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Full-Text Articles in Biomedical Engineering and Bioengineering

A Multimodal Approach To Investigate Brain Reorganization After Spinal Cord Injury Using Functional Magnetic Resonance Imaging And Functional Near-Infrared Spectroscopy, Keerthana Deepti Karunakaran May 2019

A Multimodal Approach To Investigate Brain Reorganization After Spinal Cord Injury Using Functional Magnetic Resonance Imaging And Functional Near-Infrared Spectroscopy, Keerthana Deepti Karunakaran

Dissertations

Traumatic Spinal Cord Injury (SCI) results in structural and functional neurological changes at both the brain and the level of the spinal cord. Anatomical studies indicate decreased grey matter volume in sensorimotor and non-sensorimotor regions of the cortex following SCI; whereas, neurophysiological findings mostly report altered functional activity in the sensorimotor nodes of the cortex, subcortex, and cerebellum. Therefore, it is currently unknown whether tissue atrophy observed in non-motor related areas has any concomitant functional consequences. Furthermore, the neural underpinnings of adaptive neuroplasticity after SCI is not well-defined in the current literature. Hence, this dissertation is a pioneer study investigating ...


Brain Image Clustering By Wavelet Energy And Cbsso Optimization Algorithm, Hasan Hosseinzadeh, Mohammad Sedaghat Apr 2019

Brain Image Clustering By Wavelet Energy And Cbsso Optimization Algorithm, Hasan Hosseinzadeh, Mohammad Sedaghat

Journal of Mind and Medical Sciences

Previously, the diagnosis of brain abnormality was significantly important in the saving of social and hospital resources. Wavelet energy is known as an effective feature detection which has great efficiency in different utilities. This paper suggests a new method based on wavelet energy to automatically classify magnetic resonance imaging (MRI) brain images into two groups (normal and abnormal), utilizing support vector machine (SVM) classification based on chaotic binary shark smell optimization (CBSSO) to optimize the SVM weights.

The results of the suggested CBSSO-based KSVM are compared favorably to several other methods in terms of better sensitivity and authenticity. The proposed ...


Manganese-Enhanced Magnetic Resonance Imaging: Overview And Central Nervous System Applications With A Focus On Neurodegeneration, Ryan A. Cloyd, Shon A. Koren, Jose F. Abisambra Dec 2018

Manganese-Enhanced Magnetic Resonance Imaging: Overview And Central Nervous System Applications With A Focus On Neurodegeneration, Ryan A. Cloyd, Shon A. Koren, Jose F. Abisambra

Physiology Faculty Publications

Manganese-enhanced magnetic resonance imaging (MEMRI) rose to prominence in the 1990s as a sensitive approach to high contrast imaging. Following the discovery of manganese conductance through calcium-permeable channels, MEMRI applications expanded to include functional imaging in the central nervous system (CNS) and other body systems. MEMRI has since been employed in the investigation of physiology in many animal models and in humans. Here, we review historical perspectives that follow the evolution of applied MRI research into MEMRI with particular focus on its potential toxicity. Furthermore, we discuss the more current in vivo investigative uses of MEMRI in CNS investigations and ...


Neuroimaging Biomarkers Of Mtor Inhibition On Vascular And Metabolic Functions In Aging Brain And Alzheimer’S Disease, Jennifer Lee, Lucille M. Yanckello, David Ma, Jared D. Hoffman, Ishita Parikh, Scott Thalman, Bjoern Bauer, Anika M. S. Hartz, Fahmeed Hyder, Ai-Ling Lin Jul 2018

Neuroimaging Biomarkers Of Mtor Inhibition On Vascular And Metabolic Functions In Aging Brain And Alzheimer’S Disease, Jennifer Lee, Lucille M. Yanckello, David Ma, Jared D. Hoffman, Ishita Parikh, Scott Thalman, Bjoern Bauer, Anika M. S. Hartz, Fahmeed Hyder, Ai-Ling Lin

