Quantitative morphologic study of intimal thickening at the human carotid bifurcation: I. Axial and circumferential distribution of maximum intimal thickening in asymptomatic, uncomplicated plaques

1994 ◽  
Vol 107 (2) ◽  
pp. 137-146 ◽  
Author(s):  
Nobuhide Masawa ◽  
Seymour Glagov ◽  
Christopher K. Zarins
Keyword(s):  
Carotid Bifurcation ◽  
Intimal Thickening ◽  
Morphologic Study ◽  
Circumferential Distribution ◽  
Human Carotid

Morphological Study of Carotid Artery of WHHL Rabbit after Balloon Dilatation

1998 ◽  
Vol 4 (1_suppl) ◽  
pp. 183-186
Author(s):  
T. Yokouchi ◽  
S. Iwabuchi ◽  
A. Tomiyama ◽  
H. Samejima ◽  
K. Takahashi ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Carotid Artery ◽  
Morphological Study ◽  
Balloon Dilatation ◽  
Carotid Bifurcation ◽  
Morphological Alteration ◽  
Elastic Fibers ◽  
Intimal Thickening ◽  
The Media ◽  
Over Time

We performed balloon dilatation in the carotid artery of WHHL rabbits and examined subsequent morphological alteration over time. The balloon was inserted as far as the carotid bifurcation and observations were made on the morphological alteration after dilatation in the atherosclerotic intimal thickening from immediately after balloon dilatation over a period of ten months. Immediately after balloon dilatation, endothelial cells came of circularly and stretching, fragmentation off elastic fibers and coming off of smooth muscle cells of the media were confirmed. No change in the degree of thickening after dilatation was seen in the atherosclerotic intimal thickening of the carotid bifurcation. Three weeks later, endothelium covering except some parts, circular neointima and fibrosis of the media were observed; foamy cells had accumulated in the upper layer of the atherosclerotic intimal thickening, and that region was not yet covered with endothelial cells. The progress of fibrous intimal thickening so as to keep the lumen smooth was seen up to six months later, but foamy cells were not found in the neointima.

Flow and Atherogenesis in the Human Carotid Bifurcation

1983 ◽  
pp. 38-45 ◽  
Author(s):  
D. P. Giddens ◽  
C. K. Zarins ◽  
S. Glagov ◽  
B. K. Bharadvaj ◽  
D. N. Ku
Keyword(s):  
Carotid Bifurcation ◽  
Human Carotid

Targeted Particle Tracking in Computational Models of Human Carotid Bifurcations

2011 ◽  
Vol 133 (12) ◽  
Author(s):  
Ian Marshall
Keyword(s):  
Healthy Volunteer ◽  
Carotid Artery ◽  
Flow Region ◽  
Carotid Bifurcation ◽  
Flow Patterns ◽  
External Carotid ◽  
Complex Flow ◽  
Imaging Science ◽  
Carotid Bulb ◽  
Human Carotid

A significant and largely unsolved problem of computational fluid dynamics (CFD) simulation of flow in anatomically relevant geometries is that very few calculated pathlines pass through regions of complex flow. This in turn limits the ability of CFD-based simulations of imaging techniques (such as MRI) to correctly predict in vivo performance. In this work, I present two methods designed to overcome this filling problem, firstly, by releasing additional particles from areas of the flow inlet that lead directly to the complex flow region (“preferential seeding”) and, secondly, by tracking particles both “downstream” and “upstream” from seed points within the complex flow region itself. I use the human carotid bifurcation as an example of complex blood flow that is of great clinical interest. Both idealized and healthy volunteer geometries are investigated. With uniform seeding in the inlet plane (in the common carotid artery (CCA)) of an idealized bifurcation geometry, approximately half the particles passed through the internal carotid artery (ICA) and half through the external carotid artery. However, of those particles entering the ICA, only 16% passed directly through the carotid bulb region. Preferential seeding from selected regions of the CCA was able to increase this figure to 47%. In the second method, seeding of particles within the carotid bulb region itself led to a very high proportion (97%) of pathlines running from CCA to ICA. Seeding of particles in the bulb plane of three healthy volunteer carotid bifurcation geometries led to much better filling of the bulb regions than by particles seeded at the inlet alone. In all cases, visualization of the origin and behavior of recirculating particles led to useful insights into the complex flow patterns. Both seeding methods produced significant improvements in filling the carotid bulb region with particle tracks compared with uniform seeding at the inlet and led to an improved understanding of the complex flow patterns. The methods described may be combined and are generally applicable to CFD studies of fluid and gas flow and are, therefore, of relevance in hemodynamics, respiratory mechanics, and medical imaging science.

Relation between histological age-changes in the carotid body and atherosclerosis in the carotid arteries

1987 ◽  
Vol 101 (12) ◽  
pp. 1271-1275 ◽  
Author(s):  
Patrick Lowe ◽  
Donald Heath ◽  
Paul Smith
Keyword(s):  
Blood Flow ◽  
Carotid Body ◽  
Carotid Arteries ◽  
Carotid Sinus ◽  
Carotid Bifurcation ◽  
Age Changes ◽  
Histological Changes ◽  
Atherosclerotic Lesions ◽  
Flow Through ◽  
Human Carotid

Abstract Histological changes in the human carotid body associated with increasing age are accompanied by occlusive atherosclerotic lesions in the arteries of the carotid bifurcation, and are probably ischaemic in origin. The carotid sinus, however, is unusually susceptible to the development of atheroma and its occlusion appears to have little influence in compromising blood flow through the glomic arteries.

