Biomedical Engineering and Bioengineering Commons^™

Calibration And Validation Of An In Vitro Ultrasound Device To Deliver Targeted Thermal Enhancement Of Hmsc Osteogenesis, Dionne Dawkins

Dissertations and Theses

Osteoarthritis (OA) is a disease that affects millions of people annually, often the elderly, and limits their physical abilities. Current methods of treating OA are often very invasive, and expensive, costing the Medicare system billions of dollars annually. A minimally invasive therapy that can be localized to the affected area that provides both relief and a short recovery time is optimal for treating the disease. For targeted therapy and clinical use, therapeutic ultrasound in the 0.7 MHz to 3 MHz frequency range can provide relief and is convenient, portable and localized. Low-intensity pulsed ultrasound (LIPUS) has been proven in clinical …

Development Of A Cell Morphological Analysis Tool To Evaluate The Ultrasound Vibrational Effects On Cell Adhesion, Joseph M. Smith

Dissertations, Master's Theses and Master's Reports - Open

Fibroblast encapsulation is a stage of the wound healing process in which the implanted device is separated from the biological environment due to the formation of fibrotic tissue. Uncontrolled adhesion of fibroblasts, called fibrosis, has the ability to inhibit an implanted device’s functionality over its lifetime. Over time, fibroblasts have been shown to cause loosening and failure of bone-anchor implants which could include the possibility of harming the patient. The encapsulating process could also hinder the sensitivity of implanted biosensors operating in the body for continuous monitoring. Unfortunately, the antifouling surfaces which are commonly used on implanted devices to control …

Real-Time Temperature Imaging Using Ultrasonic Change In Backscattered Energy, Weiyuan Zhao

McKelvey School of Engineering Graduate Student Theses & Dissertations

Thermal therapy from low-temperature cryosurgery to high-temperature ablation of tumors and unwanted electrical pathways has gained increased attention. Temperature imaging (TI) from magnetic resonance studies is the de facto standard for volumetric estimation of temperature. Ultrasound has the advantages of being cheap, portable, non-invasive and non-ionizing. Our group showed in predictions for single scatterers, simulations of scatterer populations and measurements in 1D, 2D and 3D, that CBE changed monotonically with temperature with 1^oC accuracy. An obstacle to clinical application of CBE TI is estimation of temperature in real time, which is limited by time for motion compensation (MC). …

In Vivo Flow Measurements Of Murine Renal Arteries And Veins With High Frequency Ultrasound, Amy E. Bogucki, Hilary D. Schroeder, Alexa A. Yrineo, Craig J. Goergen

The Summer Undergraduate Research Fellowship (SURF) Symposium

The number of glomeruli in the kidneys has been shown to have an effect on the decline in renal function over time (Brenner, Garcia, Anderson 1988). Furthermore, flow in the renal arteries and veins may depend on the number of glomeruli in the kidney. Consistent in vivo measurements of volumetric flow in the renal arteries and veins are difficult to obtain. Thus, the purpose of this study was to develop non-invasive imaging techniques capable of estimating arterial and venous flow to kidneys. A high-frequency small animal ultrasound system was chosen based upon its excellent spatial and temporal resolution when imaging …

Visualization Of Complex Flow Patterns In Angiotensin Ii-Induced Dissecting Murine Abdominal Aortic Aneurysms With High Frequency Ultrasound, Hilary D. Schroeder, Alexa A. Yrineo, Amy E. Bogucki, Craig J. Goergen

The Summer Undergraduate Research Fellowship (SURF) Symposium

Abdominal aortic aneurysm (AAA) rupture is a common cause of mortality in the United States. Current treatments are only employed once the risk of rupture outweighs the risks associated with surgery. Murine models have been developed to characterize AAA pathogenesis in the hope that new treatments will be developed. For this study, angiotensin II (AngII) was infused subcutaneously into apolipoprotein E-deficient (ApoE^-/-) mice using an osmotic mini-pump over 28 days. ApoE^-/- mice (16-week-old, 3 females, 2 males) were imaged using a VisualSonics Vevo 2100 high frequency ultrasound before pump implantation and 3, 7, 14, 21, and 27 …

