Scholars@Duke
David Bradway

David Bradway

Research Scientist, Senior
Biomedical Engineering
david.bradway@duke.edu
Room 1427, Fitzpatrick CIEMAS, 101 Science Dr., Box 90281, Durham, NC 27708-0281
100 Science Drive, Durham, NC 27708
Office hours Hudson Annex 259  

Selected Publications

Volumetric Mechanical Characterization of in vivo Skeletal Muscle Assessed with 3D-Rotational Shear Wave Elasticity Imaging (3D-RSWEI)

Conference IEEE International Ultrasonics Symposium Ius · January 1, 2025 We present a volumetric characterization method for 3D-RSWEI data in in vivo skeletal muscle, in which shear wave speeds (SWS) are quantified at multiple rotational angles through multiple axial depths within the depth-of-field. We have shown in the vastus ... Full text Cite

In Vivo Demonstration of a Real-Time Temporal SNR Acoustic Output Adjustment Method.

Journal Article IEEE Trans Ultrason Ferroelectr Freq Control · August 2024 This work proposes a novel method of temporal signal-to-noise ratio (SNR)-guided adaptive acoustic output adjustment and demonstrates this approach during in vivo fetal imaging. Acoustic output adjustment is currently the responsibility of sonographers, bu ... Full text Link to item Cite

Characterization of Anisotropic Lattice Structured Phantoms Using 3D-Rotational Shear Wave Elasticity Imaging (3D-RSWEI)

Conference IEEE Ultrasonics Ferroelectrics and Frequency Control Joint Symposium Uffc Js 2024 Proceedings · January 1, 2024 We present a 3D-RSWEI characterization of anisotropic lattice phantoms. Shear wave speeds versus rotational angle were measured while the lattices were submerged in water and after embedding in a softer, isotropic polyvinyl alcohol cryogel. In both cases, ... Full text Cite

Evaluation of Myocardial Stiffness in Cardiac Amyloidosis Using Acoustic Radiation Force Impulse and Natural Shear Wave Imaging.

Journal Article Ultrasound Med Biol · August 2023 OBJECTIVE: Increased myocardial stiffness (MS) is an important hallmark of cardiac amyloidosis (CA) caused by myocardial amyloid deposition. Standard echocardiography metrics assess MS indirectly via downstream effects of cardiac stiffening. The ultrasound ... Full text Link to item Cite

Spatial Coherence Adaptive Clutter Filtering in Color Flow Imaging-Part I: Simulation Studies.

Journal Article IEEE open journal of ultrasonics, ferroelectrics, and frequency control · January 2022 The appropriate selection of a clutter filter is critical for ensuring the accuracy of velocity estimates in ultrasound color flow imaging. Given the complex spatio-temporal dynamics of flow signal and clutter, however, the manual selection of filters can ... Full text Cite

Spatial Coherence Adaptive Clutter Filtering in Color Flow Imaging-Part II: Phantom and In Vivo Experiments.

Journal Article IEEE open journal of ultrasonics, ferroelectrics, and frequency control · January 2022 Conventional color flow processing is associated with a high degree of operator dependence, often requiring the careful tuning of clutter filters and priority encoding to optimize the display and accuracy of color flow images. In a companion paper, we intr ... Full text Cite

Mechanisms affecting ALARA MI selected in adaptive ultrasound imaging

Conference IEEE International Ultrasonics Symposium Ius · January 1, 2021 Adaptive acoustic output selection in ultrasound imaging promises to improve adherence to the ALARA (as low as reasonably achievable) principle. Demonstrated imaging sequences have balanced image quality and safety considerations based on transducer channe ... Full text Cite

An Automated ALARA Method for Ultrasound: An Obstetric Ultrasound Feasibility Study.

Journal Article J Ultrasound Med · December 2, 2020 OBJECTIVES: Ultrasound users are advised to observe the ALARA (as low as reasonably achievable) principle, but studies have shown that most do not monitor acoustic output metrics. We developed an adaptive ultrasound method that could suggest acoustic outpu ... Full text Link to item Cite

Force-Map Normalization for ARFI Imaging

Conference IEEE International Ultrasonics Symposium Ius · October 1, 2019 Acoustic Radiation Force Impulse (ARFI) images are used to visualize spatial variations in soft tissue elasticity by showing the displacement of each pixel in response to an applied radiation force. However, accommodations for spatial variations in the app ... Full text Cite

Implementation and Clinical Evaluation of a Fetal ALARA Ultrasound System

Conference IEEE International Ultrasonics Symposium Ius · December 17, 2018 The US Food and Drug Administration (FDA) provides guidelines for acoustic output to ensure that ultrasound remains a safe imaging modality used widely in applications such as obstetrics. However, even within these limits, additional acoustic output that d ... Full text Cite

Clinical Utility of Fetal Short-Lag Spatial Coherence Imaging.

