Mayo Foundation for Medical Education and Research

Other

University of Utah Research Foundation

James Fowler Greenleaf

Shigao Chen

Matthew W Urban

Pengfei Song

Armando Manduca

Heng Zhao

Yi Zheng

Carolina Amador Carrascal

Mostafa Fatemi-Booshehri

Bo Qiang

Daniel C Mellema

Mostafa Fatemi

Aiping Yao

Jian-yu Lu

Randall Kinnick

Xiaoming Zhang

Richard L Ehman

Joshua D Trzasko

Steven A Johnson

Arlen Dale Hanssen

Michael J Yaszemski

Kai-Nan An

Chunfeng Zhao

Robin Patel

Xiaohui Hao

Peter C Amadio

Ivan Z Nenadic

Alireza Nabavizadehrafsanjani

Mark R Pittelkow

Nicholas James Hangiandreou

Ping He

Juha T Ylitalo

Christine U Lee

James L Herrick

Alan L Miller, Ii

Yuexiang Wang

James W Jakub

Benjamin G Wood

Nathan J Brinkman

Margherita Capriotti

Hyungkyi Lee

Andrej Trampuz

Thomas M Huber

Wei Tan

Joseph William Charboneau

Markers (e.g., treatment site markers, biopsy site markers) are composed of a non-metallic material having a composition and/or other features or characteristics such that the markers will generate twinkling artifacts when imaged with ultrasound. In this way, the composition of the markers enables their detection and localization using ultrasound. The markers are generally composed of non-metallic materials that enhance the twinkling artifact.

Non-metallic ultrasound-detectable markers

Systems and methods for Plane Wave Compounding ('PWC') are provided for improving image quality with reduced phase shift errors. The initial phase difference (“IPD”) between two PW transmissions is related to the phase shift error. When the absolute value of IPD is larger than π/2, the phase shift error occurs. An Initial-Phase-Compensated PWC (“IPCPWC”) method may be used to compensate the initial phase of echo signals from each PW transmit and maintain the absolute value of IPD smaller than π/2. IPCPWC methods may also include increased motion signal-to-noise ratio and reduced jitter.

Systems and methods for plane wave compounding in ultrasound imaging

Shear wave elastography and/or other ultrasound imaging procedures are performed using a data acquisition technique in which data are acquired with high SNR while maintaining a high PRF, using conventional clinical ultrasound scanners. In general, ultrasound data are acquired using plane waves at different angles, after which a time alignment process is applied to the acquired data. The time alignment uses interpolation to obtain data points at higher frame rates, and the time-aligned data is compounded to increase the SNR.

Time-aligned plane wave compounding of ultrasound data

Systems and methods for processing data acquired using ultrasound elastography, in which shear waves are generated in a subject using continuous vibration of an ultrasound transducer, are provided. The systems and methods described here can effectively remove motion artifacts associated with vibration of the ultrasound transducer, and can also remove the data sampling misalignment caused when a line-by-line imaging mode is used to acquire data, as is done by many conventional ultrasound scanners. Thus, the systems and methods described here provide techniques for transducer motion correction and for aligning motion signals detected by line-by-line scanning ultrasound systems.

Systems and methods for ultrasound elastography with continuous transducer vibration

Systems and methods for performing shear wave elastography using push and/or detection ultrasound beams that are generated by subsets of the available number of transducer elements in an ultrasound transducer. These techniques provide several advantages over currently available approaches to shear wave elastography, including the ability to use a standard, low frame rate ultrasound imaging system and the ability to measure shear wave speed throughout the entire field-of-view rather than only those regions where the push beams are not generated.

System and method for shear wave elastography by transmitting ultrasound with subgroups of ultrasound transducer elements

Methods for processing data acquired using ultrasound elastography, in which shear waves are generated in a subject using continuous vibration of the ultrasound transducer, are described. The described methods can effectively separate shear wave signals from signals corresponding to residual motion artifacts associated with vibration of the ultrasound transducer. The systems and methods described here also provide for real-time visualization of shear waves propagating in the subject.

