Computational fluid dynamics (CFD) modeling of nominally patient-specific cerebral aneurysms is increasingly being used as a research tool to further understand the development, prognosis, and treatment of brain aneurysms. We have previously developed virtual angiography to indirectly validate CFD-predicted gross flow dynamics against the routinely acquired digital subtraction angiograms. Toward a more direct validation, here we compare detailed, CFD-predicted velocity fields against those measured using particle imaging velocimetry (PIV). Two anatomically realistic flow-through phantoms, one a giant internal carotid artery (ICA) aneurysm and the other a basilar artery (BA) tip aneurysm, were constructed of a clear silicone elastomer. The phantoms were placed within a computer-controlled flow loop, programed with representative flow rate waveforms. PIV images were collected on several anterior-posterior (AP) and lateral (LAT) planes. CFD simulations were then carried out using a well-validated, in-house solver, based on micro-CT reconstructions of the geometries of the flow-through phantoms and inlet/outlet boundary conditions derived from flow rates measured during the PIV experiments. PIV and CFD results from the central AP plane of the ICA aneurysm showed a large stable vortex throughout the cardiac cycle. Complex vortex dynamics, captured by PIV and CFD, persisted throughout the cardiac cycle on the central LAT plane. Velocity vector fields showed good overall agreement. For the BA, aneurysm agreement was more compelling, with both PIV and CFD similarly resolving the dynamics of counter-rotating vortices on both AP and LAT planes. Despite the imposition of periodic flow boundary conditions for the CFD simulations, cycle-to-cycle fluctuations were evident in the BA aneurysm simulations, which agreed well, in terms of both amplitudes and spatial distributions, with cycle-to-cycle fluctuations measured by PIV in the same geometry. The overall good agreement between PIV and CFD suggests that CFD can reliably predict the details of the intra-aneurysmal flow dynamics observed in anatomically realistic in vitro models. Nevertheless, given the various modeling assumptions, this does not prove that they are mimicking the actual in vivo hemodynamics, and so validations against in vivo data are encouraged whenever possible.

1.
ISUIA Investigators
, 1998, “
Unruptured Intracranial Aneurysms—Risk of Rupture and Risks of Surgical Intervention
,”
N. Engl. J. Med.
0028-4793,
339
, pp.
1725
1733
.
2.
Tummala
,
R. P.
,
Baskaya
,
M. K.
, and
Heros
,
R. C.
, 2005, “
Contemporary Management of Incidental Intracranial Aneurysms
,”
Neurosurg Focus
,
18
, pp.
e9
.
3.
Molyneux
,
A.
,
Kerr
,
R.
,
Stratton
,
I.
,
Sandercock
,
P.
,
Clarke
,
M.
,
Shrimpton
,
J.
, and
Holman
,
R.
, 2002, “
International Subarachnoid Aneurysm Trial (ISAT) of Neurosurgical Clipping Versus Endovascular Coiling in 2143 Patients With Ruptured Intracranial Aneurysms: A Randomised Trial
,”
Lancet
0140-6736,
360
, pp.
1267
1274
.
4.
Molyneux
,
A. J.
,
Kerr
,
R. S.
,
Yu
,
L. M.
,
Clarke
,
M.
,
Sneade
,
M.
,
Yarnold
,
J. A.
, and
Sandercock
,
P.
, 2005, “
International Subarachnoid Aneurysm Trial (ISAT) of Neurosurgical Clipping Versus Endovascular Coiling in 2143 Patients With Ruptured Intracranial Aneurysms: A Randomised Comparison of Effects on Survival, Dependency, Seizures, Rebleeding, Subgroups, and Aneurysm Occlusion
,”
Lancet
0140-6736,
366
, pp.
809
817
.
5.
Asgari
,
S.
,
Wanke
,
I.
,
Schoch
,
B.
, and
Stolke
,
D.
, 2003, “
Recurrent Hemorrhage After Initially Complete Occlusion of Intracranial Aneurysms
,”
Neurosurg. Rev.