Pharmacology and Nutritional Sciences Faculty Publications

The mechanistic target of rapamycin (mTOR) is a nutrient sensor of eukaryotic cells. Inhibition of mechanistic mTOR signaling can increase life and health span in various species via interventions that include rapamycin and caloric restriction (CR). In the central nervous system, mTOR inhibition demonstrates neuroprotective patterns in aging and Alzheimer’s disease (AD) by preserving mitochondrial function and reducing amyloid beta retention. However, the effects of mTOR inhibition for in vivo brain physiology remain largely unknown. Here, we review recent findings of in vivo metabolic and vascular measures using non-invasive, multimodal neuroimaging methods in rodent models for brain aging and ...


Computer-Aided Diagnoses (Cad) System: An Artificial Neural Network Approach To Mri Analysis And Diagnosis Of Alzheimer's Disease (Ad), Berizohar Padilla Cerezo Dec 2017

Computer-Aided Diagnoses (Cad) System: An Artificial Neural Network Approach To Mri Analysis And Diagnosis Of Alzheimer's Disease (Ad), Berizohar Padilla Cerezo

Master's Theses and Project Reports

Alzheimer’s disease (AD) is a chronic and progressive, irreversible syndrome that deteriorates the cognitive functions. Official death certificates of 2013 reported 84,767 deaths from Alzheimer’s disease, making it the 6th leading cause of death in the United States. The rate of AD is estimated to double by 2050. The neurodegeneration of AD occurs decades before symptoms of dementia are evident. Therefore, having an efficient methodology for the early and proper diagnosis can lead to more effective treatments.

Neuroimaging techniques such as magnetic resonance imaging (MRI) can detect changes in the brain of living subjects. Moreover, medical imaging ...


Dual-Tuned Removable Common-Mode Current Trap For Mri, Angel G. Enriquez, Joseph V. Rispoli Aug 2017

Dual-Tuned Removable Common-Mode Current Trap For Mri, Angel G. Enriquez, Joseph V. Rispoli

The Summer Undergraduate Research Fellowship (SURF) Symposium

Magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) are preferred methods of gathering information from the body due to their non-invasive approach of obtaining a diagnosis. MRI can obtain spatial mappings from a region of interest, while MRS can obtain metabolic information from different elements. Dual-tuned radiofrequency (RF) coils are able to capture signals produced by both hydrogen atoms and a second atom of interest. Unwanted shield currents occur in these scans, which can cause image distortion, while the high energy dissipated can create harmful heat, which can injure the patient. These shield currents, also known as common-mode currents ...


Gui For Mri-Compatible Neural Stimulator And Recorder, Soo Han Soon, Nishant Babaria, Ranajay Mandal, Zhongming Liu Aug 2017

Gui For Mri-Compatible Neural Stimulator And Recorder, Soo Han Soon, Nishant Babaria, Ranajay Mandal, Zhongming Liu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) are useful tools to analyze brain activities given active stimulation. However, the electromagnetic noise from the MRI distorts the brain signal recording and damages the subject with excessive heat generated on the electrodes attached to the skin. MRI-compatible recording and stimulation systems previously developed at LIBI lab were capable of removing the electromagnetic noise during the imaging process. Previously, the hardware systems had required the integrative software that could control both circuits simultaneously and enable users to easily change recording and stimulation parameters. Graphical user interface (GUI) programmed with computer language informed ...


Computer-Assisted Characterization Of Prostate Cancer On Magnetic Resonance Imaging, Derek J. Soetemans Mar 2017

Computer-Assisted Characterization Of Prostate Cancer On Magnetic Resonance Imaging, Derek J. Soetemans

Electronic Thesis and Dissertation Repository

Prostate cancer (PCa) is one of the most prevalent cancers among men. Early diagnosis can improve survival and reduce treatment costs. Current inter-radiologist variability for detection of PCa is high. The use of multi-parametric magnetic resonance imaging (mpMRI) with machine learning algorithms has been investigated both for improving PCa detection and for PCa diagnosis. Widespread clinical implementation of computer-assisted PCa lesion characterization remains elusive; critically needed is a model that is validated against a histologic reference standard that is densely sampled in an unbiased fashion. We address this using our technique for highly accurate fusion of mpMRI with whole-mount digitized ...


