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Cellular Mechanisms Of Spinal Motoneuron Hypoexcitability Underlying Dynapenia In Aging, Ibrahim Abdul Halim Jan 2025

Cellular Mechanisms Of Spinal Motoneuron Hypoexcitability Underlying Dynapenia In Aging, Ibrahim Abdul Halim

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Age-related weakness remains poorly understood as the underlying mechanisms remain unclear. While synaptic input and muscular changes have been investigated with age, intrinsic motoneuron excitability alterations are often overlooked. This thesis provides the first direct assessment of intrinsic excitability and ion channel properties of spinal α-MNs from male and female mice across three ages: young, middle aged, and old. Our findings reveal a decline in intrinsic excitability of motoneurons with age in both sexes. Mechanistic analysis shows sex specific differences: female motoneurons exhibit increased dendritic size, hyperpolarized RMP, and SK channel overactivation, whereas males show only SK overactivation with age. …


Comparative Analysis Of Motoneuronal C-Bouton Structural Alterations In Als And Aging, Shelby Nicole Ward Jan 2024

Comparative Analysis Of Motoneuronal C-Bouton Structural Alterations In Als And Aging, Shelby Nicole Ward

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Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease characterized by motor neuron (MN) death resulting in paralysis and eventually death. ALS has greater prevalence in older populations sharing characteristics with aging like muscle weakness and MN type specific degeneration. MNs innervate skeletal muscles and control muscle contraction through their excitability which is altered in both conditions. C-Boutons are a cholinergic, excitatory synaptic input to MNs and have been studied in ALS and aging but have produced inconsistent findings and undesired gaps. We used immunohistochemistry to label mouse lumbar spinal cord and separate MN types. 60x imaging and automated analysis was …


Sex-Driven Alterations In Aging Alpha Motoneurons: Exploring Size, Type, Density, And Kv2.1 Channel Expression, Kalin R. Gerber Jan 2024

Sex-Driven Alterations In Aging Alpha Motoneurons: Exploring Size, Type, Density, And Kv2.1 Channel Expression, Kalin R. Gerber

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This research explores how motor neurons (MNs) and Kv2.1 clustering change with age, emphasizing sex differences and MN subtypes. We found that MN density decreases with age in both sexes, while soma size increases in male mice. FF MNs were the most affected, and old weak mice had smaller MNs than their stronger counterparts, underscoring FF MN vulnerability. Baseline studies revealed that FF and FI MNs have larger Kv2.1 clusters compared to FR and S MNs. Female mice had smaller, denser Kv2.1 clusters than male mice, suggesting less clustering in females. With age, Kv2.1 clusters grew larger but became less …


Brain Morphometry From Neuroimaging As A Biomarker For Alzheimer's Disease, Nonyelum Benedicta Aniebo Jan 2023

Brain Morphometry From Neuroimaging As A Biomarker For Alzheimer's Disease, Nonyelum Benedicta Aniebo

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Alzheimer’s disease (AD) is the seventh leading cause of death globally with an estimated 6.5 million Americans aged 65 and above living with Alzheimer’s dementia in 2022 and at a projected national cost of $321 billion. AD is characterized by a progressive and irreversible neurodegenerative dysfunction with clinical symptoms such as deterioration in cognition and memory loss. The Alzheimer’s Disease Neuroimaging Initiative (ADNI) is a multi-site, public-private global research initiative that supports both investigation and development of treatments that slow or terminate AD progression. The study included 60 participants, comprising 30 AD and 30 control cohorts respectively. All participants were …


Development Of Gene Regulatory Elements For Biosensing Applications, Mallory N. Bates Jan 2022

Development Of Gene Regulatory Elements For Biosensing Applications, Mallory N. Bates

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21% of U.S adults experienced mental illnesses in 2020. Nearly 1 in 4 active- duty military personnel showed signs of mental health conditions in 2014 [89]. Mental health can be identified in the body by different biomarkers. These biomarkers potentially could be controlled by riboswitches, which could help mental illnesses and regulate diseases. Riboswitches are desirable in these cases due to responding without affecting vital functions. Riboswitches are located in mRNA and switch “ON” or “OFF” depending on the concentration of a biomarker [13]. In this research, riboswitches were re-engineered to take a known riboswitch and control its response in …


Global Joint Registry: Analysis Of Revision Hip Arthroplasty Data, Alicia M. Runser Jan 2020

