Topic
Pulsatile flow
About: Pulsatile flow is a research topic. Over the lifetime, 6278 publications have been published within this topic receiving 149638 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: A two-dimensional numerical model was developed and it was disclosed that the non-Newtonian property of blood did not drastically change the flow patterns, but caused an appreciable increase in the shear stresses and a slightly higher resistance to both flow separations and the phase shifts between flow layers.
78 citations
TL;DR: This method should be useful for investigation of small animal models of ocular diseases as well as total blood flow measurements in human patients in the clinic, and is inherently less sensitive to involuntary eye motion.
Abstract: We present an approach to measure pulsatile total retinal arterial blood flow in humans and rats using ultrahigh speed Doppler OCT. The axial blood velocity is measured in an en face plane by raster scanning and the flow is calculated by integrating over the vessel area, without the need to measure the Doppler angle. By measuring flow at the central retinal artery, the scan area can be very small. Combined with ultrahigh speed, this approach enables high volume acquisition rates necessary for pulsatile total flow measurement without modification in the OCT system optics. A spectral domain OCT system at 840nm with an axial scan rate of 244kHz was used for this study. At 244kHz the nominal axial velocity range that could be measured without phase wrapping was ±37.7mm/s. By repeatedly scanning a small area centered at the central retinal artery with high volume acquisition rates, pulsatile flow characteristics, such as systolic, diastolic, and mean total flow values, were measured. Real-time Doppler C-scan preview is proposed as a guidance tool to enable quick and easy alignment necessary for large scale studies. Data processing for flow calculation can be entirely automatic using this approach because of the simple and robust algorithm. Due to the rapid volume acquisition rate and the fact that the measurement is independent of Doppler angle, this approach is inherently less sensitive to involuntary eye motion. This method should be useful for investigation of small animal models of ocular diseases as well as total blood flow measurements in human patients in the clinic.
78 citations
TL;DR: CNS-wide simulations of intrathecal drugs administration can become a practical tool for in silico design, interspecies scaling and optimization of experimental drug trials, and the feasibility of computational drug transport studies was demonstrated.
78 citations
Patent•
07 Sep 1976TL;DR: A portable hemodialysis system wherein blood and dialysate are pumped in the extracorporeal flow circuit by peristaltic compression of the blood and kidney flow lines to provide high frequency pulsatile flows in the respective fluid lines is described in this paper.
Abstract: A portable hemodialysis system wherein blood and dialysate are pumped in the extracorporeal flow circuit by peristaltic compression of the blood and dialysate flow lines to provide high frequency pulsatile flows in the respective fluid lines. The pulsatile flows of blood and dialysate are passed through the dialyzer to reduce fluid film mass transfer resistance therein and enhance the dialyzing efficiency of the hemodialysis system.
77 citations
TL;DR: It is suggested that lack of pulsatility may be one factor that has limited the success of continuous flow LVADs and research needs to focus on methods to generate pulsatility either by the native heart or by various speed modulation algorithms.
Abstract: Despite significant improved survival with continuous flow left ventricular assist devices (LVADs), complications related to aortic valve insufficiency, gastrointestinal bleeding, stroke, pump thrombosis, and hemolysis have dampened the long term success of these pumps. Evolution has favored a pulsatile heart pump to be able to deliver the maximum flow at different levels of systemic vascular resistance, confer kinetic energy to the flow of blood past areas of stenosis and generate low shear stress on blood elements. In this perspective, we suggest that lack of pulsatility may be one factor that has limited the success of continuous flow LVADs and suggest that research needs to focus on methods to generate pulsatility either by the native heart or by various speed modulation algorithms.
77 citations