A5009833478- Ultrasound Imaging and Elastography
- Ultrasound and Hyperthermia Applications
- Photoacoustic and Ultrasonic Imaging
- Ultrasonics and Acoustic Wave Propagation
- Preterm Birth and Chorioamnionitis
- Medical Imaging Techniques and Applications
- Digital Radiography and Breast Imaging
- AI in cancer detection
- Radiomics and Machine Learning in Medical Imaging
- Ultrasound in Clinical Applications
- Bone health and osteoporosis research
- Flow Measurement and Analysis
- Elasticity and Material Modeling
- Optical Imaging and Spectroscopy Techniques
- Advanced X-ray and CT Imaging
- Medical Image Segmentation Techniques
- Radiation Dose and Imaging
- Advanced MRI Techniques and Applications
- Liver Disease Diagnosis and Treatment
- Infrared Thermography in Medicine
- Pregnancy-related medical research
- Spectroscopy Techniques in Biomedical and Chemical Research
- Bone fractures and treatments
- Breast Cancer Treatment Studies
- Advanced Radiotherapy Techniques
University of Wisconsin–Madison
2016-2025
Massachusetts General Hospital
2023
Harvard University
2023
Universidad Nacional Autónoma de México
2009-2021
Concordia University
2021
Instituto de Física La Plata
2021
University of Illinois Urbana-Champaign
2015
Highland Community College - Illinois
2012-2013
Instituto Nacional de Cancerología
2011
Mexican Social Security Institute
2011
Backscatter and attenuation coefficient estimates are needed in many quantitative ultrasound strategies. In clinical applications, these parameters may not be easily obtained because of variations scattering by tissues overlying a region interest (ROI). The goal this study is to assess the accuracy backscatter for regions distal nonuniform layers tissue-mimicking materials. addition, work compares results “layered” phantoms scanned using different machines. Two were constructed, each...
One of the main limitations ultrasound imaging is that image quality and interpretation depend on skill user experience clinician. Quantitative (QUS) methods provide objective, system-independent estimates tissue properties, such as acoustic attenuation backscattering properties tissue, which are valuable objective tools for both diagnosis intervention. Accurate precise estimation these requires correct compensation intervening attenuation. Prior attempts to estimate intervening-tissue based...
In vivo estimations of the frequency-dependent acoustic attenuation (α) and backscatter (η) coefficients using radiofrequency (rf) echoes acquired with clinical ultrasound systems must be independent data acquisition setup estimation procedures. a recent in assessment these parameters rodent mammary tumors, overall agreement was observed among α η estimates from four imaging systems. some cases, particularly highly-attenuating heterogeneous multisystem variability observed. This paper...
Quantitative ultrasound (QUS) analyzes the (US) backscattered data to find properties of scatterers that correlate with tissue microstructure. Statistics envelope radio frequency (RF) can be utilized estimate several QUS parameters. Different distributions have been proposed model data. The homodyned K-distribution (HK-distribution) is one most comprehensive US under diverse scattering conditions (varying scatterer number density and coherent scattering). clustering parameter ( α ) ratio...
Ultrasonic attenuation may be measured accurately with clinical systems and array transducers by using reference phantom methods (RPM) to account for diffraction other system dependencies on echo signals. Assumptions the RPM are that speeds of sound in sample (c(sam)) medium (c(ref)) same they match speed assumed beamformer (c(bf)). This work assesses accuracy measurements when these assumptions not met. Attenuation was two homogeneous phantoms, one a 1500 m/s 1580 m/s. Both have an...
A key step toward implementing quantitative ultrasound techniques in a clinical setting is demonstrating that parameters such as the ultrasonic backscatter coefficient (BSC) can be accurately estimated independent of imaging system used. In previous studies, agreement BSC estimates for well characterized phantoms was demonstrated across different laboratory systems. The goal this study to compare tissue mimicking sample measured using four scanners, each providing RF echo data 1-15 MHz...
