Extensive flow studies are conducted in two carotid bifurcation flow phantoms. These phantoms exactly replicate the lumen of the plaque excised intact from two patients with severe carotid atherosclerosis. The input flow into the phantom’s common carotid artery is steady. Novel scanning techniques for flow visualization and particle image velocimetry are used. In addition, a novel boundary treatment technique is employed in velocimetry to extract first order accurate velocity gradients at walls. The data show that the flow fields are highly three-dimensional. Numerous separation and recirculation zones dominate the flow domain, except at the lowest Reynolds numbers. The separation regions are often so severe that highly directed internal jets form. At high Reynolds numbers, the flows become unsteady and chaotic, even though the input flow is steady. Flow fields have large regions of energetic flow and almost stagnant recirculation zones. These recirculation zones range in size from the full size of the arteries to zones within crevasses smaller than 1 mm. Velocity field and streamline patterns conform well to the lumen geometry. The streamlines are highly tortuous. Stagnation points correlate well with the topological features of the stenosis. Vorticity maps confirm the highly complex and three dimensional nature of the flow. Wall shear stresses at the stenoses are estimated to be on the order of 10 Pa. These studies conclusively show that the nature of the flow in the diseased bifurcation is primarily dictated by the lumen geometry.

1.
Jorgensen
,
L.
, and
Torvik
,
A.
,
1969
, “
Ischaemic Cerebrovascular Diseases in an Autopsy Series
,”
J. Neurol. Sci.
,
9
, pp.
285
320
.
2.
Nicholls
,
S.
,
Kohler
,
T.
,
Bergelin
,
R.
,
Primozich
,
J.
,
Lawrence
,
R.
, and
Strandness
,
D.
,
1986
, “
Carotid Artery Occlusion
,”
J. Vasc. Surg.
,
4
, pp.
479
485
.
3.
Timsit
,
S. G.
,
Sacco
,
R. L.
,
Mohr
,
J. P.
,
Foulkes
,
M. A.
,
Tatemichi
,
T. K.
,
Wolf
,
P. A.
,
Price
,
T. R.
, and
Hier
,
D. B.
,
1992
, “
Early Clinical Differentiation of Cerebral Infarction from Severe Atherosclerotic Stenosis and Cardioembolism
,”
Stroke
,
23
, pp.
486
491
.
4.
Fuster
,
V.
,
Stein
,
B.
,
Ambrose
,
J. A.
,
Badimon
,
L.
, and
Chesebro
,
J. H.
,
1990
, “
Atherosclerotic Plaque Rupture and Thrombosis. Evolving Concepts
,”
Circulation
,
82
, pp.
1147
1159
.
5.
ACAS
,
1995
, “
Endarterectomy for Asymptotic Carotid Artery Stenosis
,” Executive Committee for the Asymptotic Carotid Atherosclerosis Study.
JAMA, J. Am. Med. Assoc.
,
273
, pp.
1421
1428
.
6.
ECSTC
,
1991
, “
MRC European Carotid Surgery Trial: Interim Results for Symptomatic Patients with Severe (70–99%) or with Mild (0–29%) Carotid Stenosis
,” Group ECSTC,
Lancet
,
337
, pp.
1235
1243
.
7.
Nerem, R. M., 1995, “Atherosclerosis and the Role of Wall Shear Stress,” Flow-Dependent Regulation of Vascular Function, Bevan, J. A., Kaley, G., and Rubanyi, G. M., eds., Oxford University Press, New York, NY, pp. 300–319.
8.
Libby
,
P.
,
1995
, “
Lesion versus Lumen
,”
Nat. Med.
,
1
, pp.
17
18
.
9.
Gimbrone
, Jr,
M. A.
,
Resnick
,
N.
,
Nagel
,
T.
,
Khachigian
,
L. M.
,
Collins
,
T.
, and
Topper
,
J. N.
,
1997
, “
Hemodynamics, Endothelial Gene Expression, and Atherogenesis
,”
Ann. N.Y. Acad. Sci.
,
811
, pp.
1
11
.
10.
Berger
,
S. A.
, and
Jou
,
L.-D.
