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THE “ANEURISK” PROJECTIL PUNTO

www2.mate.polimi.it:8080/aneurisk

S.Bacigaluppi, E. Boccardi, L. Antiga, B. Ene-Iordache, M. Piccinelli, A. Remuzzi,

G. Dubini, F. Migliavacca, L. Socci, P. Secchi, S. Vantini, T. Passerini, M.R. De Luca

Alessandro Veneziani

MOX-Dept. of Mathematics-Politecnico di Milano

Dept. of Math & CS-Emory University-Atlanta

10 Marzo 2008

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Outline

• A. Veneziani (20 min)

• IRFMN (20 min)

• MOX-Stat (20 min)

• LaBS (20 min)

• MOX-NumAnal (20 min)

• Discussion

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ANEURISK GOAL: To highlight the possible relationshipslinking vascular morphology and

development/rupture risks in Cerebral Aneurysms

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ANEURISK: Yet another CFD

project on Cerebral

Aneurysms???• Many efforts have been devoted to Cerebral Aneurysms CFD

investigations in the last years:

– ANEURIST

– Cebral, Castro, et al

– Hassan et al.

– Steinman et al.,

– …

• Some common features:

– Real geometries: from medical images to computational grids

– Descriptive morphological analysis + CFD analysis

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So, what’s new or different in Aneurisk?

2. Advanced statistical tools for Morphological Analysis

Demanding for custom specific codes for Geometrical Reconstruction

1. Non local perspective: influence of upstream geometry

a) Analysis of extended morphological features

b) Multiscale CFD

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DATADATADATADATA----BASEBASEBASEBASE

GEOMETRICAL GEOMETRICAL GEOMETRICAL GEOMETRICAL ANALYSISANALYSISANALYSISANALYSIS

NUMERICAL NUMERICAL NUMERICAL NUMERICAL MODELINGMODELINGMODELINGMODELING

STATISTICALSTATISTICALSTATISTICALSTATISTICALANALYSISANALYSISANALYSISANALYSIS

STRUCTURE OF THE PROJECT

Clinical Data

(DICOM)

3D reconstruction and

semi-automatic

detection of relevant

morphological features

Correlation,

Functional Data Analysis

3D Simulations, FSI,

WSS Computation,…

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Preprocessing

IRFMN

(VMTK)

Statistical Analysis

MOX

FPCA

Modeling & Simulations

MOX

CFD

MOX

Structure

LaBS

Structure

& Remodel

Niguarda

PostProcessing

Aneurisk

Medical Devices

L.AntigaM. Piccinelli

P. SecchiS. VantiniL. Sangalli

A. VenezianiT. Passerini

A. VenezianiM. R. De Luca

G. DubiniG. Pennati, L. Socci

A. VenezianiS. BacigaluppiE. Boccardi

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Unstructured AneuriskPersonnel

M. Piccinelli

T. Passerini

L. Socci

S. Vantini

� M. R. De Luca

� L. Sangalli

� S. Bacigaluppi

Supported by the Project:

Supported by different Grants:

TOTAL BUDGET: 235000€

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Research Outcomes (2007/2008)Papers 1) M. Piccinelli, S. Bacigaluppi, E. Boccardi, B. Ene-Iordache, A. Remuzzi, A. Veneziani, L.

Antiga, Influence of internal carotid artery geometry on aneurysm location and orientation: a computational geometry study. Tech Rep. 22-2007 Math & CS Dept Emory University, submitted2) P.Vena, G. Gastaldi, L. Socci, G. Pennati, An anisotropic model for tissue growth and remodeling during early development of cerebral aneurysms. ComputationalMaterials Science (2008) to appear.