Global Joint Registry: Analysis Of Revision Hip Arthroplasty Data, Alicia M. Runser

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Total hip arthroplasty (THA) has become well-known as being one of the most successful procedures with much long-term positive clinical results. However, revision surgeries are still required. The four most common failure modes for THAs, “reasons for revision”, are loosening, dislocation or instability, fracture, and infection. The goal of a hip arthroplasty register is to gather information on patients that undergo a total hip arthroplasty and factors pertaining to their surgery which may affect their outcome for future years such as the reason for revision. Analysis of this data can help with the allocation of healthcare funds and the efficacy …


Observing P300 Amplitudes In Multiple Sensory Channels Using Cognitive Probing, Cody Lee Wintermute Jan 2020

Observing P300 Amplitudes In Multiple Sensory Channels Using Cognitive Probing, Cody Lee Wintermute

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High cognitive workload occurs when excessive working memory resources have been deployed to resolve sensory and cognitive processing, resulting in decremented task performance. The P300 event-related potential (ERP) component has shown sensitivity to cognitive load, and it was hypothesized that an attenuated P300 amplitude could be indicative of high cognitive load. We tested this hypothesis by having eight participants complete two continual performance tasks at increasing workload levels while simultaneously performing an oddball task, evoking P300 ERPs in either the auditory or tactile sensory channel. In our experiment, electroencephalographic recordings were collected over the parietal region to observe the P300 …


Single-Pixel Camera Based Spatial Frequency Domain Imaging For Non-Contact Tissue Characterization, Alec M. Petrack Jan 2020

Single-Pixel Camera Based Spatial Frequency Domain Imaging For Non-Contact Tissue Characterization, Alec M. Petrack

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Optical imaging has demonstrated potential as a medical imaging modality for measuring tissue functionality. Recently, interest in fluorescence guided surgery has emerged from improvements in optical imaging that have allowed real-time feedback. Of the optical imaging modalities, spatial frequency domain imaging (SFDI) has gained a lot of interest. Unlike spectroscopic techniques, such as functional near infrared spectroscopy (fNIRS) and frequency domain spectroscopy that measure bulk tissue properties, SFDI quantifies tissue functionality locally and wide field making it practical for clinical applications. Unfortunately, traditional SFDI systems use multi-pixel detectors, which may not exhibit ideal spectral characteristics, have limited sensitivity, be expensive, …


Visual Sampling With The Eeg Alpha Oscillation, Kevin Eugene Alexander Jan 2020

Visual Sampling With The Eeg Alpha Oscillation, Kevin Eugene Alexander

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The posterior alpha rhythm, seen in human electroencephalograms (EEG), is posited to originate from cycling inhibitory/excitatory states of visual relay cells in the thalamus, which could result in discrete sampling of visual information. Here, we tested this hypothesis by presenting light flashes at perceptual threshold intensity through closed eyelids to 20 participants during times of spontaneous alpha oscillations. Alpha phase and amplitude were calculated relative to each individual’s retina-to-V1 conduction delay, estimated by the individuals’ C1 visual-evoked potential latency. Our results show that an additional 20.96% of stimuli are observed when afferenting at V1 during an alpha wave trough (272.41°) …


Kv2.1 Channel Clustering In The Sod1-G93a Mouse Model Of Als, Joshua Christopher Harris Jan 2020

Kv2.1 Channel Clustering In The Sod1-G93a Mouse Model Of Als, Joshua Christopher Harris

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Kv2.1 channels mediate slow-activating K+ rectifier current within the membrane of spinal motoneurons (MNs), and they are known to co-localize with other synapses and ion channels. Although Kv2.1 channels are suggested to regulate MN excitability, little research has gone into investigating its potential contribution to MN-altered excitability in Amyotrophic Lateral Sclerosis (ALS). Using the male SOD1-G93A mouse model of ALS, we examined Kv2.1 cluster area and density in lumbar MNs at four key stages of disease progression. In our experiments, MNs were separated by type via SK3 immunoreactivity in order to isolate and compare the responses of disease-resistant (slow; SK3+) …


Assessing The Role Of Polyphenols As A Vascular Protectant Against Drug Induced Vascular Injury, Anson Jacob Oommen Jan 2019