0344-5607,
26
, pp.
269
274
.
6.
Kawanabe
,
Y.
,
Sadato
,
A.
,
Taki
,
W.
, and
Hashimoto
,
N.
, 2001, “
Endovascular Occlusion of Intracranial Aneurysms With Guglielmi Detachable Coils: Correlation Between Coil Packing Density and Coil Compaction
,”
Acta Neurochir. Suppl. (Wien)
0065-1419,
143
, pp.
451
455
.
7.
Nagashima
,
H.
,
Kobayashi
,
S.
,
Tanaka
,
Y.
, and
Hongo
,
K.
, 2004, “
Endovascular Therapy Versus Surgical Clipping for Basilar Artery Bifurcation Aneurysm: Retrospective Analysis of 117 Cases
,”
J. Neuropsychiatry Clin. Neurosci.
0895-0172,
11
, pp.
475
479
.
8.
Mantha
,
A.
,
Karmonik
,
C.
,
Benndorf
,
G.
,
Strother
,
C.
, and
Metcalfe
,
R.
, 2006, “
Hemodynamics in a Cerebral Artery Before and After the Formation of an Aneurysm
,”
AJNR Am. J. Neuroradiol.
0195-6108,
27
, pp.
1113
1118
.
9.
Steinman
,
D. A.
,
Milner
,
J. S.
,
Norley
,
C. J.
,
Lownie
,
S. P.
, and
Holdsworth
,
D. W.
, 2003, “
Image-Based Computational Simulation of Flow Dynamics in a Giant Intracranial Aneurysm
,”
AJNR Am. J. Neuroradiol.
0195-6108,
24
, pp.
559
566
.
10.
Shojima
,
M.
,
Oshima
,
M.
,
Takagi
,
K.
,
Torii
,
R.
,
Hayakawa
,
M.
,
Katada
,
K.
,
Morita
,
A.
, and
Kirino
,
T.
, 2004, “
Magnitude and Role of Wall Shear Stress on Cerebral Aneurysm: Computational Fluid Dynamic Study of 20 Middle Cerebral Artery Aneurysms
,”
Stroke
0039-2499,
35
, pp.
2500
2505
.
11.
Hassan
,
T.
,
Timofeev
,
E. V.
,
Saito
,
T.
,
Shimizu
,
H.
,
Ezura
,
M.
,
Matsumoto
,
Y.
,
Takayama
,
K.
,
Tominaga
,
T.
, and
Takahashi
,
A.
, 2005, “
A Proposed Parent Vessel Geometry-Based Categorization of Saccular Intracranial Aneurysms: Computational Flow Dynamics Analysis of the Risk Factors for Lesion Rupture
,”
J. Neurosurg.
0022-3085,
103
, pp.
662
680
.
12.
Jou
,
L. D.
,
Wong
,
G.
,
Dispensa
,
B.
,
Lawton
,
M. T.
,
Higashida
,
R. T.
,
Young
,
W. L.
, and
Saloner
,
D.
, 2005, “
Correlation Between Lumenal Geometry Changes and Hemodynamics in Fusiform Intracranial Aneurysms
,”
AJNR Am. J. Neuroradiol.
0195-6108,
26
, pp.
2357
2363
.
13.
Cebral
,
J. R.
,
Castro
,
M. A.
,
Appanaboyina
,
S.
,
Putman
,
C. M.
,
Millan
,
D.
, and
Frangi
,
A. F.
, 2005, “
Efficient Pipeline for Image-Based Patient-Specific Analysis of Cerebral Aneurysm Hemodynamics: Technique and Sensitivity
,”
IEEE Trans. Med. Imaging
0278-0062,
24
, pp.
457
467
.
14.
Cebral
,
J. R.
,
Castro
,
M. A.
,
Burgess
,
J. E.
,
Pergolizzi
,
R. S.
,
Sheridan
,
M. J.
, and
Putman
,
C. M.
, 2005, “
Characterization of Cerebral Aneurysms for Assessing Risk of Rupture by Using Patient-Specific Computational Hemodynamics Models
,”
AJNR Am. J. Neuroradiol.
