WO2004025572A1 - A method of analysing fluid flow in a conduit - Google Patents

A method of analysing fluid flow in a conduit Download PDF

Info

Publication number
WO2004025572A1
WO2004025572A1 PCT/GB2003/004145 GB0304145W WO2004025572A1 WO 2004025572 A1 WO2004025572 A1 WO 2004025572A1 GB 0304145 W GB0304145 W GB 0304145W WO 2004025572 A1 WO2004025572 A1 WO 2004025572A1
Authority
WO
WIPO (PCT)
Prior art keywords
conduit
flow
boundary conditions
geometry
analysis
Prior art date
Application number
PCT/GB2003/004145
Other languages
French (fr)
Inventor
John Graeme Houston
Allan Thomson
Original Assignee
Tayside Flow Technologies Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tayside Flow Technologies Limited filed Critical Tayside Flow Technologies Limited
Priority to AU2003267636A priority Critical patent/AU2003267636A1/en
Publication of WO2004025572A1 publication Critical patent/WO2004025572A1/en

Links

Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T7/00—Image analysis
    • G06T7/0002—Inspection of images, e.g. flaw detection
    • G06T7/0012—Biomedical image inspection
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T17/00—Three dimensional [3D] modelling, e.g. data description of 3D objects
    • G06T17/20—Finite element generation, e.g. wire-frame surface description, tesselation
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/02—Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
    • A61B5/026—Measuring blood flow
    • A61B5/0263—Measuring blood flow using NMR
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T2207/00—Indexing scheme for image analysis or image enhancement
    • G06T2207/30—Subject of image; Context of image processing
    • G06T2207/30004—Biomedical image processing
    • G06T2207/30101—Blood vessel; Artery; Vein; Vascular