Assessing The Role Of Polyphenols As A Vascular Protectant Against Drug Induced Vascular Injury, Anson Jacob Oommen

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Vascular injury is identified during pre-clinical toxicity testing within certain pharmacological classes of drug candidates and induces degenerative and hyperplastic changes in endothelial (ECs) and vascular smooth muscle (VSMCs) cells. This drug-induced vascular injury has been show as a side-effect caused by various classes of drugs, including, antibacterial (e.g., azithromycin), anti-malarial (e.g., quinoline), anti-viral (e.g., anti-hepatitis C virus interferons) and nonsteroidal anti-inflammatory drugs (e.g., ibuprofen), and affects normal cardiovascular function and can further lead to various cardiovascular conditions like arrhythmia, cardiac arrest, high blood pressure, and even heart attack. The search for agents capable of reducing vascular injury side-effects by …


Characterization Of In-Vivo Damage In Implantable Cardiac Devices And The Lead Residual Properties, Anmar Mahdi Salih Jan 2019

Characterization Of In-Vivo Damage In Implantable Cardiac Devices And The Lead Residual Properties, Anmar Mahdi Salih

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Approximately, 92.1 million patients in the US suffer from cardiovascular diseases with an estimated healthcare cost of over $300 billion; out of which at least one million patients have Cardiac Implantable Electronics Devices (CIED). CIED represented by pacemakers, Implantable Cardioversion Defibrillator (ICD), and Cardiac Resynchronization Therapy (CRT) are exposed to in-vivo damage. These damages are complex and composed on multiple levels and present challenges while assessing their combined extent. Since 2004, more than one hundred recalls were reported for cardiac devices. ICD devices had the majority with 40.8% recalls, pacemaker recall percentage was 14.5%, CRT recall percentage was12.7%, leads recalls …


Quantification Of Optical Parameters Using Frequency Domain Functional Near-Infrared Spectroscopy (Fd-Fnirs), Christopher W. Davies Jan 2019

Quantification Of Optical Parameters Using Frequency Domain Functional Near-Infrared Spectroscopy (Fd-Fnirs), Christopher W. Davies

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Near infrared spectroscopy (NIRS) is a non-invasive technique that uses near-infrared light and hemoglobin as the contrast to characterize tissue optical properties, namely optical absorption [����] and scattering [����′ ]. Through this characterization, it is possible to obtain information about the tissue’s oxygenated (HbO) and deoxygenated (Hb) hemoglobin concentrations and oxygen saturation which are important physiological markers for diagnosis and intervention monitoring. Many commercial devices use a continuous wave approach (CW-fNIRS), a technique that simply relies on intensity changes from a constant power laser to determine only relative changes in oxygenation. This is a significant limitation for clinical settings where …


Mechanical Stresses On Nasal Mucosa Using Nose-On-Chip Model, Zachary Edward Brooks Jan 2019

Mechanical Stresses On Nasal Mucosa Using Nose-On-Chip Model, Zachary Edward Brooks

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The objective of this research was to design and fabricate a nose-on-chip device and bi-directional airflow system that models flow within the nasal cavity to investigate how airflow induced mechanical stresses impact nasal secretion rates and cytoskeletal remodeling. This research hypothesizes that the airflow induced shear stresses on the nasal mucosa will influence mucus production and the cytoskeleton of the cells. The RPMI 2650 cell line was used to model the nasal mucosa. The system was used to replicate the wall shear stresses (WSS) and wall shear forces (WSF) present in the anterior region of the nose. The WSS and …


Monitoring Cerebral Functional Response Using Scmos-Based High Density Near Infrared Spectroscopic Imaging, Dharminder Singh Langri Jan 2019

Monitoring Cerebral Functional Response Using Scmos-Based High Density Near Infrared Spectroscopic Imaging, Dharminder Singh Langri

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Neurovascular coupling is an important concept that indicates the direct link between neuronal electrical firing with the vascular hemodynamic changes. Functional Near Infrared Spectroscopy (fNIRS) can measure changes in cerebral vascular parameters of oxy-hemoglobin and deoxyhemoglobin concentrations and thus can provide neuronal activity through neurovascular coupling. Currently many commercial fNIRS devices are available, but they are limited by the number of channels (usually having only 8 detectors), which can limit the sensitivity, contrast, and resolution of imaging. High-density imaging can improve sensitivity, contrast, and resolution by providing many measurements and averaging the signals originating from the target cerebral focus area …


