Flow quantification with high-frequency (>20 MHz) power Doppler ultrasound can be performed objectively using the wall-filter selection curve (WFSC) method to select the cutoff velocity that yields a best-estimate color pixel density (CPD). An in vivo video microscopy system (IVVM) is combined with high-frequency power Doppler ultrasound to provide a method for validation of CPD measurements based on WFSCs in mouse testicular vessels. The ultrasound and IVVM systems are instrumented so that the mouse remains on the same imaging platform when switching between the two modalities. In vivo video microscopy provides gold-standard measurements of vascular diameter to validate power Doppler CPD estimates. Measurements in four image planes from three mice exhibit wide variation in the optimal cutoff velocity and indicate that a predetermined cutoff velocity setting can introduce significant errors in studies intended to quantify vascularity. Consistent with previously published flow-phantom data, in vivo WFSCs exhibited three characteristic regions and detectable plateaus. Selection of a cutoff velocity at the right end of the plateau yielded a CPD close to the gold-standard vascular volume fraction estimated using IVVM. An investigator can implement the WFSC method to help adapt cutoff velocity to current blood flow conditions and thereby improve the accuracy of power Doppler for quantitative microvascular imaging.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.ultrasmedbio.2014.02.030 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Usefulness of Aortic Valve Calcification in Patients With Low-Flow Aortic Stenosis.
Circ Cardiovasc Imaging
January 2025
Department of Cardiology, Odense University Hospital, Denmark (N.S.B.M., J.S.D., M.A., A.H., R.C.-S., J.E.M., K.A.Ø., M.-A.C.).
Background: Aortic valve calcification (AVC) has been shown to be a powerful assessment of aortic stenosis (AS) severity and a predictor of adverse outcomes. However, its accuracy in patients with low-flow AS has not yet been proven. The objective of the study was to assess the predictive value of AVC in patients with classical low-flow (CLF, that is, low-flow reduced left ventricular ejection fraction) or paradoxical low-flow (PLF, that is, low-flow preserved left ventricular ejection fraction) AS.
View Article and Find Full Text PDFUAV Trajectory Control and Power Optimization for Low-Latency C-V2X Communications in a Federated Learning Environment.
Sensors (Basel)
December 2024
Department of Electrical, Computer and Biomedical Engineering, Toronto Metropolitan University, Toronto, ON M5B2K3, Canada.
Unmanned aerial vehicle (UAV)-enabled vehicular communications in the sixth generation (6G) are characterized by line-of-sight (LoS) and dynamically varying channel conditions. However, the presence of obstacles in the LoS path leads to shadowed fading environments. In UAV-assisted cellular vehicle-to-everything (C-V2X) communication, vehicle and UAV mobility and shadowing adversely impact latency and throughput.
View Article and Find Full Text PDFContrast-enhanced ultrasound as a valuable tool to detect minimal inflammation in RA patients in sustained remission.
Front Med (Lausanne)
December 2024
Rheumatology Department, Unidade Local de Saúde de Santa Maria, Lisbon, Portugal.
Objective: The study aimed to explore the utility of contrast-enhanced ultrasound (CEUS) as a tool for detecting minimal inflammation in rheumatoid arthritis (RA) patients in sustained remission (SR) and to correlate the findings with Disease Activity Score 28 (DAS28) status scores and various ultrasound (US) scores.
Patients And Methods: Thirty RA patients in SR (minimum 6 months), 12 with active disease, and 10 healthy controls were included. Clinical evaluations and US assessments were performed, including grayscale US (GSUS), power Doppler US (PDUS), and Global OMERACT-EULAR Synovitis Score (GLOESS).
Aims: ultrasound (US) diagnosis of enthesitis is burdened of low specificity, especially when it is performed in patients with psoriasis (PsO) but without clinical psoriatic arthritis (PsA), because of mechanical, dysmetabolic and age-related concurrent enthesopatic changes. We propose a novel US score to quantify the cortical-entheseal bone remodeling burden of several peripheral entheses, aiming to improve the specificity of US for PsA-related enthesitis, and to evaluate its diagnostic value in PsO patients with subsequent diagnosis of psoriatic arthritis (PsO/PsA).
Methods: clinical and US data of 119 consecutive patients with moderate/severe PsO and nonspecific musculoskeletal symptoms, were included in this retrospective study.
Midinfrared Cavity-Enhanced Two-Photon Absorption Spectroscopy for Selective Detection of Trace Gases.
Anal Chem
January 2025
Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China.
Detection of trace gases, such as radioactive carbon dioxide, clumped isotopes, and reactive radicals, is of great interest and poses significant challenges in various fields. Achieving both high selectivity and high sensitivity is essential in this context. We present a highly selective molecular spectroscopy method based on comb-locked, mid-infrared, cavity-enhanced, two-photon absorption.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!