Definitions

  • the invention relates to a method of analysing fluid flow in a conduit and especially, but not solely, analysing spiral fluid flow.
  • haemodynamic stress and turbulent flow induces a complex process that promotes atherogenesis by enhancing its three phases of development 1 .
  • the vascular endothelium is damaged/denuded exposing the subendothelial surface to circulating blood 2 .
  • Platelet aggregation and adhesion occur with subsequent microthrombi formation over the micro-fissures induced by the abnormal shear stresses and turbulent flow.
  • the second phase is inflammatory, caused in part by the release of growth factors that induce smooth muscle cell proliferation and stenoses. Lipid accumulation is mediated through abnormal macrophage behavior and changes in local lipid metabolism, e.g.
  • the flow patterns in the arterial system are complex and difficult to analyse. A greater understanding of the blood flow patterns is being achieved with the use of non-invasive imaging. While trans-oesophageal ultrasound has been used to assess blood flow patterns in the ascending and descending arch 5 velocity mapping using MRI is well tolerated and allows a number of methods to be employed. Two dimensional velocity maps can be displayed as vector maps in the vessels or heart 6"11 . Vector mapping has been used in the normal aorta 12 , in aortic coarctation 6 and in aneurysms and grafts 13 . More complex time resolved particle paths have been visualised in the whole volume of the vessel 11 ' 14,15 .
  • a method of analysing fluid flow in a conduit comprising:
  • the method further comprises:
  • the method further comprises verifying the appropriateness of the mesh, typically by comparing the mesh with the constructed geometry.
  • the first set of boundary conditions are selected based on actual fluid flow within the conduit and the second set of boundary conditions are selected based on desired fluid flow within the conduit.
  • the method is for analysing flow in a conduit where the desired fluid flow is spiral flow.
  • the second set of boundary conditions comprises a boundary condition for a desired spiral flow within the conduit.
  • the inlet condition is for the desired spiral flow.
  • results of the first and second analyses are compared by comparing
  • the scanning is performed using a magnetic resonance imaging
  • the fluid is a liquid.
  • the method can be used to analyse flow of fluid in blood vessels in the human or animal body.
  • the method can be used to analyse flow of fluid in blood vessels in the human or animal body.
  • the method can be used to analyse flow of fluid in blood vessels in the human or animal body.
  • the method can be used to analyse flow of fluid in blood vessels in the human or animal body.
  • the method can be used to analyse flow of fluid in blood vessels in the human or animal body.
  • the method can be used to analyse flow of fluid in blood vessels in the human or animal body.
  • the method can be used to analyse flow of fluid in blood vessels in the human or animal body.
  • Figure 1 shows a mesh of a bifurcated arterial segment
  • Figure 2 is an enlarged view of a portion of the mesh
  • Figure 3 is a graph of turbulent kinetic energy versus distance for each of
  • MRI magnetic resonance imaging
  • a computational fluid dynamic cellular matrix (or "mesh") of the segment was then selected.
  • Computational meshes are a conventional analytical tool used in computational fluid dynamics. Typically, such a mesh is a closed cell mesh that comprises a number of cells. First the mesh size is selected to ensure sufficient resolution but not so small that it takes too long to process. The geometry of the cells within the mesh is then selected. Typical cell geometries include “tet” cells which are useful for highly deformed, complex images and "hex" cells which are useful at wall boundaries. The size and type of cells within the mesh can be mixed within the mesh. Normally, the mesh will be constructed using conventional computational fluid dynamics best practice guidelines.
  • Figure 1 shows a constructed mesh 1 for the arterial segment showing a small vessel 2 and a large vessel 3.
  • Figure 2 shows an enlarged view of a portion of the mesh 1.
  • the mesh is then applied to the three dimensional geometry to process data for analysis.
  • the appropriateness of the mesh 1 for the arterial segment is then verified by comparing the mesh 1 with the constructed three dimensional geometry of the arterial segment. If the mesh is determined not to be appropriate, the mesh 1 is modified accordingly or a new mesh is constructed.
  • an analysis model is selected to analyse the processed data.
  • the analysis model is a conventional fluid dynamics model and may be, for example, an inviscid flow model, a laminar flow model, a high Reynolds number turbulent flow model or a low Reynolds number turbulent flow model. The particular model chosen depends on the characteristics of the flow that it is desired to analyse.
  • the physical properties of the blood for the particular flow analysis model selected are then determined and then the boundary conditions are chosen for the analysis model. Two sets of boundary conditions are chosen. The first set of boundary conditions are derived from the actual flow pattern within the arterial segment and the second set of boundary conditions are based on a desired flow pattern within the arterial segment. Normally, the desired flow pattern would be an "ideal" spiral flow pattern.
  • the invention has the advantage of providing an analysis of fluid flow in a conduit. It is particularly useful for analysing fluid flow in blood vessels in the human or animal body as it provides the physician with additional information that the physician can then use to assess the condition of blood vessels for subsequent diagnosis and/or treatment. In particular, the physician can use the invention to compare actual fluid flow pattern in a blood vessel with a desired or ideal flow pattern.
  • Belch JJF Basic science of angioplaty and restenosis: Cellular mechanisms and interventional pharmacotherapy. In: Dyet JF, ed. Textbook of Endovascular Procedures.: W.B. Saunders Company; 2000:3-14.
  • Buonocore MH Visualising blood flow patterns using streamlines, arrows, and particle paths. Magn Reson Med. 1998;40:210-226.

Abstract

A method of analysing fluid flow in a conduit. The internal volume of the conduit is scanned to generate data representing three dimensional geometry of the conduit architecture and fluid flow within the conduit. A three dimensional geometry of the conduit architecture is constructed from the generated data. A computational mesh is selected to apply to the geometry and the computational mesh is then applied to the geometry to process data from the geometry for analysis. A first fluid analysis model is selected and a first set of boundary conditions are selected. A first analysis is then performed to the processed data using the first fluid analysis model and the first set of boundary conditions.