Computational Simulation Of A Femoral Nail Fracture, Stephen Charles Whatley Jan 2019

Computational Simulation Of A Femoral Nail Fracture, Stephen Charles Whatley

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Every year in the United States roughly 300,000 people over the age of 65 suffer from a hip fracture. Ninety five percent of which are the result from a fall. The resulting hip fracture can be classified into several categories of fracture. Depending on the damage the patient could be implanted with a femoral nail device to assist in their recovery. These devices can, however, have complications during recovery. In some cases, these nails can have a failure rate as high as 10%. When failure occurs, extensive investigations are needed to determine the causes of failure. These investigations involve physical …


Chondroitin Sulfate Hydrogels For Total Wound Care Devices, Tushar Goswami Jan 2019

Chondroitin Sulfate Hydrogels For Total Wound Care Devices, Tushar Goswami

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Chondroitin sulfate (CS) is a naturally occurring bio-polymer found in areas of high cartilage in mammals. In directed applications, such as hydrogels, CS can be used to impact keratinocyte growth cycles. In this work, CS based hydrogels were utilized to accelerate wound healing and, in conjunction with a graphene sensor, monitor wound fluid pH. The hydrogels were cast onto a graphene field effect transistor (GFET) to obtain the benefits of the hydrogel wound healing capabilities, while also utilizing the pH sensitivity of the graphene. Results showed that the hydrogel caused a fivefold increase in cell size over the course of …


Characterizing Basal-Like Triple Negative Breast Cancer Using Gene Expression Analysis: A Data Mining Approach, Qamar Alsabi Jan 2019

Characterizing Basal-Like Triple Negative Breast Cancer Using Gene Expression Analysis: A Data Mining Approach, Qamar Alsabi

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Triple-negative breast cancer (TNBC) is characterized by the absence of expression of the estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 (HER2). Therefore, TNBC is unresponsive to targeted hormonal therapies, which limits treatment options to nonselective chemotherapeutic agents. Basal-like breast cancers (BLBCs) represent a subset of about 70% of TNBCs, more frequently affecting younger patients, being more prevalent in African-American women and significantly more aggressive than tumors of other molecular subtypes, with high rates of proliferation and extremely poor clinical outcomes. Proper classification of BLBCs using current pathological tools has been a major challenge. Although TNBCs have …


Electroceutical Therapy In Amyotrophic Lateral Sclerosis: A Novel Preliminary Study, Morgan Michelle Highlander Jan 2018

Electroceutical Therapy In Amyotrophic Lateral Sclerosis: A Novel Preliminary Study, Morgan Michelle Highlander

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Amyotrophic Lateral Sclerosis (ALS) is a fatal, neurodegenerative disease that is characterized by the death of motoneurons. Life expectancy is only 3-5 years from diagnosis and current treatments only extend survival by 2-3 months. The mechanism of motoneuron death in ALS is still largely unknown, but abnormal motoneuron excitability has been extensively documented. Because the intrinsic excitability of a motoneuron is a defining measure of its normal function, characterizing and regulating motoneuron excitability has become one of the primary aims of ALS research. Although not previously explored in ALS, other clinical applications show the ability of certain electroceutical techniques to …


Coupling Of Mechanical And Electromagnetic Fields Stimulation For Bone Tissue Engineering, Alyaa I. Aldebs Jan 2018

Coupling Of Mechanical And Electromagnetic Fields Stimulation For Bone Tissue Engineering, Alyaa I. Aldebs

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Alternative bone regeneration strategies that do not rely on harvested tissue or exogenous growth factors and cells are badly needed. However, creating living tissue constructs that are structurally, functionally and mechanically comparable to the natural bone has been a challenge so far. A major hurdle has been recreating the bone tissue microenvironment using the appropriate combination of cells, scaffold and stimulation to direct differentiation. This project presents a bone regeneration formulation that involves the use of human adipose-derived mesenchymal stems cells (hASCs) and a 3D scaffold based on a self-assembled peptide hydrogel doped with superparamagnetic nanoparticles (NPs). Osteogenic differentiation of …


M1 To M2 Macrophage Induction Using Retinoic Acid And Mesenchymal Stem Cells Loaded On An Electrospun Pullulan/Gelatin Scaffold To Promote Healing Of Chronic Wounds, Kaivon Assani Jan 2018

