Influence of pulse repetition frequency and high pass filter on color Doppler maps of converging flow in vitro

1996 ◽  
Vol 12 (4) ◽  
pp. 257-261 ◽  
Author(s):  
Martin Giesler ◽  
Veit Göller ◽  
Alexander Pfob ◽  
Dionyz Bajtay ◽  
Matthias Kochs ◽  
...  
Keyword(s):  
Pulse Repetition Frequency ◽  
Color Doppler ◽  
Repetition Frequency ◽  
Pulse Repetition ◽  
Pass Filter ◽  
High Pass Filter ◽  
Converging Flow ◽  
High Pass

scholarly journals Effects of Non-thermal Ultrasound on a Fibroblast Monolayer Culture: Influence of Pulse Number and Pulse Repetition Frequency

Sensors ◽  
2021 ◽  
Vol 21 (15) ◽  
pp. 5040
Author(s):  
Silvia Ronda Peñacoba ◽  
Mar Fernández Gutiérrez ◽  
Julio San Román del Barrio ◽  
Francisco Montero de Espinosa
Keyword(s):  
Short Pulse ◽  
Pulse Repetition Frequency ◽  
Pulse Number ◽  
Repetition Frequency ◽  
Pulse Repetition ◽  
Treatment Protocols ◽  
Culture Plate ◽  
New Treatment ◽  
Long Pulse

Despite the use of therapeutic ultrasound in the treatment of soft tissue pathologies, there remains some controversy regarding its efficacy. In order to develop new treatment protocols, it is a common practice to carry out in vitro studies in cell cultures before conducting animal tests. The lack of reproducibility of the experimental results observed in the literature concerning in vitro experiments motivated us to establish a methodology for characterizing the acoustic field in culture plate wells. In this work, such acoustic fields are fully characterized in a real experimental configuration, with the transducer being placed in contact with the surface of a standard 12-well culture plate. To study the non-thermal effects of ultrasound on fibroblasts, two different treatment protocols are proposed: long pulse (200 cycles) signals, which give rise to a standing wave in the well with the presence of cavitation (ISPTP max = 19.25 W/cm2), and a short pulse (five cycles) of high acoustic pressure, which produces a number of echoes in the cavity (ISPTP = 33.1 W/cm2, with Pmax = 1.01 MPa). The influence of the acoustic intensity, the number of pulses, and the pulse repetition frequency was studied. We further analyzed the correlation of these acoustic parameters with cell viability, population, occupied surface, and cell morphology. Lytic effects when cavitation was present, as well as mechanotransduction reactions, were observed.

scholarly journals Effect of adenosine on short-term synaptic plasticity in mouse piriform cortex in vitro: adenosine acts as a high-pass filter

2019 ◽  
Vol 7 (3) ◽  
pp. e13992 ◽  
Author(s):  
Simon P. Perrier ◽  
Marie Gleizes ◽  
Caroline Fonta ◽  
Lionel G. Nowak
Keyword(s):  
Synaptic Plasticity ◽  
Piriform Cortex ◽  
Short Term ◽  
Pass Filter ◽  
High Pass Filter ◽  
High Pass

scholarly journals Influence of changing pulse repetition frequency on chemical and biological effects induced by low-intensity ultrasound in vitro

2009 ◽  
Vol 16 (3) ◽  
pp. 392-397 ◽  
Author(s):  
Mikhail A. Buldakov ◽  
Mariame A. Hassan ◽  
Qing-Li Zhao ◽  
Loreto B. Feril ◽  
Nobuki Kudo ◽  
...  
Keyword(s):  
Biological Effects ◽  
Pulse Repetition Frequency ◽  
Repetition Frequency ◽  
Pulse Repetition ◽  
Low Intensity ◽  
Low Intensity Ultrasound

scholarly journals Basics for performing a high-quality color Doppler sonography of the vascular access

2021 ◽  
pp. 112972982110180
Author(s):  
Mario Meola ◽  
Jose Ibeas ◽  
Gianfranco Lasalle ◽  
Ilaria Petrucci
Keyword(s):  
Vascular Access ◽  
Pulse Repetition Frequency ◽  
Color Doppler ◽  
Random Noise ◽  
Doppler Frequency ◽  
Late Complications ◽  
Repetition Frequency ◽  
Pulse Repetition ◽  
Portable Ultrasound ◽  
Angle Correction

In the last years, the systematic use of ultrasound mapping of the upper limb vascular network before the arteriovenous fistula (AVF) implantation, access maturation, and clinical management of late complications is widespread and expanding. Therefore, a good knowledge of theoretical outlines, instrumentation, and operative settings is undoubtedly required for a thorough examination. In this review, the essential Doppler parameters, B-Mode setting, and Doppler applications are considered. Basic concepts on the Doppler shift equation, angle correction, settings on pulse repetition frequency, operative Doppler frequency, gain are reported to ensure adequate and correct sampling of blood flow velocity. A brief analysis of the Doppler inherent artefacts (as random noise, blooming, aliasing, and motion artefacts) and the adjustment setting to minimize or eliminate the confounding artefacts are also considered. Doppler aliasing occurs when the pulse repetition frequency is set too low. This artefact is particularly frequent in vascular access sampling due to the high velocities range registered in the fistula’s different segments. Aliasing should be recognized because its correction is crucial to analyse the Doppler signals correctly. Recent advances in instrumentation are also considered about a potential purchase of a portable ultrasound machine or a top-of-line, high-end, or mid-range ultrasound system. Last, the pulse wave Doppler setting for vascular access B-Mode and Doppler assessment is summarized.

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