Development Of Non-Invasive In Vivo Ultrasound Imaging Techniques For Elastase-Induced Experimental Abdominal Aortic Aneurysms, Alexa A. Yrineo, Elizabeth A. Nunamaker, Hilary D. Schroeder, Amy E. Bogucki, Craig J. Goergen

The Summer Undergraduate Research Fellowship (SURF) Symposium

Abdominal aortic aneurysms (AAAs) are pathological dilations of the aorta which are associated with significant morbidity and mortality. The underlying mechanisms that cause this inflammatory disease are not fully understood and thus, are currently under investigation. In the hopes of preventing disease progression, rodent models that mimic the human condition have been developed to provide insight into the pathogenesis of AAAs. In this study, porcine pancreatic elastase (0.44 U; Sigma-Aldrich) was infused into the infrarenal aortas of male, Sprague Dawley rats to induce aneurysms. To perform the surgery, temporary ligatures were placed around proximal and distal sections of the abdominal …

Biomedical Photoacoustic Imaging Using Gas-Coupled Laser Acoustic Detection, Jami L. 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 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. Here, we report the use of a noncontact photoacoustic and laser-ultrasound 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 composite material evaluation. This technique has the potential …

Phase Transitions Of Nanoemulsions Using Ultrasound: Experimental Observations, Ram Singh, Ghaleb A. Husseini, William G. Pitt

Faculty Publications

The ultrasound-induced transformation of perfluorocarbon liquids to gases is of interest in the area of drug and gene delivery. In this study, three independent parameters (temperature, size, and perfluorocarbon species) were selected to investigate the effects of 476-kHz and 20-kHz ultrasound on nanoemulsion phase transition. Two levels of each factor (low and high) were considered at each frequency. The acoustic intensities at gas bubble formation and at the onset of inertial cavitation were recorded and subsequently correlated with the acoustic parameters. Experimental data showed that low frequencies are more effective in forming and collapsing a bubble. Additionally, as the size …

Propagation Of Ultrasound Through Freshly Excised Human Calvarium, Armando Garcia Noguera

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

The propagation of ultrasound through complex biological media, such as the human calvarium, poses a great challenge for modern medicine. Several ultrasonic techniques commonly used for treatment and diagnosis in most of the human body are still difficult to apply to the human brain, in part, because of the properties of the skull. Moreover, an understanding of the biomechanics of transcranial ultrasound may provide needed insight into the problem of blast wave induced traumatic brain injury (TBI). In the present study, the spatial variability of ultrasonic properties was evaluated for relevant frequencies of 0.5, 1, and 2.25 MHz. A total …

Increased Susceptibility Of Arterial Tissue To Wire Perforation With The Application Of High Frequency Mechanical Vibrations, Mark Wylie, Garrett Mcguinness, Graham Gavin

Articles

High frequency mechanical vibrations (20–50 kHz), delivered via small diameter flexible wire waveguides represent a minimally invasive technology for the treatment of chronic total occlusions (CTOs) and in other tissue ablation applications. Tissue disruption is reported to be caused by repetitive mechanical contact and cavitation. This work focuses on the effects of vibrating wire waveguides in contact with arterial tissue. An apparatus with clinically relevant parameters was used, characterized as operating at 22.5 kHz and delivering amplitudes of vibration of 17.8 - 34.3 µm (acoustic intensity, I_SATA: 1.03 - 3.83 W/cm²) via 1.0 mm diameter waveguides. …

Characterization And Implementation Of Low Intensity Pulsed Ultrasound As A Tool To Apply Physical Load To Scaffolds And Bone Cells For Fracture Repair, Scott Frazee

Master's Theses

One current challenge in treating bone fractures is the effective treatment of non-unions and delayed unions. Low Intensity Pulsed Ultrasound (LIPUS) has been approved by the FDA to treat fresh fractures since 1994 and non-unions since 2000 and is an attractive treatment option because it is non-invasive. The mechanism by which it works, however, is not well understood; what is known is largely confined to the resultant changes in chemical output of cells. In this thesis several concepts and techniques were brought together to investigate the following hypothesis: LIPUS produces a measurable physical load that results in measurable deformation and …