M1 To M2 Macrophage Induction Using Retinoic Acid And Mesenchymal Stem Cells Loaded On An Electrospun Pullulan/Gelatin Scaffold To Promote Healing Of Chronic Wounds, Kaivon Assani

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Modulation of macrophage polarization is required for effective tissue repair and regenerative therapies. Conversion of macrophages from inflammatory M1 to fibrotic M2 phenotype could help in diseases such as chronic wound which are stuck in inflammatory state. During the inflammatory phase, macrophages are of the inflammatory phenotype (M1) and distribute pro-inflammatory cytokines including TNF-a and IL1[beta] which are microbicidal and recruit/activate cells. In normal wound healing macrophages then switch to a fibrotic phenotype (M2) promoting wound closure by angiogenesis, and matrix deposition. Chronic wounds are a major biological and financial burden to both patients and the health care system, costing …


Effect Of Dimensionality On In Vitro Growth Environment And Mesenchymal Stem Cell Function, Fatema Tuj Zohora Jan 2018

Effect Of Dimensionality On In Vitro Growth Environment And Mesenchymal Stem Cell Function, Fatema Tuj Zohora

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The use of the standard two dimensional (2D) cell culture has laid down the fundamentals of molecular and cell biology. However, recent advances in cell-based regenerative medicine raises the concern on deconstructing cellular behaviors in more physiologically relevant three dimensional (3D) microenvironments. Differences in cell response in 2D versus 3D systems arise from the perturbations in gene expression patterns that stem from how cells sense their underlying 2D or surrounding 3D matrices and adjust their phenotypes accordingly. Thus, cells are no longer considered as a solitary entity of genome but a context arises from a combinatorial interactions of cell-ECM, cell-cell, …


Novel Auto-Calibrating Neural Motor Decoder For Robust Prosthetic Control, Andrew Earl Montgomery Jan 2018

Novel Auto-Calibrating Neural Motor Decoder For Robust Prosthetic Control, Andrew Earl Montgomery

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The overarching goal of this project is to develop novel neural motor decoders for prosthetic control. EMG decoders measure the activity from an intact but non-target muscle. Neural motor decoders transform the signal measured from the severed motor axons of the target muscle. A multi-scale, highly-realistic computer model of a spinal motor pool was developed (Allen & Elbasiouny, 2018) to serve as a computational platform for decoder development and testing. A firing rate-based algorithm was developed to transform the aggregate discharge of the motor pool into a command signal to control the simulated prosthetic MuJoCo hand. This algorithm was informed …


Identifying The Impact Of Noise On Anomaly Detection Through Functional Near-Infrared Spectroscopy (Fnirs) And Eye-Tracking, Ryan Dwight Gabbard Jan 2017

Identifying The Impact Of Noise On Anomaly Detection Through Functional Near-Infrared Spectroscopy (Fnirs) And Eye-Tracking, Ryan Dwight Gabbard

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Occupational noise frequently occurs in the work environment in military intelligence, surveillance, and reconnaissance (ISR) operations. This impacts cognitive performance by acting as a stressor, potentially interfering with the analysts' decision making process. In this study the effects of different noise stimuli on analysts' performance and workload in anomaly detection were investigated by simulating a noisy work environment. Functional near infrared spectroscopy (fNIRS) was utilized to quantify oxy-hemoglobin (HbO) and deoxy-hemoglobin (HbD) concentration changes in the prefrontal cortex (PFC), as well as behavioral measures which include eye-tracking, reaction time, and accuracy rate. It was found that HbO for some of …


Low-Cost, Wireless Optical Oximeter For Monitoring Of Brain Function In High-Risk Pediatric Population, Zahra Meghjani Jan 2016

Low-Cost, Wireless Optical Oximeter For Monitoring Of Brain Function In High-Risk Pediatric Population, Zahra Meghjani

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Nearly 4 million neonates die every year due to brain injuries, most caused by hypoxia. Neonatal ICU requires newborns with critical health conditions to be monitored continuously calling for the need of a non-invasive, compact and portable device. However, commercial devices are mostly bulky and/or expensive. The neonatal mortality is higher in under-developed countries, where such expensive and large devices are not affordable. Hence, my thesis focuses on building first generation compact, inexpensive, and wireless device that can monitor and provide feedback to clinicians during intervention. This approach is based on light absorption by oxy- and deoxy-hemoglobin chromophores. The total …


