Three-Dimensional Modeling of Ultrasound Cancer Imaging Mohammad - - PowerPoint PPT Presentation

▶

Jan 01, 2024 221 likes •457 views

Three-Dimensional Modeling of Ultrasound Cancer Imaging Mohammad Daoud Introduction High-frequency (20-60 MHz) ultrasound imaging can be used to track tumour growth in preclinical cancer research N N 1 mm K. C. Graham et. al. , Cancer Res.

SLIDE 1

Three-Dimensional Modeling of Ultrasound Cancer Imaging

Mohammad Daoud

SLIDE 2

Introduction

K. C. Graham et. al., Cancer Res. 65:5231–5237 (2005).

High-frequency (20-60 MHz) ultrasound imaging can be used to track tumour growth in preclinical cancer research

1 mm N N

SLIDE 3

Motivation

Tumour size and shape

SLIDE 4

Motivation

Additional information about tumour microstructure

SLIDE 5

Outline

Develop a parallel three-dimensional (3D) ultrasound simulator Develop a 3D computational model of tissue microanatomy Use the ultrasound simulator and the tissue model to simulate ultrasound imaging of animal cancer models

SLIDE 6

The First-Order k-Space Method

Tabei et al. presented a two-dimensional (2D) k-space method1 based on coupled first-order wave equations The first-order k-space method incorporates frequency- dependent absorption

1M. Tabei et al., J. Acoust. Soc. Am. 111:53-63 (2002).

) , ( ) ( ) ( 1 ) , ( ) ( 1

2 2 2

               t t r p r c r t r p r   t t r u r t r p      ) , ( ) ( ) , (  t t r p r c r t r u       ) , ( ) ( ) ( 1 ) , (





SLIDE 7

Spatial derivative evaluation Temporal derivative evaluation

The First-Order k-Space Method

)} , , ( { ) , , ( t y x ik x t y x

  F F         

t t t y x t y x t t y x        ) , , ( ) , , ( ) , , (   

)} , , ( { ) , , ( t y x ik y t y x

  F F         

SLIDE 8

)}} , , ( { ) 2 / ( sinc { ) , , (

1 ) ( 0

t y x ik tk c x t y x

x t c

  F F    

 

)}} , , ( { ) 2 / ( sinc { ) , , (

1 ) ( 0

t y x ik tk c y t y x

y t c

  F F    

 

Spatial derivative evaluation + temporal correction term

k-space propagation operator

The First-Order k-Space Method

Correction term Fourier transform of spatial derivative

SLIDE 9

The first-order k-space method is extended to compute 3D acoustic propagation The 3D k-space method is implemented to run on distributed-memory computer clusters

Enabling 3D Imaging Simulations

Propagation medium Ultrasound transducer

ny nx nz

Processor 1 Processor m-1 Processor m nx ny

SLIDE 10

B-Mode Imaging Simulations

Fat Connective tissue Water

The incident pulse has a Gaussian envelope, a center frequency of 40 MHz, and −6-dB bandwidth of 24 MHz

y x z

SLIDE 11

B-Mode Imaging Simulations

SLIDE 12

B-Mode Imaging Simulations

Scale bar = 0.5 mm Serial simulation time: 357.5 hours Parallel simulation time (20 processors): 18.6 hours

SLIDE 13

Tissue Computational Model

Nucleus Cytoplasm Extracellular matrix

SLIDE 14

Modeled Structural Properties

Nuclear volume fraction: nuclei volumes divided by total tissue volume Nuclear size distribution: histogram of the nuclei diameters Ratio of cell diameter to nucleus diameter Spatial organization of cells: descriptors of the 3D spatial organization of nuclei in tissue

SLIDE 15

Simulated Tissue vs. DAPI - Healthy Tissue

30µ 30µ

SLIDE 16

Simulated Tissue vs. DAPI - Tumour Tissue

30µ 30µ 30µ 30µ

SLIDE 17

Experimental Ultrasound Imaging

VisualSonics Vevo 770

Center frequency: 40 MHz
−6-dB bandwidth: 80%
Resolution: 40 × 80 × 80 µm3

www.visualsonics.com

SLIDE 18

Experimental Ultrasound Imaging

SLIDE 19

Simulated vs. Experimental Images - Healthy Tissue

Simulated B-mode image Experimental B-mode image Scale bar = 94 µm

SLIDE 20

Gray Level Histogram of Healthy Tissue

SLIDE 21

Simulated vs. Experimental Images - Tumour Tissue

Simulated B-mode image Experimental B-mode image Scale bar = 94 µm

SLIDE 22

Gray Level Histogram of Tumour Tissue