Mixing in the Human Carotid Artery during Carotid Drug Infusion Studied with PET

1989 ◽  
Vol 9 (5) ◽  
pp. 681-689 ◽  
Author(s):  
Larry Junck ◽  
Robert A. Koeppe ◽  
Harry S. Greenberg
Keyword(s):  
Carotid Artery ◽  
Carotid Bifurcation ◽  
Drug Infusion ◽  
Arterial Infusion ◽  
Positron Emission ◽  
Volume Of Interest ◽  
Wide Range ◽  
Vinyl Tube ◽  
Catheter Tip ◽  
Human Carotid

The safety and efficacy of drug infusion into the carotid artery require adequate mixing of the infused solution with carotid blood. Using positron emission tomography (PET), we studied the mixing of solutions infused into the human carotid artery in seven patients by analyzing the distribution of [15O]H2O infused into the carotid artery and by vein. At four infusion rates ranging from 0.5 to 10 ml/min, the variability in distribution averaged 16.5–17.8% among the pixels in a large volume of interest, without dependence on the infusion rate. The overall correlation between [15O]H2O influx with arterial infusion and [15O]H2O influx with venous injection was 0.78–0.82 at the four infusion rates, with no trend toward higher correlations at the faster infusion rates. The distribution into the anterior, middle, and posterior cerebral artery territories differed from distribution throughout the entire carotid territory by an average of 6.2–9.6% at the four infusion rates, with no trend toward smaller differences at the faster infusion rates. Infusions performed into a vinyl tube simulating the carotid artery indicated that at 0.5 ml/min, the velocity of fluid exiting the catheter makes no apparent contribution to mixing. We conclude that with infusions at the carotid bifurcation, mixing in the human carotid artery is complete or nearly complete over a wide range of infusion rates. The mixing appears to result from the patterns of blood flow within the artery, and not from jet effects at the catheter tip.

scholarly journals Reconstruction of blood flow patterns in a human carotid bifurcation: A combined CFD and MRI study

2000 ◽  
Vol 11 (3) ◽  
pp. 299-311 ◽  
Author(s):  
Quan Long ◽  
X. Yun Xu ◽  
Ben Ariff ◽  
Simon A. Thom ◽  
Alun D. Hughes ◽  
...  
Keyword(s):  
Blood Flow ◽  
Carotid Bifurcation ◽  
Flow Patterns ◽  
Mri Study ◽  
Blood Flow Patterns ◽  
Human Carotid

Sensitivity of Hemodynamic Parameters to Waveform, Flow Division, and Head Rotation in the Human Carotid Bifurcation

2008 ◽  
Author(s):  
Yannis Papaharilaou ◽  
Ioannis Seimenis ◽  
John Ekaterinaris ◽  
Georgios Georgiou ◽  
Eleni Eracleous ◽  
...  
Keyword(s):  
Shear Stress ◽  
Wall Shear Stress ◽  
Head Rotation ◽  
Carotid Bifurcation ◽  
Hemodynamic Parameters ◽  
Flow Waveform ◽  
Temporal Gradient ◽  
Wall Shear ◽  
Flow Division ◽  
Human Carotid

Hemodynamic parameters such as time averaged wall shear stress (TAWSS), wall shear stress temporal gradient (WSSTG) and Oscillatory Shear Index (OSI) have previously been cited as parameters associated with the development of atherosclerotic disease at the human carotid bifurcation [1,2]. The sensitivity of these important parameters however, with variations of driving flow waveform, flow division and posture changes are not well known. To investigate these changes, we have used image based CFD, to analyze the flowfield of the carotid bifurcation of a healthy volunteer for five different input waveforms, three flow division ratios and two head postures.

Age-Dependent Morphological Changes of the Human Carotid Bifurcation

1999 ◽  
Author(s):  
Baruch B. Lieber ◽  
Ajay K. Wakhloo ◽  
Andreas R. Luft ◽  
Afshin A. Divani
Keyword(s):  
Blood Flow ◽  
Blood Supply ◽  
Carotid Sinus ◽  
Subsequent Development ◽  
Carotid Bifurcation ◽  
Support Pressure ◽  
Morphological Development ◽  
Sinus Wall ◽  
The Brain ◽  
Human Carotid

Abstract The development, significance and function of the human carotid sinus is not yet well understood. The arterial wall within the carotid sinus is well enervated and it contains baroreceptive neural terminals. One hypothesis that was put forward is that the dilation, which may involve all vessels of the carotid bifurcation, exists to support pressure sensing1. Another hypothesis that is supported only by phenomenological observations assume that the function of the sinus is to protect the brain by slowing blood flow and reducing pulsatility2. Yet another hypothesis interprets the sinus as an ontogenetic or phylogenic residual3. More recently, carotid hemodynamics has been investigated using in vitro and computational models. Flow patterns in the carotid sinus were found to be complex and as such have been implicated in the hetrogenesis and subsequent development of atherosclerosis at this site. However, the development of this unique sinus morphology, the role of hemodynamics in such development, and the physiological implications created by this unique morphology have not been investigated. Understanding the hemodynamic and developmental forces that play a role in remodeling of the carotid bifurcation and development of the sinus is of both fundamental and clinical interest and can lead to better prognostication and therapy of carotid disease. Therefore, we initiated a study of the morphological development of the human carotid bulb using different age groups under the hypothesis that sinus morphology reflects an adaptive change in response to alterations in cerebral blood supply during the developmental years of the brain. This adaptation attempts to reduce hydraulic losses in the carotid bifurcation through reduced flow disturbances and maintain high level of blood supply to the brain than consumes about 15% of cardiac output under basal conditions. In addition, it may protect the sinus wall from high shear stress and/or the brain from highly pulsatile blood flow conditions. Initially, we analyzed the angle and sinus morphology of the carotid bifurcation in pediatric and adult patients using biplane digital subtraction angiograms to characterize changes that occur as the brain matures.

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