Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 10 of 10

Full-Text Articles in Analytical, Diagnostic and Therapeutic Techniques and Equipment

Modeling Of Patient-Specific Periaortic Mechanics And Pulmonary Artery Hemodynamics Based On Phase-Contrast Magnetic Resonance Imaging Sequences., Johane H. Bracamonte Jan 2022

Modeling Of Patient-Specific Periaortic Mechanics And Pulmonary Artery Hemodynamics Based On Phase-Contrast Magnetic Resonance Imaging Sequences., Johane H. Bracamonte

Theses and Dissertations

Inverse modeling in cardiovascular medicine is a collection of methodologies that can provide non-invasive patient-specific estimations of clinical risk factors using medical imaging as inputs. Its incorporation into clinical practice has the potential to improve diagnosis and treatment planning with low associated risks and costs.

Herein, three different phase contrast magnetic resonance imaging (MRI) modalities were implemented as input data, displacement encoding with stimulated echoes (DENSE MRI) applied, and time-resolved velocity encoding phase-contrast MRI, in 1D and 3D, applied to pulmonary artery (PA) hemodynamics.

A model to account for the effect of periaortic interactions due to static and dynamic structures …


Theta Burst Brain Stimulation In Painful Diabetic Neuropathy Patients: Investigating Neural Mechanisms, Bhushan Thakkar Jan 2022

Theta Burst Brain Stimulation In Painful Diabetic Neuropathy Patients: Investigating Neural Mechanisms, Bhushan Thakkar

Theses and Dissertations

Chronic pain (CP) is a significant contributor to disability and disease burden globally. In 2019, approximately 50.2 million adults (20.4% of the US population) experienced chronic pain, contributing to $560-635 billion in direct medical costs. In addition, the worldwide prevalence of diabetes mellitus has reached epidemic proportions and is set to increase to 629 million by 2045. Almost 50% of patients with diabetes present with diabetic neuropathy (DN), and one in five patients with diabetes presents with painful DN (pDN) which is the most common cause of neuropathic pain (NP) in the US. Symptomatic treatment is the mainstay of management …


A Deep Learning U-Net For Detecting And Segmenting Liver Tumors, Vidhya Cardozo Jan 2021

A Deep Learning U-Net For Detecting And Segmenting Liver Tumors, Vidhya Cardozo

Theses and Dissertations

Visualization of liver tumors on simulation CT scans is challenging even with contrast-enhancement, due to the sensitivity of the contrast enhancement to the timing of the CT acquisition. Image registration to magnetic resonance imaging (MRI) can be helpful for delineation, but differences in patient position, liver shape and volume, and the lack of anatomical landmarks between the two image sets makes the task difficult. This study develops a U-Net based neural network for automated liver and tumor segmentation for purposes of radiotherapy treatment planning. Non-contrast simulation based abdominal CT axial scans of 52 patients with primary liver tumors were utilized. …


Strengthening Mental Health Diagnostic Detection In Integrated Primary Care, Julia Brechbiel Jan 2021

Strengthening Mental Health Diagnostic Detection In Integrated Primary Care, Julia Brechbiel

Theses and Dissertations

Primary care behavioral health (PCBH) is crucial for providing mental health treatment to underserved, minority, and uninsured populations. There is a lack of knowledge about accurate mental health diagnoses at PCBH. Underdetection of mental health symptoms has the potential to worsen racial and socioeconomic disparities. Using an expert review process, I developed an abbreviated diagnostic clinical interview (ADCI) for integrated primary care. Next, patients (N = 82) completed the interview after attending PCBH appointments. According to the interview, 63.4% of participants met criteria for a diagnosis, while 64.7% received a diagnosis from their provider. A large portion of patients …


Nebulizer-Based Systems To Improve Pharmaceutical Aerosol Delivery To The Lungs, Benjamin M. Spence Jan 2021

Nebulizer-Based Systems To Improve Pharmaceutical Aerosol Delivery To The Lungs, Benjamin M. Spence

Theses and Dissertations

Combining vibrating mesh nebulizers with additional new technologies leads to substantial improvements in pharmaceutical aerosol delivery to the lungs across therapeutic administration methods. In this dissertation, streamlined components, aerosol administration synchronization, and/or Excipient Enhanced Growth (EEG) technologies were utilized to develop and test several novel devices and aerosol delivery systems. The first focus of this work was to improve the poor delivery efficiency, e.g., 3.6% of nominal dose (Dugernier et al. 2017), of aerosolized medication administration to adult human subjects concurrent with high flow nasal cannula (HFNC) therapy, a form of continuous-flow non-invasive ventilation (NIV). The developed Low-Volume Mixer-Heater (LVMH) …