High Power, Low Frequency Ultrasound: Meniscal Tissue Interaction And Ablation Characteristics, Brendan O'Daly, Edmund Morris, Graham Gavin, Conor Keane, John O Byrne, Garrett Mcguinness

Articles

Abstract—This study evaluates high power low frequency ultrasound transmitted via a flat vibrating probe tip as an alternative technology for meniscal debridement in the bovine knee. An experimental force controlled testing rig was constructed using a 20 kHz ultrasonic probe suspended vertically from a load cell. Effect of variation in amplitude of distal tip displacement (242–494 mm peak-peak) settings and force (2.5–4.5 N) on tissue removal rate (TRR) and penetration rate (PR) for 52 bovine meniscus samples was analyzed. Temperature elevation in residual meniscus was measured by embedded thermocouples and histologic analysis. As amplitude or force increases, there is a …

Ultrasound Echo Is Related To Stress And Strain In Tendon, Sarah Duenwald, Hirohito Kobayashi, Kayt E. Frisch, Roderic Lakes, Ray Vanderby Jr.

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

The mechanical behavior of tendons has been well studied in vitro. A noninvasive method to acquire mechanical data would be highly beneficial. Elastography has been a promising method of gathering in vivo tissue mechanical behavior, but it has inherent limitations. This study presents acoustoelasticity as an alternative ultrasound-based method of measuring tendon stress and strain by reporting a relationship between ultrasonic echo intensity (B-mode ultrasound image brightness) and mechanical behavior of tendon in vitro. Porcine digital flexor tendons were cyclically loaded in a mechanical testing system while an ultrasonic echo response was recorded. We report that echo intensity …

Perforation Of Arterial Tissue Using Kilohertz Frequency Ultrasound Delivered Via Wire Waveguides, Mark Wylie, Garrett Mcguinness, Graham Gavin

Conference Papers

An emerging technology proposes the use of low frequency-high power ultrasound transmitted via wire waveguides for the disruption and ablation of atherosclerotic lesions, more specifically advanced fibrous or calcified plaques such as chronic total occlusions (CTO). This energy delivery selectively ablates rigid diseased tissue by means of direct mechanical contact, cavitation and other forces generated by the intense dynamic pressure fields generated.

The first clinical device using this energy delivery was granted FDA approval in 2007 [1] for the ablation of CTOs and most research to date has focused on ablation and disruption of hard, fibrous or calcified tissues [2]. …

Ultrasound Transient Shear Wave Elasticity Imaging For Tendon Tissue, Pengfei Song

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Degeneration of tendon tissue is a common cause of tendon dysfunction with the symptoms of repeated episodes of pain and palpable increase of tendon thickness. Tendon mechanical properties are directly related to its physiological composition and the structural organization of the interior collagen fibers which could be altered by tendon degeneration due to overuse or injury. Thus, measuring mechanical properties of tendon tissue may represent a quantitative measurement of pain, reduced function, and tissue health. Ultrasound elasticity imaging has been developed in the last two decades and has proved to be a promising tool for tissue elasticity imaging. To date, …

A Linear Finite Element Acoustic Fluid-Structure Model Of Ultrasonic Angioplasty In Vivo, Mark Wylie, Garrett Mcguinness, Graham Gavin

Articles

The delivery of high-power ultrasonic energy via small diameter wire waveguides represents a new alternative therapy for the treatment of chronic totally occluded arteries (CTOs). This type of energy manifests itself as a mechanical vibration at the distal-tip of the waveguide with amplitudes of vibration up to 60 µm and at frequencies of 20- 50 kHz. Disruption of diseased tissue is reported to be a result of direct mechanical ablation, cavitation, pressure components and acoustic streaming and that ablation was only evident above the cavitation threshold. This work presents a linear finite element acoustic fluid-structure model of an ultrasonic angioplasty …

Dual-Stage Sugar Substitution In Strawberries With A Stevia-Based Sweetener, Juan Garcia-Noguera, Curtis L. Weller, Francisca I. P. Oliveira, Sueli Rodrigues, Fabiano A. N. Fernandes