3) L.M.Sangalli, P.Secchi, S.Vantini, A.Veneziani, (2007), Smoothing and dimensionreduction of 3D centerlines of inner carotid arteries by free-knots regression splines. Tech. Rep., MOX 23/07, Dip. di Matematica, Politecnico di Milano, submitted

4) L.M.Sangalli, P.Secchi, S.Vantini, A.Veneziani, (2007), Explorative Functional Data Analysis. A Case Study: Geometrical Features of the Internal Carotid Artery. Tech. Rep.MOX 24/07, Dip. di Matematica, Politecnico di Milano, accepted on ASA

In preparation:

L. Formaggia, T. Passerini, M.R. De Luca, A. Quarteroni, A. Veneziani (end of March 2008)

T. Passerini, P. Secchi, S. Vantini, S. Vele, A. Veneziani

S. Bacigaluppi, E. Boccardi, A. Veneziani

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PhD Theses (est 2008)

T. Passerini

L. Socci

S. Vantini

M.R. De Luca

II Lev Theses (2007/08)

S. Vele

M. Dalla Rosa

V. Vitelli

G. Pierantoni

L. Botti

I Lev Theses (2007)

R. Caldana

D. Fumagalli

E. Mazzoleni

G. Trombin

Conference Proceedings

P. VENA, D.GASTALDI, L.SOCCI, G. PENNATI, CONTRO R.: A constituent-based computational model for vascular remodelling of a growing cerebral aneurysm. Computational Plasticity 2007 . (vol. 1, pp. 220-223). Proceeding of IX Computational Plasticity, Barcelona, September 5th – 7th.

SANGALLI, L.M., SECCHI, P., VANTINI, S. (2008):A case study in functional data analysis; investigating the geometry of the internal

carotid artery for cerebral aneurysms classification XLIV Riunione Scientifica Società Italiana di Statistica, Università della Calabria.

SANGALLI, L. M., VANTINI, S. (2008):“Registration of Functional Data: Aligning Inner Carotid Artery Centerlines”

XLIV Riunione Scientifica Società Italiana di Statistica, Università della Calabria.

SANGALLI, L. M., VANTINI, S. (2008):“Free knot regression splines for 3-dimensional functional data, with applications to the analysis

of Inner Carotid Artery centerlines” XLIV Riunione Scientifica Società Italiana di Statistica, Università della Calabria.

SANGALLI, L.M., SECCHI, P., VANTINI, S. (2008):Explorative functional data analysis for 3D-geometries of the Inner Carotid Artery

First international Workshop on Functional and Operatorial Statistics IWFOS'2008, University Paul Sabatier, Toulouse, France.

SANGALLI, L.M., SECCHI, P., VANTINI, S. (2007):“Functional Data Analysis for 3D-Geometries of the Inner Carotid Artery” , Book of

Short Papers S.Co. 2007 Complex Models and Computational Intensive Methods for Estimation and Prediction, pp. 427-432 a cura di P.

Mantovan, A. Pastore, S. Tonellato CLEUP Editore.

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Talks & Conferences in 2007/2008

Collaborations started on similar topics1 Pittsburgh University, Dept. of Mech. Engr. (A.M. Robertson)

2 Emory University, Dept. of Math & CS (A. Veneziani)

⇒ Grant URC (30000$) in 2008

3 Imperial College, London (J. Peirò, J. Alaustrey)

⇒ Grant British-Council/CRUI (3000£) in 2008

1. Emory University, Feb 2007 (invited)

2. Pittsburgh University, Feb 2007 (invited)

3. Matematica Uomo-Ambiente, Montecatini, Mar 2007

4. SIMAI Parma, May 2007

5. ICIAM Zurich, Jul 2007

6. Comp Plasticity, Barcelona, Sep 2007 (invited)

7. Fifth Conference on Complex Models and Computational Intensive Methods, Venezia, Sep 2007

8. CRiSM Centre for Research in Statistical Methodology, Department of Statistics, Warwick University, UK, Sep 2007

9. Univerisità del Piemonte Orientale, Oct 2007 (invited)

10. Emory Hospital, Nov 2007 (invited)

11. NeuroMath, Rome, Dec 2007

12. Symp Comp Meth Biomech&Biomed Eng, Feb 2008

13. Fifth International Bio-Fluid Symposium and Workshop, Caltech, Pasadena,CA, March 2008.

14. SIAM Conference GA State Univ, Mar 2008

15. XLIV Riunione Scientifica Società Italiana di Statistica, Università della Calabria, Jun 2008 (3 talks, 1 invited)

16. IWFOS'2008, University Paul Sabatier, Toulouse, France, Jun 2008

17. 16 European Society of Biomech, Jul 2008 (3 talks)