A Magnetic Resonance Compatible Knee Extension Ergometer, Youssef Jaber Jan 2017

A Magnetic Resonance Compatible Knee Extension Ergometer, Youssef Jaber

Masters Theses

The product of this thesis aims to enable the study of the biochemical and physical dynamics of the lower limbs at high levels of muscle tension and fast contraction speeds. This is accomplished in part by a magnetic resonance (MR) compatible ergometer designed to apply a load as a torque of up to 420 Nm acting against knee extension at speeds as high as 4.7 rad/s. The system can also be adapted to apply the load as a force of up to 1200 N acting against full leg extension. The ergometer is designed to enable the use of ...


A Structural And Functional Analysis Of Human Brain Mri With Attention Deficit Hyperactivity Disorder, Arjun A. Watane Jan 2017

A Structural And Functional Analysis Of Human Brain Mri With Attention Deficit Hyperactivity Disorder, Arjun A. Watane

Honors Undergraduate Theses

Attention Deficit Hyperactivity Disorder (ADHD) affects 5-10% of children worldwide. Its effects are mainly behavioral, manifesting in symptoms such as inattention, hyperactivity, and impulsivity. If not monitored and treated, ADHD may adversely affect a child's health, education, and social life. Furthermore, the neurological disorder is currently diagnosed through interviews and opinions of teachers, parents, and physicians. Because this is a subjective method of identifying ADHD, it is easily prone to error and misdiagnosis. Therefore, there is a clear need to develop an objective diagnostic method for ADHD.

The focus of this study is to explore the use of machine ...


A Cad System For Early Diagnosis Of Autism Using Different Imaging Modalities., Marwa Maher Tawfik Ismail Dec 2016

A Cad System For Early Diagnosis Of Autism Using Different Imaging Modalities., Marwa Maher Tawfik Ismail

Electronic Theses and Dissertations

The term “autism spectrum disorder” (ASD) refers to a collection of neuro-developmental disorders that affect linguistic, behavioral, and social skills. Autism has many symptoms, most prominently, social impairment and repetitive behaviors. It is crucial to diagnose autism at an early stage for better assessment and investigation of this complex syndrome. There have been a lot of efforts to diagnose ASD using different techniques, such as imaging modalities, genetic techniques, and behavior reports. Imaging modalities have been extensively exploited for ASD diagnosis, and one of the most successful ones is Magnetic resonance imaging(MRI),where it has shown promise for the ...


A Multi-Facetted Visual Analytics Tool For Exploratory Analysis Of Human Brain And Function Datasets, Diego A. Angulo, Cyril Schneider, James H. Oliver, Nathalie Charpak, Jose T. Hernandez Aug 2016

A Multi-Facetted Visual Analytics Tool For Exploratory Analysis Of Human Brain And Function Datasets, Diego A. Angulo, Cyril Schneider, James H. Oliver, Nathalie Charpak, Jose T. Hernandez

Mechanical Engineering Publications

Brain research typically requires large amounts of data from different sources, and often of different nature. The use of different software tools adapted to the nature of each data source can make research work cumbersome and time consuming. It follows that data is not often used to its fullest potential thus limiting exploratory analysis. This paper presents an ancillary software tool called BRAVIZ that integrates interactive visualization with real-time statistical analyses, facilitating access to multi-facetted neuroscience data and automating many cumbersome and error-prone tasks required to explore such data. Rather than relying on abstract numerical indicators, BRAVIZ emphasizes brain images ...