0195-6108,
26
, pp.
2550
2559
.
15.
Byun
,
H. S.
, and
Rhee
,
K.
, 2004, “
CFD Modeling of Blood Flow Following Coil Embolization of Aneurysms
,”
Med. Eng. Phys.
1350-4533,
26
, pp.
755
761
.
16.
Groden
,
C.
,
Laudan
,
J.
,
Gatchell
,
S.
, and
Zeumer
,
H.
, 2001, “
Three-Dimensional Pulsatile Flow Simulation Before and After Endovascular Coil Embolization of a Terminal Cerebral Aneurysm
,”
J. Cereb. Blood Flow Metab.
0271-678X,
21
, pp.
1464
1471
.
17.
Stuhne
,
G. R.
, and
Steinman
,
D. A.
, 2004, “
Finite-Element Modeling of the Hemodynamics of Stented Aneurysms
,”
ASME J. Biomech. Eng.
0148-0731,
126
, pp.
382
387
.
18.
Aenis
,
M.
,
Stancampiano
,
A. P.
,
Wakhloo
,
A. K.
, and
Lieber
,
B. B.
, 1997, “
Modeling of Flow in a Straight Stented and Nonstented Side Wall Aneurysm Model
,”
ASME J. Biomech. Eng.
0148-0731,
119
, pp.
206
212
.
19.
Cebral
,
J. R.
, and
Lohner
,
R.
, 2005, “
Efficient Simulation of Blood Flow Past Complex Endovascular Devices Using an Adaptive Embedding Technique
,”
IEEE Trans. Med. Imaging
0278-0062,
24
, pp.
468
476
.
20.
Ford
,
M. D.
,
Stuhne
,
G. R.
,
Nikolov
,
H. N.
,
Habets
,
D. F.
,
Lownie
,
S. P.
,
Holdsworth
,
D. W.
, and
Steinman
,
D. A.
, 2005, “
Virtual Angiography for Visualization and Validation of Computational Models of Aneurysm Hemodynamics
,”
IEEE Trans. Med. Imaging
0278-0062,
24
, pp.
1586
1592
.
21.
Ford
,
M. D.
,
Nikolov
,
H. N.
,
Milner
,
J. S.
,
Kalata
,
W.
,
Loth
,
F.
,
Lownie
,
S. P.
,
Holdsworth
,
D. W.
, and
Steinman
,
D. A.
, 2005, “
In Vitro Validation of an Image-Based CFD Model of an Anatomically Realistic Cerebral Aneurysm
,” presented at
ASME Summer Bioengineering Conference
,
Vail, Colorado
.
22.
Ferguson
,
G. G.
, 1970, “
Turbulence in Human Intracranial Saccular Aneurysms
,”
J. Neurosurg.
0022-3085,
33
, pp.
485
497
.
23.
Fahrig
,
R.
,
Fox
,
A. J.
,
Lownie
,
S.
, and
Holdsworth
,
D. W.
, 1997, “
Use of a C-Arm System to Generate True Three-Dimensional Computed Rotational Angiograms: Preliminary In Vitro and In Vivo Results
,”
AJNR Am. J. Neuroradiol.
0195-6108,
18
, pp.
1507
1514
.
24.
Yedavalli
,
R. V.
,
Loth
,
F.
,
Yardimci
,
A.
,
Pritchard
,
W. F.
,
Oshinski
,
J. N.
,
Sadler
,
L.
,
Charbel
,
F.
, and
Alperin
,
N.
, 2001, “
Construction of a Physical Model of the Human Carotid Artery Based on In Vivo Magnetic Resonance Images
,”
ASME J. Biomech. Eng.
0148-0731,
123
, pp.
372
376
.
25.
Wetzel
,
S. G.
,
Ohta
,
M.
,
Handa
,
A.
,
Auer
,
J. M.
,
Lylyk
,
P.
