In vivo comparison of atherosclerotic plaque progression with vessel wall strain and blood flow velocity in apoE−/− mice with MR microscopy at 17.6 T

2009 ◽  
Vol 22 (3) ◽  
pp. 159-166 ◽  
Author(s):  
Volker Herold ◽  
Jeremy Wellen ◽  
Christian H. Ziener ◽  
Thomas Weber ◽  
Karl-Heinz Hiller ◽  
...  
Keyword(s):  
Blood Flow ◽  
Flow Velocity ◽  
Atherosclerotic Plaque ◽  
Blood Flow Velocity ◽  
Vessel Wall ◽  
Plaque Progression ◽  
Mr Microscopy

Preclinical Quantification of Prostate Cancer-Associated Vascular Alterations in the Bone Microenvironment in vivo

2020 ◽  
Vol 61 (6) ◽  
pp. 188-200
Author(s):  
Malte Schroeder ◽  
Lennart Viezens ◽  
Jördis Sündermann ◽  
Svenja Hettenhausen ◽  
Gerrit Hauenherm ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Blood Flow ◽  
Flow Velocity ◽  
Cell Lines ◽  
Blood Flow Velocity ◽  
Tumour Growth ◽  
Prostate Cancer Cell ◽  
Bone Microenvironment ◽  
Prostate Cancer Cell Lines

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.

Human Carotid Atherosclerotic Plaque Growth Function and Progression Simulation Using Meshless GFD and Statistical Methods Based on Multi-Year In Vivo MRI

2008 ◽  
Author(s):  
Chun Yang ◽  
Joseph D. Petruccelli ◽  
Zhongzhao Teng ◽  
Chun Yuan ◽  
Gador Canton ◽  
...  
Keyword(s):  
Atherosclerotic Plaque ◽  
Wall Thickness ◽  
Vessel Wall ◽  
Plaque Rupture ◽  
Patient Specific ◽  
Tracking Data ◽  
Plaque Progression ◽  
Vessel Wall Thickness ◽  
Plaque Growth

Atherosclerotic plaque rupture and progression have been the focus of intensive investigations in recent years. The mechanisms governing plaque progression and rupture process are not well understood. Using computational models based on patient-specific multi-year in vivo MRI data, our recent results indicated that 18 out of 21 patients studied showed significant negative correlation between plaque progression measured by vessel wall thickness increase (WTI) and plaque wall (structural) stress (PWS) [1]. In this paper, a computational procedure based on meshless generalized finite difference (MGFD) method and serial magnetic resonance imaging (MRI) data was introduced to simulate plaque progression. Participating patients were scanned three times (T1, T2, and T3, at intervals of approximately 18 months) to obtain plaque progression data. Vessel wall thickness (WT) changes were used as the measure for plaque progression. Starting from T2 plaque geometry, plaque progression was simulated by solving the solid model and adjusting wall thickness using plaque growth functions iteratively until time T3 is reached. Numerically simulated plaque progression showed very good agreement with actual plaque geometry at T3 given by MRI data. We believe this is the first time plaque progression simulation results based on multi-year patient-tracking data are reported. Multi-year tracking data and MRI-based progression simulation add time dimension to plaque vulnerability assessment and will improve prediction accuracy.

scholarly journals Noninvasive imaging of in vivo blood flow velocity using optical Doppler tomography

1997 ◽  
Vol 22 (14) ◽  
pp. 1119 ◽  
Author(s):  
Zhongping Chen ◽  
Thomas E. Milner ◽  
Shyam Srinivas ◽  
Xiaojun Wang ◽  
Arash Malekafzali ◽  
...  
Keyword(s):  
Blood Flow ◽  
Flow Velocity ◽  
Blood Flow Velocity ◽  
Noninvasive Imaging ◽  
Doppler Tomography ◽  
Optical Doppler Tomography

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
Keyword(s):  
Blood Flow ◽  
Red Blood Cells ◽  
Flow Velocity ◽  
Blood Flow Velocity ◽  
Blood Cells ◽  
Microscopic Level ◽  
Measure Blood Flow

Transcranial Doppler Pulsatility Index: Not an Accurate Method to Assess Intracranial Pressure

Neurosurgery ◽  
2010 ◽  
Vol 66 (6) ◽  
pp. 1050-1057 ◽  
Author(s):  
Anders Behrens ◽  
Niklas Lenfeldt ◽  
Khalid Ambarki ◽  
Jan Malm ◽  
Anders Eklund ◽  
...  
Keyword(s):  
Blood Flow ◽  
Intracranial Pressure ◽  
Flow Velocity ◽  
Transcranial Doppler ◽  
Blood Flow Velocity ◽  
Pulsatility Index ◽  
Transcranial Doppler Sonography ◽  
Accurate Method ◽  
Mathematical Simulations

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.

Preliminary study on estimation of flow velocity vectors using focused transmit beams

2021 ◽  
Author(s):  
Hideyuki Hasegawa ◽  
Michiya Mozumi ◽  
Masaaki Omura ◽  
Ryo Nagaoka ◽  
Kozue Saito
Keyword(s):  
Blood Flow ◽  
Flow Velocity ◽  
Blood Flow Velocity ◽  
Soft Tissues ◽  
Estimation Error ◽  
Frame Rate ◽  
High Frame Rate ◽  
In Vivo Measurement ◽  
Preliminary Study

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.

In vivo visualization method by absolute blood flow velocity based on speckle and fringe pattern using two-beam multipoint laser Doppler velocimetry

2016 ◽  
Vol 120 (8) ◽  
pp. 084701 ◽  
Author(s):  
Tomoaki Kyoden ◽  
Shoji Naruki ◽  
Shunsuke Akiguchi ◽  
Hiroki Ishida ◽  
Tsugunobu Andoh ◽  
...  
Keyword(s):  
Blood Flow ◽  
Flow Velocity ◽  
Blood Flow Velocity ◽  
Laser Doppler Velocimetry ◽  
Fringe Pattern ◽  
Laser Doppler ◽  
Doppler Velocimetry ◽  
Visualization Method
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