Validation Strategies Supporting Clinical Integration Of Prostate Segmentation Algorithms For Magnetic Resonance Imaging, Maysam Shahedi Bagh Khandan Mar 2016

Validation Strategies Supporting Clinical Integration Of Prostate Segmentation Algorithms For Magnetic Resonance Imaging, Maysam Shahedi Bagh Khandan

Electronic Thesis and Dissertation Repository

Segmentation of the prostate in medical images is useful for prostate cancer diagnosis and therapy guidance. However, manual segmentation of the prostate is laborious and time-consuming, with inter-observer variability. The focus of this thesis was on accuracy, reproducibility and procedure time measurement for prostate segmentation on T2-weighted endorectal magnetic resonance imaging, and assessment of the potential of a computer-assisted segmentation technique to be translated to clinical practice for prostate cancer management. We collected an image data set from prostate cancer patients with manually-delineated prostate borders by one observer on all the images and by two other observers on a subset ...


Mri Hip Joint Traction Device, Rawan Alfadly, Carla Gomez, Sara Um Jan 2016

Mri Hip Joint Traction Device, Rawan Alfadly, Carla Gomez, Sara Um

Capstone Design Expo Posters

Radiologists commonly use contrast agents to improve resolution and acuity when employing MRI (Magnetic Resonance Imaging). Introducing MRI contrast agents to the tissue in the innermost part of the femoroacetabular joint is extremely difficult because the anatomy prevents the contrast agents from infiltrating those surfaces. Therefore, getting the ideal image resolution and making diagnosis of the hip is difficult. The objective was to design a product that would successfully distract one hip joint while also stabilizing the patient’s pelvis to improve visualization so that physicians are able to better diagnose the hip. The deliverables included a preliminary model that ...


Toward Magnetic Resonance Only Treatment Planning: Distortion Mitigation And Image-Guided Radiation Therapy Validation, Ryan Glen Price Jan 2016

Toward Magnetic Resonance Only Treatment Planning: Distortion Mitigation And Image-Guided Radiation Therapy Validation, Ryan Glen Price

Wayne State University Dissertations

While MR-only treatment planning has shown promise, there are still several well-known challenges that are currently limiting widespread clinical implementation.

Firstly, MR images are affected by both patient-induced and system-level geometric distortions that can significantly degrade treatment planning accuracy. . In addition, the availability of comprehensive distortion analysis software is currently limited. Also while many groups have been working toward a synthetic CT solution, further study is needed on the implementation of synCTs as the reference datasets for linac-based image-guided radiation therapy (IGRT) to help determine their robustness in an MR-only workflow.

A 36×43×2 cm3 phantom with 255 known ...


Impact Of Acl Injury On Patellar Cartilage Thickness, Ethan Leveillee Jan 2016

Impact Of Acl Injury On Patellar Cartilage Thickness, Ethan Leveillee

Graduate College Dissertations and Theses

ACL injury has been shown to have long-lasting and severe consequences on the different structures of the knee such as the articular cartilage and meniscus. Cartilage thickness changes in particular are indicative of osteoarthritic changes in the tibiofemoral joint. While there has been significant research focused on cartilage changes of the tibia and femur, there has been little work looking at patellar cartilage. The following goals were set forth for this study. First, to establish a robust coordinate system to accurately determine the location and orientation of the patella. Secondly, to determine the effects of ACL injury on patellar cartilage ...


Applications Of Novel Mri Technologies In Tissue Engineering And Disease Diagnosis, Vahid Khalilzad-Sharghi Oct 2014

Applications Of Novel Mri Technologies In Tissue Engineering And Disease Diagnosis, Vahid Khalilzad-Sharghi

Biological Systems Engineering--Dissertations, Theses, and Student Research

Magnetic resonance imaging (MRI) and magnetic resonance elastography (MRE) are increasingly under investigation to explore their potential role in establishing effective evaluation methods for the procedure of tissue regeneration carried out in vitro, in vivo, and in disease diagnosis. To this end, there is a continuous pursuit of novel tools both in vitro and in vivo. For instance, there is a great need for the development and evaluation of an MR-compatible incubation system that enables simultaneous monitoring and culturing of cell and tissue constructs using MRI techniques. Such an imagingcompatible incubation system eliminates exposing the culture to the risks of ...