Journal Article Ultrasound Med Biol · April 2018 In this study, we evaluate the clinical utility of fetal short-lag spatial coherence (SLSC) imaging. Previous work has documented significant improvements in image quality with fetal SLSC imaging as quantified by measurements of contrast and contrast-to-no ... Full text Link to item Cite

The Ultrasound File Format (UFF) - First Draft

Conference IEEE International Ultrasonics Symposium Ius · January 1, 2018 The lack of a standard format for storing ultrasound research data is hindering our ability to share and compare research results. This is slowing down the progress in our field, making it difficult to assess the relevance of new techniques. In October 201 ... Full text Cite

Notice of Removal: Translation of fetal short-lag spatial coherence (SLSC) imaging into clinical practice: A pilot study

Conference IEEE International Ultrasonics Symposium Ius · October 31, 2017 Fetal short-lag spatial coherence (SLSC) imaging has demonstrated 64-85% increases in CNR and 17-29% increases in contrast relative to conventional B-mode imaging. However, despite its proven technical efficacy, the viability of fetal SLSC in the clinical ... Full text Cite

Notice of Removal: Clinical feasibility of a noninvasive method to interrogate myocardial function via strain and acoustic radiation force-derived stiffness

Conference IEEE International Ultrasonics Symposium Ius · October 31, 2017 Myocardial elastance, derived from pressure-volume (PV) loops in the left ventricle (LV), can be used to assess LV function and myocardial performance. This method requires an invasive intracardiac pressure-volume catheter to be inserted in the LV, limitin ... Full text Cite

Single track location comb-push ultrasound shear elastography (STL-CUSE)

Conference IEEE International Ultrasonics Symposium Ius · October 31, 2017 Single Track Location Shear Wave Elasticity Imaging (STL-SWEI) creates high resolution shear wave speed maps by comparing the tissue motion at each tracking location between spatially-offset radiation force excitations. While STL-SWEI circumvents the resol ... Full text Cite

Single track location Comb-Push Ultrasound Shear Elastography (STL-CUSE)

Conference IEEE International Ultrasonics Symposium Ius · October 31, 2017 Comb-Push Ultrasound Shear Elastography (CUSE) uses ultrasound beams focused simultaneously at multiple laterally-offset positions to induce shear waves in tissue, and uses the local propagation of the waves to estimate tissue elasticity everywhere in the ... Full text Cite

Feasibility of Swept Synthetic Aperture Ultrasound Imaging.

Journal Article IEEE transactions on medical imaging · July 2016 Ultrasound image quality is often inherently limited by the physical dimensions of the imaging transducer. We hypothesize that, by collecting synthetic aperture data sets over a range of aperture positions while precisely tracking the position and orientat ... Full text Open Access Cite

Safety Assessment of Advanced Imaging Sequences I: Measurements.

Journal Article IEEE transactions on ultrasonics, ferroelectrics, and frequency control · January 2016 A method for rapid measurement of intensities (I(spta)), mechanical index (MI), and probe surface temperature for any ultrasound scanning sequence is presented. It uses the scanner's sampling capability to give an accurate measurement of the whole imaging ... Full text Cite

Acoustic radiation force-based ultrasound elastography for cardiac imaging applications

Chapter · January 1, 2016 This chapter reviews the current research and applications for acoustic radiation force (ARF)‐based methods, namely ARF impulse (ARFI) imaging and shear wave elasticity imaging (SWEI) methods, in the diagnosis and treatment of cardiac diseases. ARFI imagin ... Full text Cite

In vivo transthoracic measurements of acoustic radiation force induced displacements in the heart over the cardiac cycle

Conference 2015 IEEE International Ultrasonics Symposium Ius 2015 · November 13, 2015 Myocardial elasticity is an important indicator of cardiac function and is affected in many disorders associated with heart failure. Ultrasound based interrogation of cardiac stiffness has been extensively studied in ex-vivo, open chest and intracardiac im ... Full text Cite

Phantom and in vivo demonstration of swept synthetic aperture imaging

Conference 2015 IEEE International Ultrasonics Symposium Ius 2015 · November 13, 2015 Ultrasound imaging of deep abdominal targets suffers from low lateral resolution due to limited aperture size and low-frequency transmit pulses. We demonstrate phantom and in vivo imaging results using a device that allows a tracked mechanical sweep of a c ... Full text Cite

Transverse oscillation vector flow imaging for transthoracic echocardiography

Conference Progress in Biomedical Optics and Imaging Proceedings of SPIE · January 1, 2015 This work presents the development and first results of in vivo transthoracic cardiac imaging using an implementation of Vector Flow Imaging (VFI) via the Transverse Oscillation (TO) method on a phased-array transducer. Optimal selection of the lateral wav ... Full text Cite

Contrast in intracardiac acoustic radiation force impulse images of radiofrequency ablation lesions.