18. SIAM Conference California, Jul 2008

19. BERGAMOSCIENZA, Sep 2008 (invited)

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TASKS ACCOMPLISHED

� Set up of the pipeline from DICOM Data to Numerical Simulations

1 VMTK with automatic centerlines computation

2 Life V

� Empirical analysis of morphological results: correlation with rupture

� Statistical analysis of morphological results: correlation of parent vessel

features with aneurysms position

� CFD Analysis: agreement with statistical results, cross-validation with Wall

Shear Stress analysis

� Fruitful cross validation with Dr. Boccardi

TASKS PARTIALLY ACCOMPLISHED (ongoing)

TASKS FAILED (SO FAR)

� Structure Simulation (Wulandana-Robertson model)

� Parallel Set-Up of the CFD Solver

� Integration with Neurosurgeons

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Why Aneurisk 2?� Extension of the statistical analysisExtension of the statistical analysisExtension of the statistical analysisExtension of the statistical analysis

�Direct correlation with Rupture

�More data (follow up?)

�More morphological features

� Extension of CFD analysisExtension of CFD analysisExtension of CFD analysisExtension of CFD analysis

�More data

�More indexes (Impingement regions)

� FluidFluidFluidFluid----Structure Interaction SimulationsStructure Interaction SimulationsStructure Interaction SimulationsStructure Interaction Simulations

�Image-based simulations (after URC Grant)

�Methodological/Technological Transfer in Clinical PracticeMethodological/Technological Transfer in Clinical PracticeMethodological/Technological Transfer in Clinical PracticeMethodological/Technological Transfer in Clinical Practice

�Improvement of the medical connection

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Perspectives IPerspectives IImprovement of Ultrasound measurementsImprovement of Ultrasound measurementsImprovement of Ultrasound measurementsImprovement of Ultrasound measurements

Ponzini, Vergara, Redaelli, V., Ultrasound In Med & Biol 2006

Direct measure of flow rate in clinical practice is unfeasible

Current Ultra Sound solution:From the measure of the peak velocity to the flow rate by assuming a prabolic profile (Doucette formula, 1992):

Q=½ ρ VA

The parabolic profile assumption is quite unrealistic in vivo: this means

that US flow rate measure can be inaccurate

Measures

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Idea:To use numerical simulation in geometries reconstructed from real patients for setting up more accurate and representative formulas:

Q=Q(V,…)

Problem: the specification of a velocity profile for forcing a prescribed flow rate would induce a bias in the formula tuning.

Flow rate problems MUST be solved without prescribing a velocity profile► Lagrange multiplier approach (developed also for

reliable b.c.’s in Aneurysms)

A formula has been tuned up in this way, by performing about 200 simulations in physiological realistic situations and a non-linear regression parameter fitting

Our formula is function of the peak velocity V and the pulsatility(Womersley number W - which is easy to measure)

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Formula:

2006

2008

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Results

“In silico” test on a carotid bifurcation

Vergara, Parodi, Neglia, Ponzini, Redaelli, V., 2008

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Perspectives II

Simula

tions

&

Predic

tions

Registra

tion

Filte

ring

Stati

stics

&Da

ta Minin

g

Reconstruction

Emory Project for NSF - IGERT

Goal:

PhD Program in Image Based

Analysis and Simulation

Product:

Qualified personnel able to

-To read and understand different medical images

-To perform registration/filtering/reconstruction

-To identify landmark of a statistical analysis/data –mining

-To drive numerical simulations

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E. Haber (Math&CS - PI)

A. Veneziani (Math&CS – coPI)

E. Agichtein (Math&CS – coPI)

Math & CS Department

EPICORE

Emory Hospital

Imaging

Emory Cardiac

Toolbox

V. Vaccarino

P. Raggi

J. Oshinski

E. Garcia

V. Sunderam

CLS

Biostatistics