Advances In Image Acquisition And Filtering For Mri Neuroimaging At 7 Tesla, Andrew T. Curtis Sep 2014

Advances In Image Acquisition And Filtering For Mri Neuroimaging At 7 Tesla, Andrew T. Curtis

Electronic Thesis and Dissertation Repository

Performing magnetic resonance imaging at high magnetic field strength promises many improvements over low fields that are of direct benefit in functional neuroimaging. This includes the possibility of improved signal-to-noise levels, and increased BOLD functional contrast and spatial specificity. However, human MRI at 7T and above suffers from unique engineering challenges that limit the achievable gains. In this thesis, three technological developments are introduced, all of which address separate issues associated with functional magnetic resonance neuroimaging at very high magnetic field strengths.

First, the image homogeneity problem is addressed by investigating methods of RF shimming — modifying the excitation portion of ...


Changes In The Ultrastructural Features Of Estrogen Deficient Ovine Bone, Peter Mauer Jan 2014

Changes In The Ultrastructural Features Of Estrogen Deficient Ovine Bone, Peter Mauer

PhD theses

Osteoporosis is “a skeletal disorder characterised by compromised bone strength predis- posing to an increased risk of fracture” (NIH, 2001). Every second woman and every fifth man will suffer an osteoporotic fracture (Kanis et al., 2000). Of all people that suffer an age-related fracture, the current gold standard of osteoporosis diagnosis, DEXA scanning, misclassifies 80% of them to be non-osteoporotic (Sanders et al., 2006). Bone quantity is easily measured, however, bone strength is an interplay of bone quantity and quality — and the latter is hard to determine. More reliable clinical methods to diagnose osteoporosis are needed as well as widening ...


Measuring Brain Iron In Healthy Controls And Accessing Venous Abnormalities In Parkinson's Disease Using Mri, Manju Liu Jan 2014

Measuring Brain Iron In Healthy Controls And Accessing Venous Abnormalities In Parkinson's Disease Using Mri, Manju Liu

Wayne State University Dissertations

Iron plays a key role in a number of brain cellular processes. However, abnormal brain iron regulation correlates with a number of neurodegenerative diseases such as Parkinson's disease, multiple sclerosis and so forth. To further elucidate the involvement of iron in neurodegenerative disorders, a robust in vivo quantitative non-invasive assessment of normal brain iron deposition over time is essential. A variety of magnetic resonance imaging (MRI) methods have been used to quantify iron both in vivo and in vitro non-invasively. We first created the baseline of phase value and ∆R2^* as a function of age in seven gray matter ...


Patient-Specific Modeling Of Adult Acquired Flatfoot Deformity Before And After Surgery, Edward Meade Spratley Dec 2013

Patient-Specific Modeling Of Adult Acquired Flatfoot Deformity Before And After Surgery, Edward Meade Spratley

Theses and Dissertations

The use of computational modeling is an increasingly commonplace technique for the investigation of biomechanics in intact and pathological musculoskeletal systems. Moreover, given the robust and repeatable nature of computer simulation and the prevalence of software techniques for accurate 3-D reconstructions of tissues, the predictive power of these models has increased dramatically. However, there are no patient-specific kinematic models whose function is dictated solely by physiologic soft-tissue constraints, articular shape and contact, and without idealized joint approximations. Moreover, very few models have attempted to predict surgical effects combined with postoperative validation of those predictions. Given this, it is not surprising ...


Automated Segmentation Of Left And Right Ventricles In Mri And Classification Of The Myocarfium Abnormalities, Cyrus (Mohammad Saleh) Nambakhsh Sep 2013

Automated Segmentation Of Left And Right Ventricles In Mri And Classification Of The Myocarfium Abnormalities, Cyrus (Mohammad Saleh) Nambakhsh

Electronic Thesis and Dissertation Repository

A fundamental step in diagnosis of cardiovascular diseases, automated left and right ventricle (LV and RV) segmentation in cardiac magnetic resonance images (MRI) is still acknowledged to be a difficult problem. Although algorithms for LV segmentation do exist, they require either extensive training or intensive user inputs. RV segmentation in MRI has yet to be solved and is still acknowledged a completely unsolved problem because its shape is not symmetric and circular, its deformations are complex and varies extensively over the cardiac phases, and it includes papillary muscles. In this thesis, I investigate fast detection of the LV endo- and ...