Description

A Method of Analysing Fluid Flow in a Conduit
The invention relates to a method of analysing fluid flow in a conduit and especially, but not solely, analysing spiral fluid flow.
There is a well developed scientific knowledge linking blood flow pattern or haemodynamics with altered arterial wall stress and arterial disease development. Increased haemodynamic stress and turbulent flow induces a complex process that promotes atherogenesis by enhancing its three phases of development1. In the first phase, the vascular endothelium is damaged/denuded exposing the subendothelial surface to circulating blood2. Platelet aggregation and adhesion occur with subsequent microthrombi formation over the micro-fissures induced by the abnormal shear stresses and turbulent flow. The second phase is inflammatory, caused in part by the release of growth factors that induce smooth muscle cell proliferation and stenoses. Lipid accumulation is mediated through abnormal macrophage behavior and changes in local lipid metabolism, e.g. in sterol regulatory element-binding proteins3, which increase the mRNA encoding of the low-density lipoprotein (LDL) receptor and therefore the binding of LDL. Thus both vascular stenoses and lipid-laden plaque formation are promoted. The third phase, that of abnormal adaptive vascular remodeling is also enhanced, as the shear stresses and turbulent flow increase. Whereas exercise promotes improved remodeling vascular risk factors such as LDL cholesterol impair it4. Shear stress also attenuates appropriate remodeling, inducing growth factor release and cytokine production which stimulates extracellular matrix formation by both autocrine and paracrine pathways. All of these processes, occurring as a result of the abnormal vascular shear stresses, increase atherogenesis. In addition, high wall shear stress has been reported in association with atheromatous disease in the great vessels.
The flow patterns in the arterial system are complex and difficult to analyse. A greater understanding of the blood flow patterns is being achieved with the use of non-invasive imaging. While trans-oesophageal ultrasound has been used to assess blood flow patterns in the ascending and descending arch5 velocity mapping using MRI is well tolerated and allows a number of methods to be employed. Two dimensional velocity maps can be displayed as vector maps in the vessels or heart6"11. Vector mapping has been used in the normal aorta12, in aortic coarctation6 and in aneurysms and grafts13. More complex time resolved particle paths have been visualised in the whole volume of the vessel11'14,15.
However, these known methods have the disadvantage that they do not produce a flow and three dimensional geometry of the vessel architecture and relate these to the arterial wall disease process. The combination of vessel geometry, flow data and wall haemodynamics, including stress would be a significant improvement.
In accordance with an aspect of the present invention, there is provided a method of analysing fluid flow in a conduit, the method comprising:
(a) scanning the internal volume of the conduit to generate data representing three dimensional geometry of the conduit architecture and fluid flow within the conduit; (b) constructing a three dimensional geometry of the conduit architecture from the generated data;
(c) selecting a computational mesh to apply to the geometry;
(d) applying the computational mesh to the geometry to process data from the geometry for analysis;
(e) selecting a first fluid analysis model;
(f) selecting a first set of boundary conditions; and
(g) performing a first analysis of the processed data using the first fluid analysis model and the first set of boundary conditions.
Preferably, the method further comprises:
(h) selecting a second set of boundary conditions; (j) performing a second analysis of the processed data using the first fluid analysis model and the second set of boundary conditions; and (k) comparing the results of the first and the second analyses.
Preferably, the method further comprises verifying the appropriateness of the mesh, typically by comparing the mesh with the constructed geometry.
Typically, the first set of boundary conditions are selected based on actual fluid flow within the conduit and the second set of boundary conditions are selected based on desired fluid flow within the conduit.
Preferably, the method is for analysing flow in a conduit where the desired fluid flow is spiral flow. Typically, the second set of boundary conditions comprises a boundary condition for a desired spiral flow within the conduit. Typically, in the
second set of boundary conditions the inlet condition is for the desired spiral flow.
The term "spiral" as used herein covers the mathematical definitions of spiral and
helical, and any combination of spiral and helical.
Typically, the results of the first and second analyses are compared by comparing
the ratio of the first analysis to the second analysis.
Typically, the scanning is performed using a magnetic resonance imaging
technique, but is not limited this technique.
Preferably, the fluid is a liquid. Typically, the method can be used to analyse flow of fluid in blood vessels in the human or animal body. However, the method can
also be used to analyse fluid flow in other types of conduit.
An example of a method of analysing fluid flow in a conduit in accordance with the
invention will now be described with reference to the accompanying drawings, in
which: Figure 1 shows a mesh of a bifurcated arterial segment;
Figure 2 is an enlarged view of a portion of the mesh; and
Figure 3 is a graph of turbulent kinetic energy versus distance for each of
the two vessels in the bifurcated arterial segment showing a comparison of spiral and non-spiral flow. Fluid flow in a bifurcated arterial segment was analysed. First, a magnetic resonance imaging (MRI) scan was performed, the data from the scan was then used to construct a three dimensional geometry of the architecture of the vessel from which the arterial segment to be analysed was selected.
