Pulsatile and steady flow fields in cerebrovascular aneurysm models of various sizes are presented in terms of laser-Doppler velocimetry measurements and flow visualization. The bifurcation angle was 140 deg and volume flow rate ratio between the branches was 3:1. The mean, peak, and minimal Reynolds numbers based on the bulk average velocity and diameter of the parent vessel were 600, 800, and 280, respectively. It is found that among the tested sizes there exists a middle range of aneurysm sizes, above and below which the forced-vortex inside the aneurysmal model is weaker and lacking, respectively, whereas in the middle range of the tested sizes the forced vortex is stronger and the fluctuation level is higher near the dome. The present results also identify the major fluid dynamic factors of the aneurysmal promotion or rupture for the medium and larger aneurysms, respectively. Furthermore, the maximum fluctuation intensity is found to increase with aneurysm size. The locations of the maximum fluctuation intensity are found to occur in the bifurcation area or at the neck instead of intra-aneurysm.

1.
Bicen
A. F.
,
1982
, “
Refraction Correction for LDA Measurements in Flows With Curved Optical Boundary
,”
TSI Quarterly
, Vol.
VIII
, No.
2
, Apr–June, pp.
10
12
.
2.
Black
S. P. W.
, and
German
W. L.
,
1960
, “
Observation on the Relationship Between the Volume and the Size of the Orifice of Experimental Aneurysms
,”
J. Neurosurg
, Vol.
17
, pp.
984
990
.
3.
Boadway, J. D., and Karaham, E., 1981, “Correction of Laser Doppler Anemometer Reading for Refraction at Cylindrical Interfaces,” DISA Information, No. 26, Feb., pp. 4–6.
4.
Bosmans
H.
,
Wilms
O.
,
Marchal
G.
,
Demaerel
P.
, and
Baert
A. L.
,
1995
, “
Characterization of Intracranial Aneurysms With MR-Angiography
,”
Neuroradiology
, Vol.
37
, pp.
262
266
.
5.
Chang
J.
, and
Roach
M. R.
,
1987
, “
Hemodynamic Method to Predict Whether Hunterian Ligation of the Basilar Artery Will Lead to Thromobosis of Basilar Bifurcation Aneurysms
,”
Neurosurgery
, Vol.
20
, No.
2
, pp.
249
253
.
6.
Crawford
T.
,
1959
, “
Some Observations of the Pathogenesis and Natural History of Intracranial Aneurysms
,”
J. Neuro. Neurosurg. Psychiatry
, Vol.
22
, pp.
259
266
.
7.
Crompton
M. R.
,
1966
a, “
The Pathogenesis of Cerebral Aneurysms
,”
Brain
, Vol.
89
, pp.
797
814
.
8.
Crompton
M. R.
,
1966
b, “
Mechanism of Growth and Rupture in Cerebral Berry Aneurysms
,”
Br. Med. J.
, Vol.
1
, pp.
1138
1142
.
9.
Ferguson
G. G.
,
1970
, “
Turbulence in Human Intracranial Saccular Aneurysms
,”
J. Neurosurg.
, Vol.
33
, pp.
485
497
.
10.
Ferguson
G. G.
,
1972
, “
Physical Factors in the Initiation, Growth, and Rupture of Human Intracranial Saccular Aneurysm
,”
J. Neurosurg.
, Vol.
37
, pp.
666
677
.
11.
Friedman
M. H.
,
Hutchins
G. M.
,
Bargeron
C. B.
,
Deters
O. J.
, and
Mark
F. F.
,
1981
, “
Correlation Between Intimal Thickness and Fluid Shear in Human Arteries
,”
Atherosclerosis
, Vol.
39
, pp.
425
436
.
12.
Forbus
W. D.
,
1930
, “
On the Origin of Miliary Aneurysms of the Superficial Cerebral Arteries
,”
Bull. Johns Hopkins Hosp.
, Vol.
478
, pp.
239
284
.
13.
Fry
D. L.
,
1968
a, “
Acute Vascular Endothelial Changes Associated With Increased Blood Velocity Gradients
,”
Cir. Res.
, Vol.
22
, pp.
165
197
.
14.