Reported here is a phantom-based comparison of methods for determining the power spectral density (PSD) ultrasound backscattered signals. Those values are then used to estimate parameters describing α( f), frequency dependence acoustic attenuation coefficient. Phantoms were scanned with clinical system equipped research interface obtain radiofrequency echo data. Attenuation, modeled as law f) = α 0 f β , was estimated using reference phantom method. The short-time Fourier transform (STFT),...
Regularized estimation of quantitative ultrasound (QUS) parameters, such as attenuation and backscatter coefficients, has gained research interest. Recently, the alternating direction method multipliers (ADMM) been applied successfully to estimate these by utilizing L2 L1 norms for coefficient regularization, respectively. While this improves upon previous approaches, it does not fully leverage prior knowledge minimum physically feasible parameter values, sometimes yielding values outside...
Speckle statistics estimation is a useful quantitative ultrasound tool for characterizing tissue microstructure. However, because of their elongated geometry, fibrillar components like collagen may not be described well by speckle models. The purpose this study to perform systematic analysis the effects microstructural anisotropy on estimation. We created phantoms made wool fibers correlate estimates scatterer geometries. Phantoms were attached calibrated spring induce fiber alignment...
Abstract Metabolic dysfunction‐associated steatotic liver disease (MASLD) typically presents as “macrovesicular steatosis”, where each hepatocyte contains a large fat vacuole (30‐50 µm), indicating more indolent form. In about 20% of cases, “microvesicular steatosis” occurs, with smaller vacuoles (1‐15 µm) linked to steatohepatitis, cirrhosis progression, and increased risk cancer. Emerging quantitative ultrasound (QUS) quantification (QUS‐LFQ) tools measure various acoustic properties, but...
The uterine cervix is a soft biological tissue with critical biomechanical functions in pregnancy. It mechanical barrier that supports the growing fetus. As pregnancy progresses, becomes more compliant and eventually opens late to facilitate childbirth. This dual function facilitated by extensive remodeling of cervical extracellular matrix (ECM), giving rise its complex time-dependent material properties. Premature known result preterm birth, defined as birth before 37 weeks gestation. While...
The estimation of many spectral-based quantitative ultrasound parameters assumes that backscattered echo signals are from a stationary, incoherent scattering process. accuracy these assumptions in real tissue can limit the diagnostic value and physical insight about microstructure they convey. This work presents an empirical decision test to determine presence significant coherent contributions whether caused by low scatterer number densities or specular reflectors scatterers with periodic...
We report here the results of a longitudinal study cervix stiffness during pregnancy. Thirty women, ages ranging from 19 to 37 years, were scanned with ultrasound at five time points beginning their normal first-trimester screening (8-13 weeks) through term pregnancy (nominally 40 week) using clinical imaging system modified special transducer and software. The estimated shear wave speed (its square proportional modulus under idealized conditions) in cervix. found constant fractional...
Although a variety of techniques have been developed to reduce the appearance B-mode speckle, quantitative ultrasound (QUS) aims at extracting hidden properties tissue. Herein, we propose two novel accurately and precisely estimate important QUS parameters, namely, average attenuation coefficient backscatter coefficient. Both optimize cost function that incorporates data continuity constraint terms, which call AnaLytical Global rEgularized BackscatteR quAntitative (ALGEBRA). We versions...
The American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) atlas for ultrasound (US) qualitatively describes the echogenicity attenuation a mass, where fat lobules serve as standard comparison. This study aimed to estimate acoustic properties breast under clinical imaging conditions determine degree which vary among patients.Twenty-four women with solid masses scheduled biopsy were scanned Siemens S2000 scanner 18L6 linear array transducer (Siemens Medical...
Quantitative ultrasound (QUS) can reveal crucial information on tissue properties, such as scatterer density. If the density per resolution cell is above or below 10, considered fully developed speckle (FDS) underdeveloped (UDS), respectively. Conventionally, has been classified using estimated statistical parameters of amplitude backscattered echoes. However, if patch size small, estimation not accurate. These are also highly dependent imaging settings. In this article, we adapt...