,
Lovblad
,
K. O.
,
Babic
,
D.
, and
Rufenacht
,
D. A.
, 2005, “
From Patient to Model: Stereolithographic Modeling of the Cerebral Vasculature Based on Rotational Angiography
,”
AJNR Am. J. Neuroradiol.
0195-6108,
26
, pp.
1425
1427
.
26.
Knox
,
K.
,
Kerber
,
C. W.
,
Singel
,
S. A.
,
Bailey
,
M. J.
, and
Imbesi
,
S. G.
, 2005, “
Stereolithographic Vascular Replicas From CT Scans: Choosing Treatment Strategies, Teaching, and Research From Live Patient Scan Data
,”
AJNR Am. J. Neuroradiol.
0195-6108,
26
, pp.
1428
1431
.
27.
Ford
,
M. D.
,
Alperin
,
N.
,
Lee
,
S. H.
,
Holdsworth
,
D. W.
, and
Steinman
,
D. A.
, 2005, “
Characterization of Volumetric Flow Rate Waveforms in the Normal Internal Carotid and Vertebral Arteries
,”
Physiol. Meas
0967-3334,
26
, pp.
477
488
.
28.
Frayne
,
R.
,
Holdsworth
,
D. W.
,
Gowman
,
L. M.
,
Rickey
,
D. W.
,
Drangova
,
M.
,
Fenster
,
A.
, and
Rutt
,
B. K.
, 1992, “
Computer-Controlled Flow Simulator for MR Flow Studies
,”
J. Magn. Reson Imaging
1053-1807,
2
, pp.
605
612
.
29.
1981,
CRC Handbook of Chemistry and Physiscs
,
61st ed.
,
CRC
,
Boca Raton, FL
.
30.
Hopkins
,
L. N.
,
Kelly
,
J. T.
,
Wexler
,
A. S.
, and
Prasad
,
A. K.
, 2000, “
Particle Image Velocimetry Measurements in Complex Geometries
,”
Exp. Fluids
0723-4864,
29
, pp.
91
95
.
31.
Fahrig
,
R.
,
Nikolov
,
H.
,
Fox
,
A. J.
, and
Holdsworth
,
D. W.
, 1999, “
A Three-Dimensional Cerebrovascular Flow Phantom
,”
Med. Phys.
0094-2405,
26
, pp.
1589
1599
.
32.
Antiga
,
L.
,
Ene-Iordache
,
B.
,
Caverni
,
L.
,
Cornalba
,
G. P.
, and
Remuzzi
,
A.
, 2002, “
Geometric Reconstruction for Computational Mesh Generation of Arterial Bifurcations From CT Angiography
,”
Comput. Med. Imaging Graph.
0895-6111,
26
, pp.
227
235
.
33.
Ethier
,
C. R.
,
Prakash
,
S.
,
Steinman
,
D. A.
,
Leask
,
R. I.
,
Couch
,
G. G.
, and
Ojha
,
M.
, 2000, “
Steady Flow Separation Patterns in a 45Degree Junction
,”
J. Fluid Mech.
0022-1120,
411
, pp.
1
38
.
34.
Minev
,
P. D.
, and
Ethier
,
C. R.
, 1999, “
A Characteristic/Finite Element Algorithm for the 3-D Navier–Stokes Equations Using Unstructured Grids
,”
Comput. Methods Appl. Mech. Eng.
0045-7825,
178
, pp.
39
50
.
35.
Ethier
,
C. R.
,
Steinman
,
D. A.
, and
Ojha
,
M.
, 1999,
Comparisons Between Computational Hemodynamics, Photochromic Dye Flow Visualization and Magnetic Resonance Velocimetry
,
WIT
,
Southhampton
.
36.
Steinman
,
D. A.
,
Thomas
,
J. B.
,
Ladak
,
H. M.
,
Milner
,
J. S.
,
Rutt
,
B. K.
, and
Spence
,
J. D.
, 2002, “
Reconstruction of Carotid Bifurcation Hemodynamics and Wall Thickness Using Computational Fluid Dynamics and MRI
,”
Magn. Reson. Med.