Ex Vivo Diffusion Tensor Imaging Of Spinal Cord Injury In Rats Of Varying Degrees Of Severity, Michael Jirjis, Shekar N. Kurpad, Brian D. Schmit Sep 2013

Ex Vivo Diffusion Tensor Imaging Of Spinal Cord Injury In Rats Of Varying Degrees Of Severity, Michael Jirjis, Shekar N. Kurpad, Brian D. Schmit

Biomedical Engineering Faculty Research and Publications

The aim of this study was to characterize magnetic resonance diffusion tensor imaging (DTI) in proximal regions of the spinal cord following a thoracic spinal cord injury (SCI). Sprague–Dawley rats (n = 40) were administered a control, mild, moderate, or severe contusion injury at the T8 vertebral level. Six direction diffusion weighted images (DWIs) were collected ex vivo along the length of the spinal cord, with an echo/repetition time of 31.6 ms/14 sec and b = 500 sec/mm2. Diffusion metrics were correlated to hindlimb motor function. Significant differences were found for whole cord region of interest (ROI ...


Detecting Activity-Evoked Ph Changes In Human Brain, Hye Young Heo Jul 2013

Detecting Activity-Evoked Ph Changes In Human Brain, Hye Young Heo

Theses and Dissertations

Localized pH changes have been suggested to occur in the brain during normal function. However, a lack of methods for non-invasively measuring pH with high spatial and temporal resolution limits current knowledge of brain pH dynamics. Here I report that a magnetic resonance imaging (MRI) strategy named T1 relaxation in the rotating frame (T) is sufficiently sensitive to detect widespread pH changes in the mouse and human brain evoked by systemically manipulating carbon dioxide (CO2) or bicarbonate (HCO3). Moreover, T detected changes suggesting a localized acidosis in the human visual cortex induced by a flashing ...


Accelerating Mri Data Acquisition Using Parallel Imaging And Compressed Sensing, Haifeng Wang Dec 2012

Accelerating Mri Data Acquisition Using Parallel Imaging And Compressed Sensing, Haifeng Wang

Theses and Dissertations

Magnetic Resonance Imaging (MRI) scanners are one of important medical instruments, which can achieve more information of soft issues in human body than other medical instruments, such as Ultrasound, Computed Tomography (CT), Single Photon Emission Computed Tomography (SPECT), Positron Emission Tomography (PET), etc. But MRI's scanning is slow for patience of doctors and patients. In this dissertation, the author proposes some methods of parallel imaging and compressed sensing to accelerate MRI data acquisition. Firstly, a method is proposed to improve the conventional GRAPPA using cross-sampled auto-calibration data. This method use cross-sampled auto-calibration data instead of the conventional parallel-sampled auto-calibration ...


Novel Phantoms And Post-Processing For Diffusion Spectrum Imaging, Vaibhav Juneja May 2012

Novel Phantoms And Post-Processing For Diffusion Spectrum Imaging, Vaibhav Juneja

UT GSBS Dissertations and Theses (Open Access)

High Angular Resolution Diffusion Imaging (HARDI) techniques, including Diffusion Spectrum Imaging (DSI), have been proposed to resolve crossing and other complex fiber architecture in the human brain white matter. In these methods, directional information of diffusion is inferred from the peaks in the orientation distribution function (ODF). Extensive studies using histology on macaque brain, cat cerebellum, rat hippocampus and optic tracts, and bovine tongue are qualitatively in agreement with the DSI-derived ODFs and tractography. However, there are only two studies in the literature which validated the DSI results using physical phantoms and both these studies were not performed on a ...