A computational fluid dynamic cellular matrix (or "mesh") of the segment was then selected. Computational meshes are a conventional analytical tool used in computational fluid dynamics. Typically, such a mesh is a closed cell mesh that comprises a number of cells. First the mesh size is selected to ensure sufficient resolution but not so small that it takes too long to process. The geometry of the cells within the mesh is then selected. Typical cell geometries include "tet" cells which are useful for highly deformed, complex images and "hex" cells which are useful at wall boundaries. The size and type of cells within the mesh can be mixed within the mesh. Normally, the mesh will be constructed using conventional computational fluid dynamics best practice guidelines.
Figure 1 shows a constructed mesh 1 for the arterial segment showing a small vessel 2 and a large vessel 3. Figure 2 shows an enlarged view of a portion of the mesh 1.
The mesh is then applied to the three dimensional geometry to process data for analysis. The appropriateness of the mesh 1 for the arterial segment is then verified by comparing the mesh 1 with the constructed three dimensional geometry of the arterial segment. If the mesh is determined not to be appropriate, the mesh 1 is modified accordingly or a new mesh is constructed. Provided that it is verified that the mesh is appropriate, an analysis model is selected to analyse the processed data. The analysis model is a conventional fluid dynamics model and may be, for example, an inviscid flow model, a laminar flow model, a high Reynolds number turbulent flow model or a low Reynolds number turbulent flow model. The particular model chosen depends on the characteristics of the flow that it is desired to analyse.
The physical properties of the blood for the particular flow analysis model selected are then determined and then the boundary conditions are chosen for the analysis model. Two sets of boundary conditions are chosen. The first set of boundary conditions are derived from the actual flow pattern within the arterial segment and the second set of boundary conditions are based on a desired flow pattern within the arterial segment. Normally, the desired flow pattern would be an "ideal" spiral flow pattern.
After the analysis model, the fluid properties and the boundary conditions are determined, analyses are performed for both sets of boundary conditions. The results of both sets of analyses are then compared. Analyses for a non-spiral flow and a spiral flow are shown in Figure 3 for both the large vessel 3 and the small vessel 2 in the bifurcated arterial segment for turbulent kinetic energy versus distance along the arterial segment.
The invention has the advantage of providing an analysis of fluid flow in a conduit. It is particularly useful for analysing fluid flow in blood vessels in the human or animal body as it provides the physician with additional information that the physician can then use to assess the condition of blood vessels for subsequent diagnosis and/or treatment. In particular, the physician can use the invention to compare actual fluid flow pattern in a blood vessel with a desired or ideal flow pattern.
References
1. Belch JJF. Basic science of angioplaty and restenosis: Cellular mechanisms and interventional pharmacotherapy. In: Dyet JF, ed. Textbook of Endovascular Procedures.: W.B. Saunders Company; 2000:3-14.
2. Urbich C, Dernbach E, Reissner A, et al. Shear stress-induced endothelial
cell migration involves integrin signaling via the fibronectin receptor
subunits a5 and a 1. Arterioscler Thromb Vase Biol. 2002;22:69-75.
3. Liu Y, Chen BPC, Lu M, et al. Shear stress activation of SREBPI in
endothelial cells in mediated by integrins. Arterioscler Thromb Vase Biol.
2002;22:76-81.
4. Faxon DP, Coats W, Currier J. Remodelling of the coronary artery after vascular injury. Prog Cardiovasc Dis. 1997;40:129-140.
5. Segadal L, Matre K. Blood velocity distribution in the human ascending
aorta. Circulation. 1987;76:90-100.
6. Mohiaddin RH, Yang GZ, Kilner PJ. Visualisation of flow by vector analysis
of multidirectional cine magnetic resonance velocity mapping: technique
and application. J Comput Assist Tomogr. 1994;18:383-392.
7. Napel S, Lee DH, Frayne R, et al. Visualizing three-dimensional flow with
simulated streamlines and three-dimensional phase-contrast MR imaging. J
Magn Reson Imaging. 1992;2:143-53.
8. Yang GZ, Burger P, Mohiaddin RH. In vivo blood flow analysis and
animation for magnetic resonance imaging. Proc Int Soc Opt Eng (SPUE).
1990;1233:176-182. . Mohiaddin RH, Yang GZ, Burger P, et al. Automatic enhancement animation, and segmentation of flow in peripheral arteries from magnetic resonance phase shift velocity mapping. J Comput Assist Tomogr. 1992;16:176-181. 10. Walker PG, Cranney GB, Scheidegger MG, et al. Computer animation of the time dependent flow in a human left ventricle: an in vivo NMR phase velocity encoding study [Abstract]. Soc Magn Reson Med. 1992;2:2515. 11. Buonocore MH. Algorithms for improving streamlines in 3-D phase contrast angiography. Magn Reson Med. 1994;31 :22-30. 12. Kilner PJ, Yang GZ, Mohiaddin RH, et al. Helical and retrograde secondary flow patterns in the aortic arch studied by three-directional magnetic resonance velocity mapping. Circulation. 1993;88:2235-47.
13. Bogren HG, Mohiaddin RH, Yang GZ, et al. Magnetic resonance velocity vector mapping of blood flow in thoracic aortic aneurysms and grafts. J Thorac Cardiovasc Surg. 1995;110:704-714.
14. Buonocore MH. Visualising blood flow patterns using streamlines, arrows, and particle paths. Magn Reson Med. 1998;40:210-226.
15. Bogren HG, Buonocore MH. 4D magnetic resonance velocity mapping of
blood flow patterns in the aorta in young vs elderly normal subjects. J Magn
Reson Imaging. 1999;10:861-869.

