A5066345001- Ultrasound Imaging and Elastography
- Photoacoustic and Ultrasonic Imaging
- Elasticity and Material Modeling
- Ultrasound and Hyperthermia Applications
- Ultrasonics and Acoustic Wave Propagation
- Scoliosis diagnosis and treatment
- Cardiac Valve Diseases and Treatments
- Surgical Simulation and Training
- Sparse and Compressive Sensing Techniques
- Robotics and Sensor-Based Localization
- Medical Imaging and Analysis
- Advanced MRI Techniques and Applications
- Muscle activation and electromyography studies
- Inertial Sensor and Navigation
- Flow Measurement and Analysis
- Medical Image Segmentation Techniques
- Myofascial pain diagnosis and treatment
- Electrical and Bioimpedance Tomography
- Augmented Reality Applications
- Image and Signal Denoising Methods
Concordia University
2019-2024
Johns Hopkins University
2024
With the widespread interest and uptake of super-resolution ultrasound (SRUS) through localization tracking microbubbles, also known as microscopy (ULM), many algorithms have been developed. ULM can image centimeters into tissue in-vivo track microvascular flow non-invasively with sub-diffraction resolution. In a significant community effort, we organized challenge, Ultrasound Localization TRacking Algorithms for Super-Resolution (ULTRA-SR). The aims this paper are threefold: to describe...
In this paper, a novel computationally efficient quasi-static ultrasound elastography technique is introduced by optimizing an energy function. Unlike conventional techniques, three radio frequency (RF) frames are considered to devise nonlinear cost function consisting of data intensity similarity term, spatial regularization terms and, most importantly, temporal continuity terms. We optimize the aforesaid efficiently obtain time-delay estimation (TDE) all samples between first two and last...
Convolutional Neural Networks (CNN) have shown promising results for displacement estimation in UltraSound Elastography (USE). Many modifications been proposed to improve the of CNNs USE axial direction. However, lateral strain, which is essential several downstream tasks such as inverse problem elasticity imaging, remains a challenge. The strain complicated since motion and sampling frequency this direction are substantially lower than one, lack carrier signal In computer vision...
Ultrasound speckle tracking has the potential to quantify shear strain in patients with myofascial pain, leading previous clinical conclusions (derived from a cross-correlation-based, windowed-search method) that is altered pain when compared healthy individuals. However, differences speckle-tracking techniques are known impact accuracy of estimated displacement fields, which alter conclusions. Therefore, this work aims assess reliability two estimation algorithms context muscle lateral...
Ultrasound elastography is a prominent noninvasive medical imaging technique that estimates tissue elastic properties to detect abnormalities in an organ. A common approximation modulus strain induced after mechanical stimulation. To compute strain, ultrasound radio frequency (RF) data can be processed using energy-based algorithms. These algorithms suffer from ill-posedness tackle. continuity constraint along with the amplitude similarity imposed obtain unique solution time-delay estimation...
Time delay estimation (TDE) between two radio-frequency (RF) frames is one of the major steps quasi-static ultrasound elastography, which detects tissue pathology by estimating its mechanical properties. Regularized optimization-based techniques, a prominent class TDE algorithms, optimize nonlinear energy functional consisting data constancy and spatial continuity constraints to obtain displacement strain maps time-series under consideration. The existing methods often consider L2 -norm...
In this work, a novel technique for real-time clutter rejection in ultrasound Color Flow Imaging (CFI) is proposed. Suppressing undesired signal important because prohibits an unambiguous view of the vascular network. Although conventional eigen-based filters are potentially efficient suppressing signal, their performance highly dependent on proper selection to blood boundary which done manually. Herein, we resolve limitation by formulating suppression problem as foreground-background...
Tracking the displacement between pre- and post-deformed radio-frequency (RF) frames is a pivotal step of ultrasound elastography, which depicts tissue mechanical properties to identify pathologies. Due ultrasound's poor ability capture information pertaining lateral direction, existing estimation techniques fail generate an accurate or strain map. The attempts made in literature mitigate this well-known issue suffer from one following limitations: 1) Sampling size substantially increased,...
Abstract Background Ultrasound strain imaging, which delineates mechanical properties to detect tissue abnormalities, involves estimating the time delay between two radio‐frequency (RF) frames collected before and after deformation. The existing regularized optimization‐based time‐delay estimation (TDE) techniques suffer from at least one of following drawbacks: (1) regularizer is not aligned with deformation physics due taking only first‐order displacement derivative into account; (2) ‐norm...