Use Of Eeg To Understand Brain Intensity In Engineering Students Using A Stem Educational Mobile Application, Kevin Hatcher Jan 2016

Use Of Eeg To Understand Brain Intensity In Engineering Students Using A Stem Educational Mobile Application, Kevin Hatcher

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In the first two years of undergraduate work in engineering, students are taught concepts such as physics, electronics, and most importantly calculus. It is especially important for students to get a better grasp on foundational math concepts, such as calculus in the beginning or they will be overwhelmed by the workload to come. The focus of this research was to understand how students learning calculus, could benefit from an augmented-educational mobile application. In the study students were measured with electroencephalography (EEG) measurements utilized by the Emotive EPOC® as they attempted to solve different limit themed problems in order to determine …


Characterization Of Peripheral Lung Lesions By Statistical Image Processing Of Endobronchial Ultrasound Images, Aaron T. Madaris Jan 2016

Characterization Of Peripheral Lung Lesions By Statistical Image Processing Of Endobronchial Ultrasound Images, Aaron T. Madaris

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This thesis introduces the concept of implementing greyscale analysis, also known as intensity analysis, on endobronchial ultrasound (EBUS) images for the purposes of diagnosing peripheral lung tumors. The statistical methodology of using greyscale and histogram analysis allows the characterization of lung tissue in EBUS images. Regions of interest (ROI) will be analyzed in MATLAB and a feature vector will be created. A feature vector of first-order, second-order and histogram greyscale analysis will be created and used for the classification of malignant vs benign peripheral lung tumors. The tools that were implemented were MedCalc for the initial statistical analysis of receiver …


Improving Anomaly Detection Through Identification Of Physiological Signatures Of Unconscious Awareness, Alyssa Marie Piasecki Jan 2016

Improving Anomaly Detection Through Identification Of Physiological Signatures Of Unconscious Awareness, Alyssa Marie Piasecki

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Missed anomalies have the potential to cause detrimental effects in the Intelligence, Surveillance, and Reconnaissance (ISR) domain. One possible cause of these missed anomalies is that cognitive processing may not reach conscious awareness and may only be perceived by the unconscious mind. Identification of correlates of these unconscious processes could provide an insight into potential missed targets. The present study explored missed anomalies in a visual search task and the possibility of unconscious awareness. Eye metrics were recorded and a "Detection Threshold Model" was created and validated with a nominal logistic regression model, in order to characterize the search patterns …


Comparison Of Vascular Pulsatility In The Native Beating Heart Versus Direct Mechanical Ventricular Actuation Support Of The Fibrillating Heart, Nathan Victor Wright Jan 2016

Comparison Of Vascular Pulsatility In The Native Beating Heart Versus Direct Mechanical Ventricular Actuation Support Of The Fibrillating Heart, Nathan Victor Wright

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Most conventional cardiac assist devices today employ continuous flow blood pumps to supplement function in the dysfunctional heart. Continuous flow pumps are predominantly preferred to the original pulsatile pumps due to the smaller size (greater implantability) and higher efficiency they achieve. However, interest in the impact of vascular pulsatility on human health has arisen from the growing evidence of higher complications with nonpulsatile devices compared to pulsatile devices. Direct cardiac compression (DCC) offers a unique solution to the pulsatility issue through the application of force directly to the heart's surface. It is believed that employing the existing pump architecture of …


Design And Evaluation Of A Fiber Optic Shape Tracker For Use As A Navigational Aid In Endovascular Guidewires And Catheters, Benjamin Stewart Rinehart Jan 2016

Design And Evaluation Of A Fiber Optic Shape Tracker For Use As A Navigational Aid In Endovascular Guidewires And Catheters, Benjamin Stewart Rinehart

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Endovascular intervention is the current gold-standard for screening and treating aortic aneurysms and complications caused by peripheral vascular disease (PAD). A typical endovascular procedure begins with inserting an endovascular guidewire into the femoral artery via incision. A catheter is then threaded over the guidewire and both tools are then navigated to the treatment site. The navigation is guided solely by fluoroscopy (x-ray) imagery that is performed throughout the duration of the procedure. Not only does this method provide limited 2-D guidance, but also exposes the patient and medical staff to high levels of radiation. This thesis research focuses on the …