Claims

1. A method of analysing fluid flow in a conduit, the method comprising:
(a) scanning the internal volume of the conduit to generate data representing three dimensional geometry of the conduit architecture and fluid flow within the conduit;
(b) constructing a three dimensional geometry of the conduit architecture from the generated data;
(c) selecting a computational mesh to apply to the geometry; (d) applying the computational mesh to the geometry to process data from the geometry for analysis;
(e) selecting a first fluid analysis model;
(f) selecting a first set of boundary conditions; and
(g) performing a first analysis of the processed data using the first fluid analysis model and the first set of boundary conditions.
2. A method according to any of the preceding claims, wherein the first set of boundary conditions are selected based on actual fluid flow within the conduit.
3. A method according to claim 1 or claim 2, further comprising: (h) selecting a second set of boundary conditions; (j) performing a second analysis of the processed data using the first fluid analysis model and the second set of boundary conditions; and (k) comparing the results of the first and the second analyses.
4. A method according to claim 3, wherein the results of the first and second analyses are compared by comparing the ratio of the first analysis to the second analysis.
5. A method according to claim 3 or claim 4, wherein the second set of boundary conditions are selected based on desired fluid flow within the conduit.
6. A method according to any of the preceding claims, wherein the method is for analysing flow in a conduit where the desired fluid flow is spiral flow.
7. A method according to claim 6 when dependent on any of claims 3 to 5, wherein the second set of boundary conditions comprise a boundary condition for a desired spiral flow within the conduit.
8. A method according to claim 7, wherein in the second set of boundary conditions the inlet condition is for the desired spiral flow.
9. A method according to any of the preceding claims, wherein the appropriateness of the mesh is verified.
10. A method according to claim 9, wherein the appropriateness of the mesh is verified by comparing the mesh with the constructed geometry.
11. A method according to any of the preceding claims, wherein the scanning is performed using a magnetic resonance imaging technique. 12 A method according to any of the preceding claims, wherein the method is used to analyse flow of fluid in blood vessels in the human or animal body.
PCT/GB2003/004145 2002-09-16 2003-09-16 A method of analysing fluid flow in a conduit WO2004025572A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2003267636A AU2003267636A1 (en) 2002-09-16 2003-09-16 A method of analysing fluid flow in a conduit

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB0221434.4 2002-09-16
GB0221434A GB0221434D0 (en) 2002-09-16 2002-09-16 A method of analysing fluid flow in a conduit

Publications (1)

Publication Number Publication Date
WO2004025572A1 true WO2004025572A1 (en) 2004-03-25

Family

ID=9944130

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB2003/004145 WO2004025572A1 (en) 2002-09-16 2003-09-16 A method of analysing fluid flow in a conduit

Country Status (3)