Journal Article Ultrason Imaging · April 2014 We have previously shown that intracardiac acoustic radiation force impulse (ARFI) imaging visualizes tissue stiffness changes caused by radiofrequency ablation (RFA). The objectives of this in vivo study were to (1) quantify measured ARFI-induced displace ... Full text Open Access Link to item Cite

Acoustic radiation force impulse imaging (ARFI) on an IVUS circular array.

Journal Article Ultrasonic imaging · April 2014 Our long-term goal is the detection and characterization of vulnerable plaque in the coronary arteries of the heart using intravascular ultrasound (IVUS) catheters. Vulnerable plaque, characterized by a thin fibrous cap and a soft, lipid-rich necrotic core ... Full text Open Access Cite

Real-time GPU implementation of transverse oscillation vector velocity flow imaging

Conference Progress in Biomedical Optics and Imaging Proceedings of SPIE · January 1, 2014 Rapid estimation of blood velocity and visualization of complex flow patterns are important for clinical use of diagnostic ultrasound. This paper presents real-time processing for two-dimensional (2-D) vector flow imaging which utilizes an off-the-shelf gr ... Full text Cite

Acoustic radiation force impulse imaging on an IVUS circular array

Conference IEEE International Ultrasonics Symposium Ius · December 1, 2013 Our long-term goal is the detection and characterization of vulnerable plaque in the coronary arteries of the heart using IVUS catheters. Vulnerable plaque, characterized by a thin fibrous cap and a soft, lipid-rich, necrotic core is a pre-cursor to heart ... Full text Cite

Intracardiac acoustic radiation force impulse (ARFI) and shear wave imaging in pigs with focal infarctions.

Journal Article IEEE transactions on ultrasonics, ferroelectrics, and frequency control · August 2013 Four pigs, three with focal infarctions in the apical intraventricular septum (IVS) and/or left ventricular free wall (LVFW), were imaged with an intracardiac echocardiography (ICE) transducer. Custom beam sequences were used to excite the myocardium with ... Full text Open Access Cite

NOVEL APPLICATION OF ACOUSTIC RADIATION FORCE IMPULSE IMAGING IN TRANSTHORACIC ECHOCARDIOGRAPHY

Conference Journal of the American College of Cardiology · March 2013 Full text Cite

Confirmation of cardiac radiofrequency ablation treatment using intra-procedure acoustic radiation force impulse imaging

Conference IEEE International Ultrasonics Symposium Ius · December 1, 2012 Recurrence of atrial fibrillation after transcatheter ablation (TCA) is common because there is no imaging modality that can visually confirm the presence of radiofrequency ablation (RFA) lesions. We have previously shown that acoustic radiation force impu ... Full text Cite

Feasibility and safety of transthoracic cardiac acoustic radiation force impulse imaging methods

Conference IEEE International Ultrasonics Symposium Ius · December 1, 2012 This work examines clinical feasibility of using non-invasive transthoracic echocardiography techniques to visualize temporal variations of stiffness through the cardiac cycle using acoustic radiation force impulse (ARFI) imaging. © 2012 IEEE. ... Full text Cite

Intracardiac ARF-driven shear wave velocimetry to estimate regional myocardial stiffness and contractility in pigs with focal infarctions

Conference IEEE International Ultrasonics Symposium Ius · December 1, 2012 Four pigs, three with focal infarctions in the apical intraventricular septum (IVS) and/or left ventricular free wall (LVFW), were imaged with an intracardiac echocardiography (ICE) transducer. Custom beam sequences were used to excite the myocardium with ... Full text Cite

Intracardiac acoustic radiation force impulse imaging: a novel imaging method for intraprocedural evaluation of radiofrequency ablation lesions.