,
2000
, “
Flows in Stenotic Vessels
,”
Annu. Rev. Fluid Mech.
,
32
, pp.
347
382
.
11.
Stroud
,
J. S.
,
Berger
,
S. A.
, and
Saloner
,
D.
,
2000
, “
Influence of Stenosis Morphology on Flow Through Severely Stenotic Vessels: Implications for Plaque Rapture
,”
J. Biomech.
,
33
, pp.
443
455
.
12.
Caro
,
C. G.
,
Fitzgerald
,
J. M.
, and
Schroter
,
R. C.
,
1971
, “
Atheroma and Arterial Wall Shear Observations, Correlation and Proposal of a Shear Dependent Mass Transfer Mechanism for Atherogenesis
,”
Proc. R. Soc. London
,
17
, pp.
109
159
.
13.
Glagov, S., Zarin, C. K., Giddens, D. P., and Ku, D. N., 1989, “Mechanical Factors in the Pathogenesis, Localization and Evolution of Atherosclerotic Plaques,” Diseases of the Artery Wall, Camillen, J. P., Berny, C. L., Fiessinger, J. N., and Bariety, J., eds., Springer-Verlag, New York, NY, pp. 217–239.
14.
Beach
,
K. W.
,
Hatsukami
,
T.
,
Detmer
,
P. R.
,
Primozich
,
J. F.
,
Ferguson
,
M. S.
,
Gordon
,
D.
,
Alpers
,
C. E.
,
Burns
,
D. H.
,
Thackray
,
B. D.
, and
Strandness
,
D. E.
,
1993
, “
Carotid Artery Intraplaque Hemorrhage and Stenotic Velocity
,”
Stroke
,
24
, pp.
314
319
.
15.
Consigny
,
P.
,
1995
, “
Pathogenesis of Atherosclerosis
,”
Am. J. Roentgenol.
,
164
, pp.
553
558
.
16.
Slack
,
S. M.
,
Cui
,
Y.
, and
Turittto
,
V. T.
,
1993
, “
The Effects of Flow on Blood Coagulation and Thrombosis
,”
Thromb Haemost
,
70
, pp.
129
134
.
17.
Affeld
,
K.
,
Reininger
,
A. J.
,
Gadischke
,
J.
,
Grunert
,
K.
,
Schmidt
,
S.
, and
Thiele
,
F.
,
1995
, “
Fluid Mechanics of the Stagnation Point Flow Chamber and its Platelet Deposition
,”
Artif. Organs
,
19
, pp.
597
602
.
18.
Bharadvaj
,
B. K.
,
Mabon
,
R. F.
, and
Giddens
,
D. P.
,
1982
, “
Steady Flow in a Model of the Human Harotid Bifurcation. Part I—Flow Visualization; Part II—Laser-Doppler Anemometer Measurements
,”
J. Biomech.
,
15
, pp.
349
378
.
19.
Motomiya
,
M.
, and
Karino
,
T.
,
1984
, “
Flow Patterns in the Human Carotid Artery Bifurcation
,”
Stroke
,
15
, pp.
50
56
.
20.
Kerber
,
C. W.
, and
Heilman
,
C. B.
,
1992
, “
Flow Dynamics in the Human Carotid Artery: I. Preliminary Observations Using a Transparent Elastic Model
,”
AJNR Am. J. Neuroradiol.
,
13
, pp.
173
180
.
21.
Ku
,
D. N.
, and
Giddens
,
D. P.
,
1983
, “
Pulsatile Flow in a Model Carotid Bifurcation
,”
Arteriosclerosis (Dallas)
,
3
, pp.
31
39
.
22.
LoGerfo
,
F. W.
,
Nowak
,
M. D.
, and
Quist
,
W. C.
,
1985
, “
Structural Details of Boundary Layer Separation in a Model Human Carotid Bifurcation Under Steady and Pulsatile Flow Conditions
,”
J. Vasc. Surg.
,
2
, pp.
263
269
.
23.
Rindt
,
C. C.
, and
Steenhoven
,
A. A.
,
1996
, “
Unsteady Flow in a Rigid 3-D Model of the Carotid Artery Bifurcation
,”
J. Biomech. Eng.
,
118
, pp.