Country Link
AU (1) AU2003267636A1 (en)
GB (1) GB0221434D0 (en)
WO (1) WO2004025572A1 (en)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9589204B2 (en) 2010-09-20 2017-03-07 Koninklijke Philips N.V. Quantification of a characteristic of a lumen of a tubular structure
US9757073B2 (en) 2012-11-06 2017-09-12 Koninklijke Philips N.V. Fractional flow reserve (FFR) index
US9788807B2 (en) 2013-09-06 2017-10-17 Koninklijke Philips N.V. Processing apparatus for processing cardiac data
US9842401B2 (en) 2013-08-21 2017-12-12 Koninklijke Philips N.V. Segmentation apparatus for interactively segmenting blood vessels in angiographic image data
US9867584B2 (en) 2012-12-11 2018-01-16 Koninklijke Philips N.V. Method of determining the blood flow through coronary arteries
US10052032B2 (en) 2013-04-18 2018-08-21 Koninklijke Philips N.V. Stenosis therapy planning
US10258303B2 (en) 2014-06-30 2019-04-16 Koninklijke Philips N.V. Apparatus for determining a fractional flow reserve value
US10368819B2 (en) 2014-07-18 2019-08-06 Koninklijke Philips N.V. Stenosis assessment
US10646185B2 (en) 2015-01-15 2020-05-12 Koninklijke Philips N.V. iFR-CT
US10769780B2 (en) 2015-11-05 2020-09-08 Koninklijke Philips N.V. Collateral flow modelling for non-invasive fractional flow reserve (FFR)
US10898267B2 (en) 2015-10-07 2021-01-26 Koninklijke Philips N.V. Mobile FFR simulation
US10902606B2 (en) 2015-12-22 2021-01-26 Koninklijke Philips N.V. Heart model guided coronary artery segmentation
US11031136B2 (en) 2015-08-05 2021-06-08 Koninklijke Philips N.V. Assistance device and method for an interventional hemodynamic measurement
US11039804B2 (en) 2016-09-16 2021-06-22 Koninklijke Philips N.V. Apparatus and method for determining a fractional flow reserve
US11055848B2 (en) 2012-05-14 2021-07-06 Koninklijke Philips N.V. Determination of a fractional flow reserve (FFR) value for a stenosis of a vessel

Non-Patent Citations (5)

* Cited by examiner, † Cited by third party
Title
LEUPRECHT A, PERKTOLD K, PROSI M, BERK T, TRUBEL W, SCHIMA H: "Numerical study of hemodynamics and wall mechanics in distal end-to-side anastomoses of bypass grafts", JOURNAL OF BIOMECHANICS, vol. 35, 2002, pages 225 - 236, XP002268413 *
MIGLIAVACCA F, KILNER P, PENNATI G, DUBINI G, PIETRABISSA R, FUMERO R, DE LAVAL M: "Computational Fluid Dynamic and Magnetic Resonance Analyses of Flow Distribution Between the Lungs After Total Cavopulmonary Connection", IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, vol. 46, no. 4, April 1999 (1999-04-01), pages 393 - 399, XP002268414 *
MILNER J, MOORE J, RUTT B, STEINMAN D: "Hemodynamics of human carotid artery bifurcations: Computational studies with models reconstructed from magnetic resonance imaging of normal subjects", JOURNAL OF VASCULAR SURGERY, vol. 28, no. 1, July 1998 (1998-07-01), pages 143 - 156, XP008026824 *
SHIPKOWITZ T, RODGERS V, FRAZIN L, CHANDRAN K: "Numerical study on the effect of secondary flow in the human aorta on local shear stress in abdominal aortic branches", JOURNAL OF BIOMECHANICS, vol. 33, 2000, pages 717 - 728, XP002268412 *
STEINMAN D: "Image-Based Computational Fluid Dynamics Medeling in Realistic Arterial Geometries", ANNALS OF BIOMEDICAL ENGINEERING, vol. 30, 2002, pages 483 - 497, XP008026820 *

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9589204B2 (en) 2010-09-20 2017-03-07 Koninklijke Philips N.V. Quantification of a characteristic of a lumen of a tubular structure
US11055848B2 (en) 2012-05-14 2021-07-06 Koninklijke Philips N.V. Determination of a fractional flow reserve (FFR) value for a stenosis of a vessel
US9757073B2 (en) 2012-11-06 2017-09-12 Koninklijke Philips N.V. Fractional flow reserve (FFR) index
US9867584B2 (en) 2012-12-11 2018-01-16 Koninklijke Philips N.V. Method of determining the blood flow through coronary arteries
US10052032B2 (en) 2013-04-18 2018-08-21 Koninklijke Philips N.V. Stenosis therapy planning
US9842401B2 (en) 2013-08-21 2017-12-12 Koninklijke Philips N.V. Segmentation apparatus for interactively segmenting blood vessels in angiographic image data
US9788807B2 (en) 2013-09-06 2017-10-17 Koninklijke Philips N.V. Processing apparatus for processing cardiac data
US10258303B2 (en) 2014-06-30 2019-04-16 Koninklijke Philips N.V. Apparatus for determining a fractional flow reserve value
US10368819B2 (en) 2014-07-18 2019-08-06 Koninklijke Philips N.V. Stenosis assessment
US10646185B2 (en) 2015-01-15 2020-05-12 Koninklijke Philips N.V. iFR-CT
US11031136B2 (en) 2015-08-05 2021-06-08 Koninklijke Philips N.V. Assistance device and method for an interventional hemodynamic measurement
US10898267B2 (en) 2015-10-07 2021-01-26 Koninklijke Philips N.V. Mobile FFR simulation
US10769780B2 (en) 2015-11-05 2020-09-08 Koninklijke Philips N.V. Collateral flow modelling for non-invasive fractional flow reserve (FFR)
US10902606B2 (en) 2015-12-22 2021-01-26 Koninklijke Philips N.V. Heart model guided coronary artery segmentation
US11039804B2 (en) 2016-09-16 2021-06-22 Koninklijke Philips N.V. Apparatus and method for determining a fractional flow reserve