A recent technique named Mechanically-inspired L1-norm-based Second-Order Ultrasound eLastography (L1- MechSOUL) has provided a promising solution to the well-known issue of 2D tracking (both axial and lateral) in ultrasound strain elastography. This optimizes cost function consisting data term, mechanical congruence first- second-order continuity terms. However, L1-MechSOUL's regularizer considers only unmixed second derivatives disregards mixed derivatives, which is simplification that...
Energy-based displacement tracking of ultrasound images can be implemented by optimizing a cost function consisting data term, mechanical congruency and first- second-order continuity terms. This approach recently provided promising solution to two-dimensional axial lateral in strain elastography. However, the associated regularizer only considers unmixed second derivatives disregards mixed derivatives, thereby providing suboptimal noise suppression limiting possibilities for total tensor...
Energy-based ultrasound elastography techniques minimize a regularized cost function consisting of data and continuity terms to obtain local displacement estimates based on the time-delay estimation (TDE) between radio frequency (RF) frames. The term associated with existing takes only amplitude similarity into account hence is not sufficiently robust outlier samples present in RF frames under consideration. This drawback creates noticeable artifacts strain image. To resolve this issue, we...
Ultrasound data often suffers from an excessive amount of noise especially deep tissue or in synthetic aperture imaging where the acoustic wave is weak. Such noisy renders Time Delay Estimation (TDE) inaccurate context ultrasound elastography. Herein, a novel two-step elastography technique presented to ensure accurate TDE while dealing with data. In first step, instead one, we acquire several Radio-Frequency (RF) frames both pre- and post-deformed positions tissue. We stack collected planes...
In this paper, we propose a novel framework for time delay estimation in ultrasound elastography. the presence of high acquisition noise, state-of-the-art motion tracking techniques suffer from inaccurate displacement field. To resolve issue, instead one, collect several Radio-Frequency (RF) frames both pre- and post-deformed scan planes to better investigate data statistics. We formulate non-linear cost function incorporating all observation levels deformations. Beside similarity, impose...
Regularized optimization-based ultrasound elastography techniques minimize an energy function consisting of data and continuity terms to obtain the displacement tensor between radio-frequency (RF) frames. The term associated with existing energy-based takes only amplitude similarity into account hence lacks robustness outlier samples present in RF This drawback creates noticeable artifacts strain image. To address this issue, we devise as a linear combination gradient residuals. We follow...
In this paper, we propose a novel technique for suppressing clutter in ultrasound Color Flow Imaging (CFI). The unexpected signal originating from slowly moving tissue prevents clear visualization of vasculature. Using eigen-based filters is state-of-the-art to reject the echo. However, it remains an issue find exact rank and blood subspaces these algorithms. Additionally, case noisy data, linear lead inefficient suppression clutter. Moreover, conventional methods are subject lengthy...
Ultrasound localization microscopy (ULM) refers to a promising medical imaging modality that systematically leverages the advantages of contrast-enhanced ultrasound (CEUS) surpass diffraction barrier and delineate microvascular map. Localization tracking microbubbles (MBs), two significant steps ULM, facilitate generating vascular map velocity distribution, respectively. Herein, we propose novel MB technique considering temporal pairing as bubble-set registration problem. Iterative is...
Tracking the displacement between pre- and post-deformed radio-frequency (RF) frames is a pivotal step of ultrasound elastography, which depicts tissue mechanical properties to identify pathologies. Due ultrasound's poor ability capture information pertaining lateral direction, existing estimation techniques fail generate an accurate or strain map. The attempts made in literature mitigate this well-known issue suffer from one following limitations: 1) Sampling size substantially increased,...
Intraoperative tracking of surgical instruments is an inevitable task computer-assisted surgery. An optical system often fails to precisely reconstruct the dynamic location and pose a tool due acquisition noise measurement variance. Embedding Kalman Filter (KF) or any its extensions such as extended unscented filters with tracker resolves this issue by reducing estimation variance regularizing temporal behavior. However, current rigid-body KF implementations are computationally burdensome...
Energy-based ultrasound elastography techniques minimize a regularized cost function consisting of data and continuity terms to obtain local displacement estimates based on the time-delay estimation (TDE) between radio-frequency (RF) frames. The term associated with existing takes only amplitude similarity into account hence is not sufficiently robust outlier samples present in RF frames under consideration. This drawback creates noticeable artifacts strain image. To resolve this issue, we...