Shear wave elastography with ultrasound probe oscillation

Described here are systems and methods for estimating shear wave velocity from data acquired with a shear wave elastography system. More particularly, the systems and methods described here implement a spatiotemporal time-to-peak algorithm that searches for the times at which shear wave motion is at a maximum while also searching for the lateral locations at which shear wave motion is at a maximum. Motion can include displacement, velocity, or acceleration caused by propagating shear waves. A fitting procedure (e.g., a linear fit) is performed on a combined set of these temporal peaks and spatial peaks to estimate the shear wave velocity, from which mechanical properties can be computed. Motion amplitude thresholding can also be used to increase the number of points for the fitting.

Shear wave group velocity estimation using spatiotemporal peaks and amplitude thresholding

Methods for measuring mechanical properties of an object or subject under examination with an ultrasound system and using unfocused ultrasound energy are provided. Shear waves that propagate in the object or subject are produced by applying unfocused ultrasound energy to the object or subject, and measurement data is acquired by applying focused or unfocused ultrasound energy to at least one location in the object or subject at which shear waves are present Mechanical properties are then calculated from the acquired measurement data.

Ultrasound vibrometry with unfocused ultrasound

A method for imaging an object by ultrasound elastography through continuous vibration of the ultrasound transducer is taught. An actuator directly in contact with the ultrasound transducer continuously vibrates the transducer in an axial direction, inducing shear waves in the tissue and allowing for real-time shear wave imaging. Axial motion of the transducer contaminates the shear wave images of the tissue, and must be suppressed. Therefore, several methods for correcting for shear wave artifact caused by the motion of the transducer are additionally taught.

Method for ultrasound elastography through continuous vibration of an ultrasound transducer

A model-independent method for producing a viscoelastic tissue property metric using ultrasound is provided. A mechanical stress, such as an acoustic force, is applied to a tissue using an ultrasound system and tissue displacement resulting from the applied acoustic force is measured. From the tissue displacement measurements, a complex modulus, such as a relative complex modulus, is extracted. A loss tangent is calculated from the extracted complex modulus. Using the calculated loss tangent, viscoelastic tissue property metrics may be calculated.

System and method for model-independent quantification of tissue viscoelastic properties using ultrasound

A model-independent method for producing a viscoelastic tissue property metric using ultrasound is provided. A mechanical stress, such as an acoustic force, is applied to a tissue during a creep period using an ultrasound system to generate a creep response. Tissue displacement resulting from the applied acoustic force is measured during a recovery period following the creep period. From the tissue displacement measurements, a relative complex modulus is extracted, and a loss tangent is calculated based on extracted complex modulus. Using the calculated loss tangent, viscoelastic tissue property metrics may be calculated.

System and method for acoustic radiation force creep-recovery and shear wave propagation elasticity imaging

A shear wave dispersion ultrasound vibrometry ('SDUV') method for measuring a mechanical property of a subject is provided. Particularly, a set of ultrasonic vibration tone bursts is applied to a vibration origin in the subject so that harmonic vibratory motion is imparted to a tissue of interest. The set of vibration tone bursts effectively act like a single vibration pulse that imparts vibratory motion at larger amplitudes than achievable with a single pulse. Multiple ultrasonic detection pulses are then applied to two or more locations in the tissue of interest in order to measure shear waves propagating outward from the vibration origin. From these measurements, phase or amplitude information related to the shear wave propagation is determined and used to calculate a shear wave speed. Using the shear wave speed information, mechanical properties of the tissue are calculated.

Method for shear wave ultrasound vibrometry with interleaved push and detection pulses

Described here are systems and methods for ultrasound processes using shear wave attenuation and velocity derived from k-space analysis by analyzing spatial frequency domain data.

System and method for gradient-based k-space search for shear wave velocity dispersion estimation

Growing community of inventors

Rochester, MN, United States of America

James Fowler Greenleaf