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The present study introduces and analyzes a new process denominated dual-stage sugar substitution (D3S). This process aims to induce sugar substitution in strawberries. In a first stage, high-calorie sugars (sucrose, fructose and glucose) are partially removed from the fruit samples and in a second stage, low-calorie sugar (stevioside and rebaudioside) is incorporated to the fruit to maintain its sweetness. The process was evaluated by studying the use of ultrasound application in one or both stages of the D3S process. Best performance of the process was obtained by subjecting the fruit samples to ultrasound in the sugar removal stage followed by …

Ultrasound-Assisted Osmotic Dehydration Of Strawberries: Effect Of Pretreatment Time And Ultrasonic Frequency, Juan Garcia-Noguera, Francisca I. P. Oliveira, Maria Izabel Gallão, Curtis L. Weller, Sueli Rodrigues, Fabiano A. N. Fernandes

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Pretreatment of fruits prior to drying has shown success in reducing drying time and costs. In this work, ultrasound-assisted osmotic dehydration has been implemented as a method to increase water diffusivity and reduce drying time in strawberries. Strawberry halves were immersed in distilled water and in two different concentrations of sucrose solutions while pretreatment time and ultrasonic frequency levels were varied to determine their effect on drying time, water loss, and soluble solids gain. A microscopic analysis was carried out to evaluate the formation of microchannels and other changes to the fruit tissue structure. Greater sucrose concentration used in ultrasound- …

Sequestration And Ultrasound-Induced Release Of Doxorubicin From Stabilized Pluronic P105 Micelles, John D. Pruitt, William G. Pitt

Faculty Publications

Controlled drug delivery from micelles requires that the micelles remain stable when diluted below their critical micelle concentration, such as upon injection into blood. A cross-linked, interpenetrating network of N,N-diethylacrylamide (NNDEA) was polymerized in the core of Pluronic P105 micelles to stabilize temporarily the micelles at concentrations below the critical micellar concentration of free P105. The stabilized Pluronic micelles (called Plurogels) were able to sequester the drug doxorubicin (Dox) and protect HL-60 cells from the drug at concentrations where non-stabilized Pluronic provided no protection. The protection lasted ~ 12 hr, which is similar to the half-life of the particles. Application …

High-Power Low-Frequency Ultrasound: A Review Of Tissue Dissection And Ablation In Medicine And Surgery, Brendan O'Daly, Edmund Morris, Graham Gavin, John O'Byrne, Garrett Mcguinness

Articles

High-power low-frequency ultrasound in the range 20–60 kHz has wide ranging clinical applications in surgical and medical instruments for biological tissue cutting, ablation or fragmentation, and removal. Despite widespread clinical application and common device operating characteristics, there is an incomplete understanding of the mechanism of tissue failure, removal and damage. The relative contribution of cavitation, direct mechanical impact and thermal effects to each process for specific tissue types remains unclear. Different and distinct mechanisms and rates of tissue removal are observed for interaction with soft and hard tissue types. Device operating parameters known to affect the interaction include frequency, peak–peak …

Experimental And Numerical Investigation Of Wire Waveguides For Therapeutic Ultrasound Angioplasty, Declan Noone (Thesis)

Other resources

Therapeutic ultrasound angioplasty is an emerging minimally invasive cardiovascular procedure for disrupting atherosclerotic lesions using small diameter wire waveguides. The lesions are damaged through a combination of direct ablation, pressure waves, cavitation and acoustic streaming caused by distal-tip displacements at ultrasonic frequencies. Numerical and experimental methods are used to investigate the outputs of the wire waveguides during ultrasonic activation. A commercially available generator and acoustic horn are used in combination with Nickel-Titanium (NiTi) wire waveguides in this study. A laser sensor is used to measure the frequency and amplitude output of the distal tip of the wire waveguide, and this …

A Coupled Fluid-Structure Model Of A Therapeutic Ultrasound Angioplasty Wire Waveguide, Graham Gavin, Finbar Dolan, M.S. Hashmi, Garrett Mcguinness