Fry
D. L.
,
1968
b, “
Certain Histological and Chemical Responses of the Vascular Interface to Acutely Induced Mechanical Stress in the Aorta of the Dog
,”
Circ. Res.
, Vol.
22
, pp.
165
197
.
15.
Fry
D. L.
,
1969
, “
Certain Histological and Chemical Responses of the Vascular Interface to Acutely Induced Mechanical Stress in the Aorta of the Dog
,”
Circ. Res.
, Vol.
14
, pp.
93
108
.
16.
Hayashi
S.
,
Arimoto
T.
,
Itakura
T.
,
Fujii
T.
,
Nishiguci
T.
, and
Komai
N.
,
1981
, “
The Association of Intracranial Aneurysms and Arteriovenous Malformation of the Brain
,”
J. Neurosurg.
, Vol.
55
, pp.
971
975
.
17.
Kaufman
J. A.
,
Geller
S. C.
,
Petersen
M. J.
,
Cambria
R. P.
,
Prince
M. R.
, and
Waltman
A. C.
,
1994
, “
MR-Imaging (Including MR-Angiography) of Abdominal Aortic-Aneurysms-Comparison With Conventional Angiography
,”
American J. Roentgenology
, Vol.
163
, pp.
203
210
.
18.
Kerber
C. W.
, and
Heilman
C. B.
,
1983
, “
Flow in Experimental Berry Aneurysms: Method and Model
,”
AJNR
, Vol.
4
, pp.
374
377
.
19.
Koulouris
S.
, and
Rizzoli
H.
,
1981
, “
Coexisting Intracranial Aneurysm and Arteriovenous Malformation
,”
Neurosurgery
, Vol.
8
, pp.
219
222
.
20.
Liepsch
D.
,
Poll
A.
, and
Steiger
H. J.
,
1991
, “
Fluid Dynamic Studies in Terminal Aneurysms
,”
Medical & Biological Engineering & Computing
, Vol.
29
, Supplement, p.
19
19
.
21.
Liou
T. M.
, and
Chang
T. W.
,
1993
a, “
Flow Fields in a Simulated Axisymmetric Terminal Aneurysm With Symmetric and Asymmetric Outflows
,”
Experimental Thermal and Fluid Science
, Vol.
7
, pp.
362
369
.
22.
Liou
T. M.
,
Chang
T. W.
, and
Chang
W. C.
,
1993
b, “
Effects of the Bifurcation Angle on the Steady Flow Structure in Model Saccular Aneurysms
,”
Experiments in Fluids
, Vol.
14
, pp.
289
295
.
23.
Liou
T. M.
,
Chang
T. W.
, and
Chang
W. C.
,
1994
, “
Pulsatile Flow Through a Bifurcation With a Cerebrovascular Aneurysm
,”
ASME JOURNAL OF BIOMECHANICAL ENGINEERING
, Vol.
116
, pp.
112
118
.
24.
Liou, T. M., Chang, W. C., and Liao, C. C., 1996a, “Laser-Doppler Velocimetry Measurements in Lateral Model Aneurysms of Various Sizes,” Experiment in Fluid (in press).
25.
Liou
T. M.
,
Chang
W. C.
, and
Liao
C. C.
,
1996
b, “
Laser-Doppler Velocimetry Measurements of Fluid Flow in Model Aneurysms of Various Sizes With Equal Outflow Rates
,”
The Ninth International Symposium on Transport Phenomena in Thermal-Fluids Engineering
, June 25–28, National University of Singapore, Singapore, Vol.
1
, pp.
109
114
.
26.
Liou
T. M.
, and
Liao
C. C.
,
1997
, “
Study of Pulsatile Flows in Lateral Aneurysm Models on a Straight Parent Vessel Using Particle Tracking Velocimetry
,”
1st Pacific Symposium on Flow Visualization and Image Processing
, Vol.
3
, pp.
207
223
.
27.
Lo¨w
M.
,
Perktold
K.
, and
Rauning
R.
,
1993
, “
Hemodynamics in Rigid and Distensible Saccular Aneurysms: a Numerical Study of Pulsatile Flow Characteristics
,”
Biorheology
, Vol.
30
, pp.
287
298
.
28.