Development Of A Torque-Based Device For The Quantification Of Arm Rigidity In Patients With Parkinson’S Disease, Georgina O. Miller Jan 2020

Development Of A Torque-Based Device For The Quantification Of Arm Rigidity In Patients With Parkinson’S Disease, Georgina O. Miller

Theses and Dissertations

Parkinsonian rigidity is caused by the inability of the muscles to relax and extend properly, due to reduced dopamine levels and often begins on one side of the body before spreading contralaterally. The current standard for determining joint rigidity in a clinical setting is a test completed by the clinician based on the feel of the relaxed wrist and elbow joints as they are passively flexed and extended and a series of ordinal rating scales, the Movement Disorder Society’s – Unified Parkinson’s Disease Rating Scale (MDS-UPDRS), Hoehn and Yahr Scale (H&Y), and Parkinson’s Disease Questionnaire-39 (PDQ-39). These methods are used …


Motion-Induced Artifact Mitigation And Image Enhancement Strategies For Four-Dimensional Fan-Beam And Cone-Beam Computed Tomography, Matthew J. Riblett Jan 2018

Motion-Induced Artifact Mitigation And Image Enhancement Strategies For Four-Dimensional Fan-Beam And Cone-Beam Computed Tomography, Matthew J. Riblett

Theses and Dissertations

Four dimensional imaging has become part of the standard of care for diagnosing and treating non-small cell lung cancer. In radiotherapy applications 4D fan-beam computed tomography (4D-CT) and 4D cone-beam computed tomography (4D-CBCT) are two advanced imaging modalities that afford clinical practitioners knowledge of the underlying kinematics and structural dynamics of diseased tissues and provide insight into the effects of regular organ motion and the nature of tissue deformation over time. While these imaging techniques can facilitate the use of more targeted radiotherapies, issues surrounding image quality and accuracy currently limit the utility of these images clinically.

The purpose of …


Evaluation And Adaptation Of Live-Cell Interferometry For Applications In Basic, Translational, And Clinical Research, Kevin A. Leslie Jan 2018

Evaluation And Adaptation Of Live-Cell Interferometry For Applications In Basic, Translational, And Clinical Research, Kevin A. Leslie

Theses and Dissertations

Cell mass is an important indicator of cell health and status. A diverse set of techniques have been developed to precisely measure the masses of single cells, with varying degrees of technical complexity and throughput. Here, the development of a non-invasive, label-free optical technique, termed Live-Cell Interferometry (LCI), is described. Several applications are presented, including an evaluation of LCI’s utility for assessing drug response heterogeneity in patient-derived melanoma lines and the measurement of CD3+ T cell kinetics during hematopoietic stem cell transplantation. The characterization of mast cells during degranulation, the measurement of viral reactivation kinetics in Kaposi’s Sarcoma, and drug …


Thyroid Hormone As A Method Of Reducing Damage To Donor Hearts After Circulatory Arrest, William P. Adams Jan 2017

Thyroid Hormone As A Method Of Reducing Damage To Donor Hearts After Circulatory Arrest, William P. Adams

Theses and Dissertations

There is a chronic lack of donor hearts to meet the need for heart transplant both in the US and worldwide. Further, the use of available hearts is limited by the short period between collection and implantation during which the heart can be safely preserved ex vivo. Using mid-thermic Langendorff machine perfusion, we have been able to preserve the metabolic function of a healthy heart for up to 8 hours, twice the limit for current static cold storage. We have also been able to preserve the metabolic function of a damaged DCD Heart collected 30 minutes after cardiac arrest …


Perception Of Differences In Lip Profile Between 2-D And 3-D, Andrew Hansen Jan 2016

Perception Of Differences In Lip Profile Between 2-D And 3-D, Andrew Hansen

Theses and Dissertations

Past studies evaluating the esthetics of orthodontic treatment have been done using 2-D images. New 3-D imaging offers an improved, real-life representation of a subject. The purpose of this study was to determine how laypeople perceived differences in lip position (flat versus ideal lip fullness) in 2-D compared to 3-D.

3dMD images of 8 Caucasian subjects were adjusted to an ideal and flat lip position in 3-D and then in 2-D from the profile view. 2 surveys were created with paired ideal and flat images on the screen, either in 2-D or 3-D, and evaluators were asked to choose which …