Articles

Ultrasonic longitudinal displacements, delivered to the distal tips of small diameter wire waveguides, have been shown to be capable of disrupting complicated atherosclerotic plaques during vascular interventions. These ultrasonic displacements can disrupt plaques by direct contact ablation but also by pressure waves, associated cavitation and acoustic streaming developed in the surrounding blood and tissue cavities. The pressure waves developed within the arterial lumen appear to play a major role but are complex to predict as they are determined by the distal tip output of the wire waveguide (both displacement and frequency), the geometric features of the waveguide tip and the …

Performance Characteristics Of A Therapeutic Ultrasound Wire Waveguide, Graham Gavin, Garrett Mcguinness, Finbar Dolan, M.S. Hashmi

Articles

Therapeutic ultrasound angioplasty has been investigated, clinically, by a number of researchers and represents a potentially promising therapy for the treatment of atherosclerotic lesions. To date, there has been no detailed analysis of the effect of mechanical design parameters, such as wire geometry or damping characteristics, on wire waveguide performance. An apparatus capable of delivering therapeutic ultrasound down small diameter nickel–titanium (NiTi) wire waveguides is described. The output peak-to-peak (p–p) displacements at the distal tip of a 1.0mm diameter waveguide were measured experimentally, by means of an optical microscope and image analysis software. The output was measured for a range …

Non-Invasive Monitoring Of Bone Health Using Ultrasound, Nashit Jahan Meem

Theses

Bone fractures are estimated to afflict everyone at least once in his/her lifetime. Monitoring this becomes crucial especially when it comes to athletes in order for them to safely resume their regular activities as soon as possible. Technologies currently employed are either very expensive or use harmful radiation.

Ultrasound can monitor bone fractures in a non-invasive manner, as discussed in United States Patent # 5143069. Three transducers are mounted over the test specimen. A pulse generator excites the transmitting receiver. The second receiver is mounted next to the transmitter and acts as a reference receiver that displays the response across …

Robot Assisted Ultrasound Imaged Guided Interstitial Lung Brachytherapy In A Porcine Model, Richard A. Malthaner, Edward Yu, Jerry J. Battista, Chris Blake, Donal Downey, Aaron Fenster

Oncology Presentations

We set out to see if permanent interstitial brachytherapy seeds could be safely and reproducibly inserted thoracoscopicaly with the ZEUS Robotic system and intraoperative ultrasound into in-vivo porcine lungs.

An Acoustic Fluid-Structure Simulation Of A Theraputic Ultrasound Wire Waveguide Apparatus, Graham Gavin, M.S. Hashmi, Finbar Dolan, Garrett Mcguinness

Conference Papers

The use of high-power low-frequency ultrasound transmitted down small diameter wire waveguides is an emerging technology that may have potential in the treatment of complicated atherosclerotic plaques in cardiovascular surgery. This form of energy delivery results in vibrating the distal-tip of the wire waveguide disrupting material by means of direct contact ablation and also cavitation, pressure waves and acoustic streaming in the surrounding fluid. This work describes a numerical acoustic fluid-structure model of the ultrasound wire waveguide and blood surrounding the distal tip. The structural analysis of the model predicts the natural frequencies of the waveguide and shows the extent …

Attenuation And Speed Of 10 Mhz Ultrasound In Canine Blood Of Various Packed Cell Volumes At 37c, D J. Hughes, L A. Geddes, Charles F. Babbs, J D. Bourland, V L. Newhouse

Weldon School of Biomedical Engineering Faculty Publications

The attenuation coefficient and the speed of 10 MHz ultrasound were determined in canine blood at 37 oC by a differential path length technique. Blood specimens with packed cell volumes (PCV) ranging from 0 to 53% were prepared by separating the cells from the plasma and mixing the two components. The mean attenuation coefficient increased linearly with packed cell volume, the least squares regression function being  (dB/cm) = 0.992 +0.039 PCV with a standard error of the estimate = 0.255. The speed of 10 MHz ultrasound, c, in millimetres per second, increased with packed cell volume, the regression function …