McCormick
W. F.
,
1969
, “
Vascular Disorders of Nervous Tissue: Anomalies, Malformations, and Aneurysms
,”
Structure and Function of the Nervous Tissue
, G. Bourne, ed., New York, Academic Press, Vol.
3
, pp.
563
581
.
29.
McCormick
W. F.
, and
Acosta-Rua
G. J.
,
1970
, “
The Size of Intracranial Saccular Aneurysms: An Autopsy Study
,”
J. Neurosurg.
, Vol.
33
, pp.
422
427
.
30.
Meyer
F. B.
,
Huston
J.
, and
Riederer
S. S.
,
1993
, “
Pulsatile Increases in Aneurysm Size Determined by Cine Phase-Contrast MR Angiography
,”
J. Neurosurg.
, Vol.
78
, pp.
878
883
.
31.
Niimi
H.
,
Kawano
Y.
, and
Sugiyama
I.
,
1984
, “
Structure of Blood Flow Through a Curved Vessel With an Aneurysm
,”
Biorheology
, Vol.
21
, pp.
603
615
.
32.
Perkold
K.
,
Peter
R.
, and
Resch
M.
,
1989
, “
Pulsatile Non-Newtonian Blook Flow Simulation Through a Bifurcation With an Aneurysm
,”
Biorheology
, Vol.
26
, pp.
1011
1030
.
33.
Pool, J. L., and Potts, D. G., 1965, Aneurysms and Arteriovenous Anomalies of the Brain: Diagnosis and Treatment, Harper & Row, New York.
34.
Roach
M.
,
Scott
S.
, and
Ferguson
G. G.
,
1972
, “
The Hemodynamic Importance of Geometry of Bifurcations in the Circle of Willis (Glass Model Studies)
,”
Stroke
, Vol.
3
, pp.
255
267
.
35.
Roach
M. R.
,
1978
, “
A Model Study of Why Some Intracranial Aneurysms Thromobose but Others Rupture
,”
Stroke
, Vol.
9
, pp.
583
587
.
36.
Sahs
A. L.
,
1966
, “
Observations on the Pathology of Saccular Aneurysms
,”
J. Neurosurg.
, Vol.
24
, pp.
792
805
.
37.
Simkins
T. E.
, and
Stehbens
W. E.
,
1974
, “
Vibrations Recorded From the Adventitial Surface of Aneurysms and Arteriovenous Fistulas
,”
Vasc. Surg.
, Vol.
8
, pp.
153
165
.
38.
Stehbens
W. E.
,
1959
, “
Medial Defects of the Cerebral Arteries of Man
,”
J. Pathol. Bacteriol.
, Vol.
78
, pp.
179
185
.
39.
Stehbens
W. E.
,
1963
, “
Aneurysms and Anatomical Variation of Cerebral Arteries
,”
Archs. Path.
, Vol.
75
, pp.
45
64
.
40.
Stehbens
W. E.
,
1989
, “
Etiology of Intracranial Berry Aneurysms
,”
J. Neurosurg.
, Vol.
70
, pp.
823
831
.
41.
Steiger
H. J.
, and
Reulen
H. J.
,
1986
, “
Low Frequency Flow Fluctuations in Saccular Aneurysms
,”
Acta Neurochir. (Wien)
, Vol.
83
, pp.
131
137
.
42.
Steiger
H. J.
,
Poll
A.
,
Liepsch
D.
, and
Reulen
H. J.
,
1987
, “
Basic Flow Structure in Saccular Aneurysms: a Flow Visualization Study
,”
Heart and Vessels
, Vol.
3
, pp.
55
65
.
43.
Steiger
H. J.
,
Poll
A.
,
Liepsch
D.
, and
Reulen
H. J.
,
1988
, “
Hemodynamic Stress in Terminal Aneurysms
,”
Acta Neurochir.
, Vol.
93
, pp.
18
23
.
44.
Steiger
H. J.
,
1991
, “
Growth of Cerebral Saccular Aneurysm
,”
Medical & Biological Engineering & Computing
, Vol.
29
, Supplement, p.
19
19
.
45.
Suuki
J.
, and
Ohara
H.
,
1978
, “
Clinicopathological Study of Cerebral Aneurysms: Origin, Rupture, and Growth
,”
J. Neurosurg.
, Vol.
48
, pp.
505
514
.
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