses (Open Access)

Vascular Ehlers-Danlos syndrome is a heritable disease of connective tissue caused by mutations in COL3A1, conferring a tissue deficiency of type III collagen. Cutaneous wounds heal poorly in these patients, and they are susceptible to spontaneous and catastrophic rupture of expansible hollow organs like the gut, uterus, and medium-sized to large arteries, which leads to premature death. Although the predisposition for organ rupture is often attributed to inherent tissue fragility, investigation of arteries from a haploinsufficient Col3a1 mouse model (Col3a1+/-) demonstrates that mutant arteries withstand even supraphysiologic pressures comparably to wild-type vessels. We hypothesize that injury …

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Scanning In Situ Spectroscopy Pplatform For Imaging Surgical Breast Tissue Specimens, Venkataramanan Krishnaswamy, Ashley M. Laughney, Wendy A. Wells, Keith D. Paulsen, Brian W. Pogue Jan 2013

Scanning In Situ Spectroscopy Pplatform For Imaging Surgical Breast Tissue Specimens, Venkataramanan Krishnaswamy, Ashley M. Laughney, Wendy A. Wells, Keith D. Paulsen, Brian W. Pogue

Dartmouth Scholarship

A non-contact localized spectroscopic imaging platform has been developed and optimized to scan 1 x 1 cm² square regions of surgically resected breast tissue specimens with ~150-micron resolution. A color corrected, image-space telecentric scanning design maintained a consistent sampling geometry and uniform spot size across the entire imaging field. Theoretical modeling in ZEMAX allowed estimation of the spot size, which is equal at both the center and extreme positions of the field with ~5% variation across the designed waveband, indicating excellent color correction. The spot sizes at the center and an extreme field position were also measured experimentally using the …

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Automated Point-Of-Care Image Processing Methodology For The Diagnosis Of Malaria, Michael B. Jorgensen Jan 2013

Automated Point-Of-Care Image Processing Methodology For The Diagnosis Of Malaria, Michael B. Jorgensen

Master's Theses

Malaria has profoundly influenced human history for over four thousand years and despite numerous attempts at eradication, the prevention, diagnosis, and treatment of malaria have been largely ineffective. More than five hundred million people are affected by malaria every year resulting in over one million deaths. Drug resistance development by the parasite has diminished the effectiveness of numerous treatment options due, in part, to overtreatment of negative patients based on insufficient clinical algorithms and diagnostic methods. The goal of this research was to develop an image analysis algorithm to diagnose malaria with a high degree of sensitivity and specificity in …

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The Role Of Tissue Sound Speed As A Surrogate Marker Of Breast Density, Mark Sak Jan 2013

The Role Of Tissue Sound Speed As A Surrogate Marker Of Breast Density, Mark Sak

Wayne State University Dissertations

Breast density is one of the strongest predictors of breast cancer risk as women with the densest breasts have a three- to five-fold increase in risk compared to women with the least dense breasts. Breast density is currently measured by using mammography, the current gold standard for breast imaging. There are many shortcomings to using mammography to measure breast density, including the use of ionizing radiation. Ultrasound tomography (UST) does not use ionizing radiation and can create tomographic breast sound speed images. These sound speed images are useful because breast density is proportional to sound speed. The purpose of this …

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Noninvasive Near-Infrared Diffuse Optical Monitoring Of Cerebral Hemodynamics And Autoregulation, Ran Cheng Jan 2013

Noninvasive Near-Infrared Diffuse Optical Monitoring Of Cerebral Hemodynamics And Autoregulation, Ran Cheng

Theses and Dissertations--Biomedical Engineering

Many cerebral diseases are associated with abnormal cerebral hemodynamics and impaired cerebral autoregulation (CA). CA is a mechanism to maintain cerebral blood flow (CBF) stable when mean arterial pressure (MAP) fluctuates. Evaluating these abnormalities requires direct measurements of cerebral hemodynamics and MAP. Several near-infrared diffuse optical instruments have been developed in our laboratory for hemodynamic measurements including near-infrared spectroscopy (NIRS), diffuse correlation spectroscopy (DCS), hybrid NIRS/DCS, and dual-wavelength DCS flow-oximeter. We utilized these noninvasive technologies to quantify CBF and cerebral oxygenation in different populations under different physiological conditions/manipulations. A commercial finger plethysmograph was used to continuously monitor MAP. For investigating …

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