Controlling Dimensionality In A Systems Approach To Dynamic Multimodal Functional Brain Imaging, Srinivas Laxminarayan, Manu Ben Jonny, Solomon Diamond, Dana Brooks, Gilead Tadmore, Eric Miller, David Boas Apr 2012

Controlling Dimensionality In A Systems Approach To Dynamic Multimodal Functional Brain Imaging, Srinivas Laxminarayan, Manu Ben Jonny, Solomon Diamond, Dana Brooks, Gilead Tadmore, Eric Miller, David Boas

Dana Brooks

The complementary spatial, temporal and specificity advantages of MRI, EEG, MEG, PET and DOT for functional brain imaging motivate interest in multimodal functional brain imaging. State-variable dynamical systems modeling of neural activity and its relation to local hemodynamics further coupled with autonomic physiology offers enhanced spatiotemporal resolution and insight into physiological signals and mechanisms. However, such a model also implies an explosion of state dimension. We discuss strategies for controlling this high dimensionality based on subspace approaches applied to the observed data and the model structure, and also describe some implications for understanding human brain function.


Spin-Labeling Magnetic Resonance Imaging Detects Increased Myocardial Blood Flow After Endothelial Cell Transplantation In The Infarcted Heart, Hualei Zhang, Hui Qiao, Rachel S. Frank, Bin Huang, Kathleen J. Propert, Susan S. Margulies, Victor A. Ferrari, Jonathan A. Epstein, Rong Zhou Feb 2012

Spin-Labeling Magnetic Resonance Imaging Detects Increased Myocardial Blood Flow After Endothelial Cell Transplantation In The Infarcted Heart, Hualei Zhang, Hui Qiao, Rachel S. Frank, Bin Huang, Kathleen J. Propert, Susan S. Margulies, Victor A. Ferrari, Jonathan A. Epstein, Rong Zhou

Departmental Papers (BE)

Background

We quantified absolute myocardial blood flow (MBF) using a spin-labeling MRI (SL-MRI) method after transplantation of endothelial cells (ECs) into the infarcted heart. Our aims were to study the temporal changes in MBF in response to EC transplantation and to compare regional MBF with contractile function (wall motion) and microvascular density.

Methods and Result

We first validated the SL-MRI method with the standard microsphere technique in normal rats. We then induced myocardial infarction in athymic rats and injected 5 million ECs (human umbilical vein endothelial cells) suspended in Matrigel or Matrigel alone (vehicle) along the border of the blanched ...


Computer-Aided, Multi-Modal, And Compression Diffuse Optical Studies Of Breast Tissue, David R. Busch Jr Dec 2011

Computer-Aided, Multi-Modal, And Compression Diffuse Optical Studies Of Breast Tissue, David R. Busch Jr

Publicly Accessible Penn Dissertations

Diffuse Optical Tomography and Spectroscopy permit measurement of important physiological parameters non-invasively through ~10 cm of tissue. I have applied these techniques in measurements of human breast and breast cancer. My thesis integrates three loosely connected themes in this context: multi-modal breast cancer imaging, automated data analysis of breast cancer images, and microvascular hemodynamics of breast under compression. As per the first theme, I describe construction, testing, and the initial clinical usage of two generations of imaging systems for simultaneous diffuse optical and magnetic resonance imaging. The second project develops a statistical analysis of optical breast data from many spatial ...


Chemical And Biological Strategies For Improving The Sensitivity Of Spio-Enhanced Mr Imaging, Andrew Elias Aug 2011

Chemical And Biological Strategies For Improving The Sensitivity Of Spio-Enhanced Mr Imaging, Andrew Elias

Publicly Accessible Penn Dissertations

The prevalence of cancer has seen significant growth over the last three decades, with the American Cancer Society now reporting that one in every three Americans will be afflicted with some form of cancer in their lifetime. The debilitating effects of cancer permeate beyond obvious biological ramifications, often adversely affecting patients on emotional and financial levels as well. While significant progress has been made in diagnosing and treating cancer, advancements are still needed in detecting and treating cancers at earlier stages, where clinical outcomes will be more favorable. The field of cellular and molecular imaging has emerged as a cutting-edge ...