Journal Article Heart Rhythm · November 2012 BACKGROUND: Arrhythmia recurrence after cardiac radiofrequency ablation (RFA) for atrial fibrillation has been linked to conduction through discontinuous lesion lines. Intraprocedural visualization and corrective ablation of lesion line discontinuities cou ... Full text Open Access Link to item Cite

Direct in vivo myocardial infarct visualization using 3D ultrasound and passive strain contrast

Conference IEEE International Ultrasonics Symposium Ius · December 1, 2011 An approach for myocardial elastography is presented for infarct visualization. Infarcts are visualized using passive strain in the ventricles induced by atrial contraction. Results are compared against ARFI and delay-enhanced contrast MR. © 2011 IEEE. ... Full text Cite

Acoustic radiation force-based elasticity imaging methods.

Journal Article Interface focus · August 2011 Conventional diagnostic ultrasound images portray differences in the acoustic properties of soft tissues, whereas ultrasound-based elasticity images portray differences in the elastic properties of soft tissues (i.e. stiffness, viscosity). The benefit of e ... Full text Cite

Near real time evaluation of cardiac radiofrequency ablation lesions with intracardiac echocardiography based acoustic radiation force impulse imaging.

Journal Article The Journal of the Acoustical Society of America · April 1, 2011 [Cardiac radiofrequency (rf) ablation is used to treat cardiac arrhythmias. Multiple rf lesions are created to form lines of electrical block to disrupt arrhythmic wavefronts. However, image based lesion evaluation is not performed and clinicians r ... Full text Cite

Intracardiac measurements of elasticity using Acoustic Radiation ForceImpulse (ARFI) methods: Temporal and spatial stability of shear wave velocimetry

Journal Article Proceedings IEEE Ultrasonics Symposium · December 1, 2010 Acoustic Radiation Force Impulse (ARFI) methods have been validated formeasuring tissue elastic properties, with shear wave velocimetry emerging as aquantitative way to measure stiffness. Using ultrasound to interrogate cardiacelasticity holds promise for ... Full text Cite

Parametric pressure-volume analysis and acoustic radiation force impulse imaging of left ventricular function

Conference Proceedings IEEE Ultrasonics Symposium · December 1, 2010 Extensive research has been devoted to the quantification of left ventricular (LV) function via an elasticity metric known as elastance. Similar to a stress-strain relation, yielding stiffness, myocardial elastance is measured from the pressure-volume (PV) ... Full text Cite

In vivo guidance and assessment of liver radio-frequency ablation with acoustic radiation force elastography.

Journal Article Ultrasound Med Biol · October 2008 The initial results from clinical trials investigating the utility of acoustic radiation force impulse (ARFI) imaging for use with radio-frequency ablation (RFA) procedures in the liver are presented. To date, data have been collected from 6 RFA procedures ... Full text Open Access Link to item Cite

Impulsive acoustic radiation force: imaging approaches and clinical applications

Journal Article The Journal of the Acoustical Society of America · May 1, 2008 Focused acoustic radiation force can be used to locally mechanically excite tissue, and the tissue response can be monitored with conventional ultrasonic displacement estimation methods. Many groups are currently exploring the potential for radiati ... Full text Cite

In vivo visualization of abdominal malignancies with acoustic radiation force elastography.

Journal Article Phys Med Biol · January 7, 2008 The utility of acoustic radiation force impulse (ARFI) imaging for real-time visualization of abdominal malignancies was investigated. Nine patients presenting with suspicious masses in the liver (n = 7) or kidney (n = 2) underwent combined sonography/ARFI ... Full text Open Access Link to item Cite

Transthoracic cardiac acoustic radiation force impulse imaging: A feasibility study

Conference Proceedings IEEE Ultrasonics Symposium · December 1, 2007 We describe new non-invasive techniques for visualizing local variations of stiffness in cardiac tissue through the use of transthoracic acoustic radiation force impulse (ARFI) imaging. Custom M-mode and two-dimensional ARFI sequences were implemented on t ... Full text Cite

In vivo Acoustic Radiation Force Impulse imaging of abdominal lesions

Conference Proceedings IEEE Ultrasonics Symposium · December 1, 2007 The initial results from an ongoing clinical study investigating the utility of Acoustic Radiation Force Impulse (ARFI) imaging for in vivo visualization of abdominal lesions are presented. To date, 13 patients with lesions located in the liver (n = 11) or ... Full text Cite

Ivory Towers

Conference In Hollywood, there is a game and computer science problem known as the "Six Degrees of Kevin Bacon" in which almost any actor can be linked to Kevin Bacon through a number of movies and other actors. For most actors the number of links is less than 6, and ... Open Access Cite