Development Of A Novel Handheld Device For Active Compensation Of Physiological Tremor, Abhijit Saxena

Electronic Thesis and Dissertation Repository

In microsurgery, the human hand imposes certain limitations in accurately positioning the tip of a device such as scalpel. Any errors in the motion of the hand make microsurgical procedures difficult and involuntary motions such as hand tremors can make some procedures significantly difficult to perform. This is particularly true in the case of vitreoretinal microsurgery. The most familiar source of involuntary motion is physiological tremor. Real-time compensation of tremor is, therefore, necessary to assist surgeons to precisely position and manipulate the tool-tip to accurately perform a microsurgery. In this thesis, a novel handheld device (AID) is described for compensation …

Metrics For Evaluating Surgical Microscope Usage During Myringotomy, Arefin M. Shamsil

Electronic Thesis and Dissertation Repository

Abstract

Although teaching and learning surgical microscope manoeuvring is a fundamental step in middle ear surgical training, currently there is no objective method to teach or assess this skill. This thesis presents an experimental study designed to implement and test sets of metrics capable of numerically evaluating microscope manoeuvrability and qualitatively assessing surgical expertise of a subject during a middle ear surgery called myringotomy. The experiment involved performing a myringotomy on a fixed cadaveric ear. As participants, experienced ear-nose-throat (ENT) surgeons and ENT surgical residents were invited. While performing the procedure, their microscope manoeuvring motions were captured as translational and …

Preoperative Planning Of Robotics-Assisted Minimally Invasive Cardiac Surgery Under Uncertainty, Hamidreza Azimian

Electronic Thesis and Dissertation Repository

In this thesis, a computational framework for patient-specific preoperative planning of Robotics-Assisted Minimally Invasive Cardiac Surgery (RAMICS) is developed. It is expected that preoperative planning of RAMICS will improve the rate of success by considering robot kinematics, patient-specific thoracic anatomy, and procedure-specific intraoperative conditions. Given the significant anatomical features localized in the preoperative computed tomography images of a patient's thorax, port locations and robot orientations (with respect to the patient's body coordinate frame) are determined to optimize characteristics such as dexterity, reachability, tool approach angles and maneuverability. In this thesis, two approaches for preoperative planning of RAMICS are proposed that …

Development And Application Of A Portable System To Reliably Measure Grip Forces Using Thin-Film Force Sensors, Shane Vincent Tornifoglio

Master's Theses

Accurate tracking of hand grip force is an important consideration needed for a robust understanding in the study of human biomechanics. One aspect where it proves useful is in hand-arm vibration, such as from gripping a power tool. Depending on how firmly the user is gripping the tool, they may change their exposure levels to the tool vibration, which can lead to potential disorders such as Hand-Arm Vibration Syndrome (HAVS).

A small, battery powered portable force unit has been developed to supply power to, and condition, the signals from eight thin-film force sensors. This gives a better understanding of the …

Robust Dynamic Balance Of Ap-1 Transcription Factors In A Neuronal Gene Regulatory Network., Gregory M Miller, Babatunde A Ogunnaike, James S Schwaber, Rajanikanth Vadigepalli

Rajanikanth Vadigepalli

BACKGROUND: The octapeptide Angiotensin II is a key hormone that acts via its receptor AT1R in the brainstem to modulate the blood pressure control circuits and thus plays a central role in the cardiac and respiratory homeostasis. This modulation occurs via activation of a complex network of signaling proteins and transcription factors, leading to changes in levels of key genes and proteins. AT1R initiated activity in the nucleus tractus solitarius (NTS), which regulates blood pressure, has been the subject of extensive molecular analysis. But the adaptive network interactions in the NTS response to AT1R, plausibly related to the development of …

A Novel Imaging System For Automatic Real-Time 3d Patient-Specific Knee Model Reconstruction Using Ultrasound Rf Data, Rimon Adel Messiha Tadross

Doctoral Dissertations

This dissertation introduces a novel imaging method and system for automatic real-time 3D patient-specific knee model reconstruction using ultrasound RF data. The developed method uses ultrasound to transcutaneously digitize a point cloud representing the bone’s surface. This point cloud is then used to reconstruct 3D bone model using deformable models method.

In this work, three systems were developed for 3D knee bone model reconstruction using ultrasound RF data. The first system uses tracked single-element ultrasound transducer, and was experimented on 12 knee phantoms. An average reconstruction accuracy of 0.98 mm was obtained. The second system was developed using an ultrasound …

Development And Experimental Analysis Of Wireless High Accuracy Ultra-Wideband Localization Systems For Indoor Medical Applications, Michael Joseph Kuhn

Doctoral Dissertations

This dissertation addresses several interesting and relevant problems in the field of wireless technologies applied to medical applications and specifically problems related to ultra-wideband high accuracy localization for use in the operating room. This research is cross disciplinary in nature and fundamentally builds upon microwave engineering, software engineering, systems engineering, and biomedical engineering. A good portion of this work has been published in peer reviewed microwave engineering and biomedical engineering conferences and journals. Wireless technologies in medicine are discussed with focus on ultra-wideband positioning in orthopedic surgical navigation. Characterization of the operating room as a medium for ultra-wideband signal transmission …

Modeling Cardiac Muscle Mechanics, Lorenzo Sewanan

Senior Theses and Projects

The heart is a complex electro-mechanical system which is intrinsically and intimately linked to physiology and pathology. Cardiac muscle tissue underlies the dynamics of the heart; understanding cardiac muscle tissue allows insight into the working of the heart at a fundamental level. Indeed, models allow a theoretical understanding of systems which necessarily exceeds that of experiment. Here, we describe a novel mathematical model of cardiac muscle mechanics based on functional relations.

Noninvasive Assessment And Modeling Of Diabetic Cardiovascular Autonomic Neuropathy, Siqi Wang

Theses and Dissertations--Biomedical Engineering

Noninvasive assessment of diabetic cardiovascular autonomic neuropathy (AN): Cardiac and vascular dysfunctions resulting from AN are complications of diabetes, often undiagnosed. Our objectives were to: 1) determine sympathetic and parasympathetic components of compromised blood pressure regulation in patients with polyneuropathy, and 2) rank noninvasive indexes for their sensitivity in diagnosing AN. Continuous 12-lead electrocardiography (ECG), blood pressure (BP), respiration, regional blood flow and bio-impedance were recorded from 12 able-bodied subjects (AB), 7 diabetics without (D0), 7 with possible (D1) and 8 with definite polyneuropathy (D2), during 10 minutes supine control, 30 minutes 70-degree head-up tilt and 5 minutes supine recovery. …

An Investigation Of Reflective Mulches For Use Over Capillary Mat Systems For Winter-Time Greenhouse Strawberry Production, George E. Meyer, Ellen T. Paparozzi, Elizabeth Walter-Shea, Erin E. Blankenship, Stacy A. Adams

Department of Agronomy and Horticulture: Faculty Publications

Photosynthethically active radiation (PAR) is a principle environmental variable used by horticultural specialists, agronomists and ecosystem modelers to characterize the quantity and quality of light conducive to plant growth and development. Spatial distribution of PAR in a greenhouse can be quite variable and diffuse throughout the day time photoperiod, especially at low sun angles in northern regions of the United States. Four colors of reflective plastic mulches (white, red, olive, and black) were evaluated for winter-time strawberry (Fragaria × ananassa Duch.) production based on their reflectance and transmittance properties in a double-polyethylene, plastic-glazed Quonset greenhouse inNebraska. The spectral properties …