Also Published As

Publication number Publication date
GB0221434D0 (en) 2002-10-23
AU2003267636A1 (en) 2004-04-30

Similar Documents

Publication Publication Date Title
Barker et al. Bicuspid aortic valve is associated with altered wall shear stress in the ascending aorta
Van Ooij et al. Aortic valve stenosis alters expression of regional aortic wall shear stress: New insights from a 4‐dimensional flow magnetic resonance imaging study of 571 subjects
Meierhofer et al. Wall shear stress and flow patterns in the ascending aorta in patients with bicuspid aortic valves differ significantly from tricuspid aortic valves: a prospective study
Ku et al. In vivo validation of numerical prediction of blood flow in arterial bypass grafts
François et al. Four-dimensional, flow-sensitive magnetic resonance imaging of blood flow patterns in thoracic aortic dissections
Wetzel et al. In vivo assessment and visualization of intracranial arterial hemodynamics with flow-sensitized 4D MR imaging at 3T
Lamata et al. Aortic relative pressure components derived from four‐dimensional flow cardiovascular magnetic resonance
Tang et al. Abdominal aortic hemodynamics in young healthy adults at rest and during lower limb exercise: quantification using image-based computer modeling
Van Ooij et al. A methodology to detect abnormal relative wall shear stress on the full surface of the thoracic aorta using four‐dimensional flow MRI
Steinman et al. Computational modeling of arterial biomechanics: insights into pathogenesis and treatment of vascular disease
Taylor et al. Image-based modeling of blood flow and vessel wall dynamics: applications, methods and future directions: Sixth International Bio-Fluid Mechanics Symposium and Workshop, March 28–30, 2008 Pasadena, California
Boussel et al. Phase‐contrast magnetic resonance imaging measurements in intracranial aneurysms in vivo of flow patterns, velocity fields, and wall shear stress: comparison with computational fluid dynamics
Steinman et al. Image-based computational simulation of flow dynamics in a giant intracranial aneurysm
Holloway et al. Imaging of thoracic aortic disease
Osswald et al. Elevated wall shear stress in aortic type B dissection may relate to retrograde aortic type A dissection: a computational fluid dynamics pilot study
WO2004025572A1 (en) A method of analysing fluid flow in a conduit
Harloff et al. Wall shear stress distribution at the carotid bifurcation: influence of eversion carotid endarterectomy
Takehara et al. Abnormal flow dynamics result in low wall shear stress and high oscillatory shear index in abdominal aortic dilatation: initial in vivo assessment with 4D-flow MRI
Houston et al. Two‐dimensional flow quantitative MRI of aortic arch blood flow patterns: Effect of age, sex, and presence of carotid atheromatous disease on prevalence of spiral blood flow
Tsang et al. Blood flow in intracranial aneurysms treated with Pipeline embolization devices: computational simulation and verification with Doppler ultrasonography on phantom models
Nannini et al. Aortic hemodynamics assessment prior and after valve sparing reconstruction: A patient-specific 4D flow-based FSI model
Parekh et al. 4D flow MR imaging of the portal venous system: a feasibility study in children
Kefayati et al. The manifestation of vortical and secondary flow in the cerebral venous outflow tract: an in vivo MR velocimetry study
Shahid et al. Enhanced 4D flow MRI-based CFD with adaptive mesh refinement for flow dynamics assessment in coarctation of the aorta
Zilber et al. Noninvasive morphologic and hemodynamic evaluation of type B aortic dissection: state of the art and future perspectives

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LU MC NL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP

WWW Wipo information: withdrawn in national office

Country of ref document: JP