90
96
.
24.
Ku
,
D. N.
, and
Giddens
,
D. P.
,
1987
, “
Laser Doppler Anemometer Measurements of Pulsatile Flow in a Model Carotid Bifurcation
,”
J. Biomech.
,
20
, pp.
407
421
.
25.
Samuel
,
K. C.
,
1956
, “
Atherosclerosis and Occlusion of the Internal Carotid Artery
,”
J. Pathol. Bacteriol.
,
71
, pp.
391
401
.
26.
Solberg
,
L. A.
, and
Eggen
,
D. A.
,
1971
, “
Localization and Sequence of Development of Atherosclerotic Lesions in the Carotid and Vertebral Arteries
,”
Circulation
,
43
, pp.
711
724
.
27.
Polak
,
J. F.
,
O’Leary
,
D. H.
,
Quist
,
W. C.
,
Creager
,
M. A.
, and
LoGerfo
,
F. W.
,
1990
, “
Pulsed and Color Doppler Analysis of Normal Carotid Bifurcation Flow Dynamics using an In-vitro Model
,”
Angiology
,
41
, pp.
241
247
.
28.
Palmen
,
D. E.
,
van de Vosse
,
F. N.
,
Janssen
,
J. D.
, and
van Dongen
,
M. E.
,
1994
, “
Analysis of the Flow in Stenosed Carotid Artery Bifurcation Models—Hydrogen-Bubble Visualization
,”
J. Biomech.
,
27
, pp.
581
590
.
29.
Gijsen
,
F. J. H.
,
Palmen
,
D. E. M.
,
van der Beek
,
M. H. E.
,
van de Vosse
,
F. N.
,
van Dongen
,
M. E. H.
, and
Janssen
,
J. D.
,
1996
, “
Analysis of the Axial Flow Field in Stenosed Carotid Artery Bifurcation Models—LDA Experiments
,”
J. Biomech.
,
29
, pp.
1483
1489
.
30.
Pan
,
X.
,
Saloner
,
D.
,
Reilly
,
L. M.
,
Bowersox
,
J. C.
,
Murray
,
S. P.
,
Anderson
,
C. M.
,
Gooding
,
G. A. W.
, and
Rapp
,
J. H.
,
1995
, “
Assessment of Carotid Artery Stenosis by Ultrasonography, Conventional Angiography, and Magnetic Resonance Angiography: Correlation with Ex-vivo Measurement of the Plaque Stenosis
,”
J. Vasc. Surg.
,
21
(
1
), pp.
82
89
.
31.
Adrian
,
R.
,
1991
, “
Particle-Imaging Techniques for Experimental Fluid Mechanics
,”
Annu. Rev. Fluid Mech.
,
23
, pp.
261
304
.
32.
Sholl, M., and Savas¸, O¨., 1997, “A Fast Lagrangian PIV Method for Study of General High-Gradient Flows,” AIAA Paper No. 97-0493. AIAA, Reston, VA.
33.
Tsuei
,
L.
, and
Savas¸
,
O¨.
,
2000
, “
Treatment of Interfaces in Particle Image Velocimetry
,”
Experiments in Fluids
,
29
, pp.
203
214
.
34.
Stroud
,
J. S.
,
Berger
,
S. A.
, and
Saloner
,
D.
,
2002
, “
Numerical Analysis of Flow Through a Severely Stenotic Carotid Artery Bifurcation
,”
J. Biomech. Eng.
,
124
, pp.
9
20
.
35.
Samijo
,
S. K.
,
Willigers
,
J. M.
,
Brands
,
P. J.
,
Barkhuysen
,
R.
,
Reneman
,
R. S.
,
Kitslaar
,
P. J. E. H. M.
, and
Hoeks
,
A. P. G.
,
1997
, “
Reproducibility of Shear Rate and Shear Stress Assessment by Means of Ultrasound in the Common Carotid Artery of Young Human Males and Females
,”
Ultrasound Med. Biol.
,
23
(
4
), pp.
583
590
.
You do not currently have access to this content.