<title>Improved determination of vascular blood-flow shear rate using Doppler ultrasound</title>

AbstractHemorrhage is the phenomenon of blood loss caused by vascular trauma or other pathological reasons, which is life-threatening in severe cases. Because microhemorrhage is difficult to visually monitor and pre-treat in vivo, it is necessary to establish in vitro prediction methods to study the hemostasis mechanism in different physiological environments. In this study, a microfluidic bleeding model was developed to investigate the effect of blood flow shear on microvascular hemostasis. The results indicated that the regulation of blood shear rate on platelet aggregation affected the growth and morphology of hemostatic thrombus, and finally regulated the process of hemostasis. This in vitro model is significant to studies on hemostatic mechanisms, a reliable prediction of microhemorrhages, and an adjustment of the treatment scheme.

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Determination of coronary artery blood flow shear rates based on Doppler catheter recordings

Journal of the American College of Cardiology ◽

10.1016/0735-1097(91)91156-9 ◽

1991 ◽

Vol 17 (2) ◽

pp. A47

Author(s):

Scott J. Denardo ◽

Paul G. Yock ◽

Victor K. Hargrave ◽

James P. Srebro ◽

Thomas A. Ports ◽

...

Keyword(s):

Blood Flow ◽

Coronary Artery ◽

Artery Blood Flow ◽

Flow Shear ◽

Shear Rates

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On the significance of blood flow shear-rate-dependency in modeling of Fontan hemodynamics

European Journal of Mechanics - B/Fluids ◽

10.1016/j.euromechflu.2020.05.011 ◽

2020 ◽

Vol 84 ◽

pp. 1-14

Author(s):

Heng Wei ◽

Andrew L. Cheng ◽

Niema M. Pahlevan

Keyword(s):

Blood Flow ◽

Shear Rate ◽

Rate Dependency ◽

Flow Shear

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Assessment of the incorporation of revascularized fibula grafts used for mandibular reconstruction with F-18-PET

Nuklearmedizin ◽

10.1055/s-0038-1623992 ◽

2001 ◽

Vol 40 (02) ◽

pp. 51-58 ◽

Cited By ~ 12

Author(s):

H. Schliephake ◽

van den Hoff ◽

W. H. Knapp ◽

G. Berding

Keyword(s):

Blood Flow ◽

Regional Blood Flow ◽

Venous Blood ◽

Mandibular Reconstruction ◽

Reference Region ◽

Osteoblastic Activity ◽

Non Union ◽

Range Of Values ◽

Measured Input

Summary Aim: Determination of the range of regional blood flow and fluoride influx during normal incorporation of revascularized fibula grafts used for mandibular reconstruction. Evaluation, if healing complications are preceded by typical deviations of these parameters from the normal range. Assessment of the potential influence of using “scaled population-derived” instead of “individually measured” input functions in quantitative analysis. Methods: Dynamic F-l 8-PET images and arterialized venous blood samples were obtained in 11 patients early and late after surgery. Based on kinetic modeling regional blood flow (K1) and fluoride influx (Kmlf) were determined. Results: In uncomplicated cases, early postoperative graft K1 - but not Kmlf -exceeded that of vertebrae as reference region. Kmn values obtained in graft necrosis (n = 2) were below the ranges of values observed in uncomplicated healing (0.01 13-0.0745 ml/min/ml) as well as that of the reference region (0.0154-0.0748). Knf values in mobile non-union were in the lower range - and those in rigid non-union in the upper range of values obtained in stable union (0.021 1-0.0694). If scaled population-derived instead of measured input functions were used for quantification, mean deviations of 23 ± 17% in K1 and 12 ± 16% in Kmlf were observed. Conclusions: Normal healing of predominantly cortical bone transplants is characterized by relatively low osteoblastic activity together with increased perfusion. It may be anticipated that transplant necrosis can be identified by showing markedly reduced F− influx. In case that measured input functions are not available, quantification with scaled population-derived input functions is appropriate if expected differences in quantitative parameters exceed 70%.

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