0740-3194,
47
, pp.
149
159
.
37.
Acevedo-Bolton
,
G.
,
Jou
,
L. D.
,
Dispensa
,
B. P.
,
Lawton
,
M. T.
,
Higashida
,
R. T.
,
Martin
,
A. J.
,
Young
,
W. L.
, and
Saloner
,
D.
, 2006, “
Estimating the Hemodynamic Impact of Interventional Treatments of Aneurysms: Numerical Simulation With Experimental Validation: Technical Case Report
,”
Neurosurgery
0148-396X,
59
, pp.
E429
E430
.
38.
Imbesi
,
S. G.
, and
Kerber
,
C. W.
, 1999, “
Analysis of Slipstream Flow in Two Ruptured Intracranial Cerebral Aneurysms
,”
AJNR Am. J. Neuroradiol.
0195-6108,
20
, pp.
1703
1705
.
39.
Imbesi
,
S. G.
, and
Kerber
,
C. W.
, 2001, “
Analysis of Slipstream Flow in a Wide-Necked Basilar Artery Aneurysm: Evaluation of Potential Treatment Regimens
,”
AJNR Am. J. Neuroradiol.
0195-6108,
22
, pp.
721
724
.
40.
Tateshima
,
S.
,
Grinstead
,
J.
,
Sinha
,
S.
,
Nien
,
Y. L.
,
Murayama
,
Y.
,
Villablanca
,
J. P.
,
Tanishita
,
K.
, and
Vinuela
,
F.
, 2004, “
Intraaneurysmal Flow Visualization by Using Phase-Contrast Magnetic Resonance Imaging: Feasibility Study Based on a Geometrically Realistic In Vitro Aneurysm Model
,”
J. Neurosurg.
0022-3085,
100
, pp.
1041
1048
.
41.
Tateshima
,
S.
,
Murayama
,
Y.
,
Villablanca
,
J. P.
,
Morino
,
T.
,
Takahashi
,
H.
,
Yamauchi
,
T.
,
Tanishita
,
K.
, and
Vinuela
,
F.
, 2001, “
Intraaneurysmal Flow Dynamics Study Featuring an Acrylic Aneurysm Model Manufactured Using a Computerized Tomography Angiogram as a Mold
,”
J. Neurosurg.
0022-3085,
95
, pp.
1020
1027
.
42.
Lieber
,
B. B.
,
Livescu
,
V.
,
Hopkins
,
L. N.
, and
Wakhloo
,
A. K.
, 2002, “
Particle Image Velocimetry Assessment of Stent Design Influence on Intra-Aneurysmal Flow
,”
Ann. Biomed. Eng.
0090-6964,
30
, pp.
768
777
.
43.
Liou
,
T. M.
,
Liou
,
S. N.
, and
Chu
,
K. L.
, 2004, “
Intra-Aneurysmal Flow With Helix and Mesh Stent Placement Across Side-Wall Aneurysm Pore of a Straight Parent Vessel
,”
ASME J. Biomech. Eng.
0148-0731,
126
, pp.
36
43
.
44.
Hassan
,
T.
,
Timofeev
,
E. V.
,
Ezura
,
M.
,
Saito
,
T.
,
Takahashi
,
A.
,
Takayama
,
K.
, and
Yoshimoto
,
T.
, 2003, “
Hemodynamic Analysis of an Adult Vein of Galen Aneurysm Malformation by Use of 3D Image-Based Computational Fluid Dynamics
,”
AJNR Am. J. Neuroradiol.
0195-6108,
24
, pp.
1075
1082
.
45.
Valencia
,
A.
, and
Zarate
,
A.
Galvez
,
M.
, and
Badilla
,
L.
, 2006, “
Non-Newtonian Blood Flow Dynamics in a Right Internal Carotid Artery with a Saccular Aneurysm
,”
Int. J. Numer. Methods Fluids
0271-2091,
50
, pp.
751
764
.
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