Methods to measure blood flow velocity of red blood cells in vivo at the microscopic level

1986 ◽  
Vol 14 (2) ◽  
pp. 175-186 ◽  
Author(s):  
Dick W. Slaaf ◽  
Theo J. M. Jeurens ◽  
Geert Jan Tangelder ◽  
Robert S. Reneman ◽  
Theo Arts
1980 ◽  
Vol 238 (5) ◽  
pp. H745-H749 ◽  
Author(s):  
C. H. Baker ◽  
E. T. Sutton ◽  
D. L. Davis

An indicator dilution technique is described for obtaining time-concentration curves subsequent to bolus injections of sulfhemoglobin red blood cells (SH-RBC), which have a deep greenish-brown color (absorption peak 620 nm vs. 542 and 564 nm for normal red cells). The series- and parallel-coupled microvessels of cat mesentery were studied. This is accomplished by means of video microscopy with a two-window intensity-sensitive video sampler system. The relationship between SH-RBC concentration in blood and optical measurement is linear. Blood flow velocities were calculated from the difference in mean transit times between two points along a vessel. When this technique is used in association with the previously reported method for determining time-concentration curves for the plasma indicator FITC-dextran the mean transit time (t) for red blood cells was less than for plasma in arterioles. The reproducibility of t and flow velocity for both SH-RBC and FITC-dextran from successive injections were reported. The mean transit time ratio of arteriolar SH-RBC to FITC-dextran averages 0.89. Blood flow velocity calculated from SH-RBC is greater than that calculated from FITC-dextran in these same arterioles. The ratio of the velocities averages 1.29.


2020 ◽  
Vol 61 (6) ◽  
pp. 188-200
Author(s):  
Malte Schroeder ◽  
Lennart Viezens ◽  
Jördis Sündermann ◽  
Svenja Hettenhausen ◽  
Gerrit Hauenherm ◽  
...  

Introduction: Prostate cancer has a special predilection to form bone metastases. Despite the known impact of the microvascular network on tumour growth and its dependence on the organ-specific microenvironment, the characteristics of the tumour vasculature in bone remain unknown. Methods: The cell lines LNCaP, DU145, and PC3 were implanted into the femurs of NSG mice to examine the microvascular properties of prostate cancer in bone. Tumour growth and the functional and morphological alterations of the microvasculature were analysed for 21 days in vivo using a transparent bone chamber and fluorescence microscopy. Results: Vascular density was significantly lower in tumour-bearing bone than in non-tumour-bearing bone, with a marked loss of small vessels. Accelerated blood flow velocity led to increased volumetric blood flow per vessel, but overall perfusion was not affected. All of the prostate cancer cell lines had similar vascular patterns, with more pronounced alterations in rapidly growing tumours. Despite minor differences between the prostate cancer cell lines associated with individual growth behaviours, the same overall pattern was observed and showed strong similarity to that of tumours growing in soft tissue. Discussion: The increase in blood flow velocity could be a specific characteristic of prostate cancer or the bone microenvironment.


1997 ◽  
Vol 22 (14) ◽  
pp. 1119 ◽  
Author(s):  
Zhongping Chen ◽  
Thomas E. Milner ◽  
Shyam Srinivas ◽  
Xiaojun Wang ◽  
Arash Malekafzali ◽  
...  

Neurosurgery ◽  
2010 ◽  
Vol 66 (6) ◽  
pp. 1050-1057 ◽  
Author(s):  
Anders Behrens ◽  
Niklas Lenfeldt ◽  
Khalid Ambarki ◽  
Jan Malm ◽  
Anders Eklund ◽  
...  

Abstract BACKGROUND Transcranial Doppler sonography (TCD) assessment of intracranial blood flow velocity has been suggested to accurately determine intracranial pressure (ICP). OBJECTIVE We attempted to validate this method in patients with communicating cerebrospinal fluid systems using predetermined pressure levels. METHODS Ten patients underwent a lumbar infusion test, applying 4 to 5 preset ICP levels. On each level, the pulsatility index (PI) in the middle cerebral artery was determined by measuring the blood flow velocity using TCD. ICP was simultaneously measured with an intraparenchymal sensor. ICP and PI were compared using correlation analysis. For further understanding of the ICP-PI relationship, a mathematical model of the intracranial dynamics was simulated using a computer. RESULTS The ICP-PI regression equation was based on data from 8 patients. For 2 patients, no audible Doppler signal was obtained. The equation was ICP = 23*PI + 14 (R2 = 0.22, P < .01, N = 35). The 95% confidence interval for a mean ICP of 20 mm Hg was −3.8 to 43.8 mm Hg. Individually, the regression coefficients varied from 42 to 90 and the offsets from −32 to +3. The mathematical simulations suggest that variations in vessel compliance, autoregulation, and arterial pressure have a serious effect on the ICP-PI relationship. CONCLUSIONS The in vivo results show that PI is not a reliable predictor of ICP. Mathematical simulations indicate that this is caused by variations in physiological parameters.


Author(s):  
Hideyuki Hasegawa ◽  
Michiya Mozumi ◽  
Masaaki Omura ◽  
Ryo Nagaoka ◽  
Kozue Saito

Abstract High-frame-rate ultrasound imaging with plane wave transmissions is a predominant method for blood flow imaging, and methods for estimation of blood flow velocity vectors have been developed based on high-frame-rate imaging. On the other hand, in imaging of soft tissues, such as arterial walls and atherosclerotic plaques, high-frame-rate imaging sometimes suffers from high-level clutters. Even in observation of the arterial wall with a focused transmit beam, it would be highly beneficial if blood flow velocity vectors could be estimated simultaneously. We conducted a preliminary study on estimation of blood flow velocity vectors based on a multi-angle Doppler method with focused transmit beam and parallel receive beamforming. It was shown that the lowest estimation error was achieved at a steering angle of 25 degrees by simulation. Also, velocity vectors with typical velocity magnitudes and directions could be obtained by the proposed method in in vivo measurement of a carotid artery.


2016 ◽  
Vol 120 (8) ◽  
pp. 084701 ◽  
Author(s):  
Tomoaki Kyoden ◽  
Shoji Naruki ◽  
Shunsuke Akiguchi ◽  
Hiroki Ishida ◽  
Tsugunobu Andoh ◽  
...  

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