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Improved Vascular Transport Function Characterization in DSC-MRI via Deconvolution with Dispersion-Compliant Bases

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https://hal.inria.fr/hal-01358775

Submitted on 1 Sep 2016

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Improved Vascular Transport Function Characterization in DSC-MRI via Deconvolution with

Dispersion-Compliant Bases

Marco Pizzolato, Rutger Fick, Timothé Boutelier, Rachid Deriche

To cite this version:

Marco Pizzolato, Rutger Fick, Timothé Boutelier, Rachid Deriche. Improved Vascular Transport Function Characterization in DSC-MRI via Deconvolution with Dispersion-Compliant Bases. ISMRM 2016, May 2016, Singapore, Singapore. �hal-01358775�

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5

Experiments in silico

We use bases6 precisely designed to recover the effective residue function by means of deconvolution: linear estimation, positive

solution of R*.

6

Right

occlusion

Given the arterial input and tissular output, estimate the residue

function in the presence of dispersion via deconvolution.

We want to estimate R(t) and VTF(t). We use CPI+VTF4 (a non-linear VTF model-based approach) that assumes VTF(t)=gamma(t,P,S), so the problem reduces to find R(t), P (time-to-peak) and S (sharpness).

CPI+VTF

R

DCB

*

(t)

(

+

)

Dispersion-Compliant Bases

a

1,2,..,N

b

1,2,..,N

We generate data with different Dispersion Kernels (gamma, exponential, lognormal) and dispersion intensity (low, medium, high). CBF P S CBF P S CBF P S CBF P S time to peak

CBF

S

P

CPI+VTF

Proposed

DCB

preprocessing

No assumptions on VTF

R(t),P,S

Gamma Distribution Parameters We want to improve the estimation of the VTF gamma model

parameters, P and S, compared to the standard approach.

drawing

inspired by [4]

ISMRM 2016, May 7-13, Singapore

# 1474

Bolus dispersion affects the residue function computed via deconvolution of DSC-MRI data. The obtained effective residue

function can be expressed as the convolution of the true one with a Vascular Transport Function (VTF) that characterizes

dispersion. The state-of-the-art technique CPI+VTF allows to estimate the actual residue function by assuming a model of VTF.

We propose to perform deconvolution representing the effective residue function with Dispersion-Compliant Bases (DCB) with

no assumptions on the VTF, and then apply the CPI+VTF on DCB results, to improve performance.

1

Perfusion problem & Dispersion

Dispersion

= ?

?

VTF

C

ts

(t)

Tissular output

C

a

(t)

Arterial input

e

ective

r

esidue fun

ction

Actual Residue function Vascular Transport Function

R

*

(t)

No Dispersion

R

*

(t)

DCB improve the

est-imation of effective parameters, such as CBF*, MTT*, TTP.

DCB allow to better

recover the Cerebral

Blood Flow and the

VTF (P,S).

effective residue function

R

*

Athena Project Team , Inria Sophia Antipolis - Méditerranée, France

Olea Medical, La Ciotat, France

Contact: marco.pizzolato@inria.fr, url: http://www-sop.inria.fr/athena

Improved Vascular Transport Function Characterization in

DSC-MRI via Deconvolution with Dispersion-Compliant Bases

Marco Pizzolato

*

, Rutger Fick

*

, Timothé Boutelier

& Rachid Deriche

*

4

DCB preprocessing for CPI+VTF

unit step function; maximum basis order;

,

coefficients; expected MTT;

C

ts

(t)

C

a

(t)

Arterial input

?

DCB deconvolution Tissular output model fitting

References

[1] Calamante et al. 2000, Magn Reson Med, vol. 44(3), 466–473; [2] Calamante et al. 2003, NeuroImage, vol. 19, 341–353; [3] Willats et al. 2006, Magn Reson Med, 146–156; [4] Mehndiratta et al. 2013, Magn Reson Med, vol. 72, 1486- 1491; [5] Wu et al. 2003, Magn Reson Med, vol. 50(1), 164–174; [6] Pizzolato et al. 2015, ISBI, IEEE, 1073–1076.

The authors express their thanks to Olea Medical and the Provence-Alpes-Côte d’Azur Regional Council for providing grant and support.

2

Problem statement

3

Our approach: DCB

gamma(t,P,S)

t

R

*

(t) =

Control

Point

Interpolation

R

VTF

Recovering R*

Recovering R (CBF) and VTF (P,S)

t

Références

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