Spectroscopic SWIFT

Djaudat Idiyatullin, Curt Corum, Steen Moeller, Jutta Ellermann, Michael Garwood

Center for Magnetic Resonance Research (CMRR), Department of Radiology University of Minnesota Medical School, Minneapolis, Minnesota, USA

Declaration of Conflict of Interest or Relationship

Speaker Name: Idiyatullin Djaudat I have no conflicts of interest to disclose with regard to the subject matter of this presentation.



1

FM

G acq

( SWIFT

SWeep Imaging with Fourier Transformation Projection method FM pulses for the excitation Acquisition in gaps between pulse elements Sensitive to short T2

Goal of project

• Spectroscopic imaging based on SWIFT with sensitivity to broad

T

2 scale.

distribution including

T

2 in microsecond time

)

Spectroscopic projection imaging

Lauterbur, Levin and Marr, 1984 “Theory and Simulation of NMR Spectroscopic Imaging and Field Plotting by Projection Reconstruction Involving an Intrinsic Frequency Dimension”   atan  

GD

/  

Spectroscopic SWIFT

2D spatial +1D spectroscopic (hemisphere)

k



G

y

k

y

k

x

k

x

G

   

D

tan

sw

  cos    

b w



G

x 140 120 100 80 60 40 20 0 0 20 40 60

θ,

degree 80

τ

p

dw Spectroscopic SWIFT

… …

T p R



b T

w

p p R

X

Spectroscopic SWIFT- first experience

Vegetable oil + water, 2D spatial + 1D spectral oil water Y Ω

b

The total number of projections was 7748,

FOV

= 5 cm 2 , w,max = 125 kHz,

Ω

= 3 kHz

,

matrix = 90 3 , Acq time = 6 min

2D spatial + 1D spectral Four tubes with different concentration of iron-oxide (  -Fe 2 O 3 ) nanoparticles in agar 4.3 nM/L 0.086 nM/L 0.0086 nM/L 0.86 nM/L The total number of projections was 7748,

FOV

= 3 cm, matrix = 90 3 ,

b

w,max = 125 kHz,

Ω

= 18 kHz, Acq time = 65 sec

2D spatial + 1D spectral Four tubes with different concentration of iron-oxide (  -Fe 2 O 3 ) nanoparticles in agar

T

2 = 0.075ms

4.3 nM/L

T

2 = 2.5ms

0.0086 nM/L -10 -5 0 5 kHz 10 -10 -5 0 5 10 kHz

T

2 = 1.5ms

0.086 nM/L -10 -5 0 5 kHz 10

T

2 = 0.2ms

0.86 nM/L -10 -5 0 5 kHz 10

PD 3D spatial + 1D spectral Four tubes with different concentration of iron-oxide (  -Fe 2 O 3 ) nanoparticles in agar

T

2

B

0 Integral Max/Integral Frequency The total number of projections was 116928,

FOV

= 3 cm, matrix = 64 4

, b

w,max = 125 kHz,

Ω

= 18 kHz, Acq time = 15 min

Applications of spectroscopic SWIFT

• Short T2 map • Susceptibility map • B0 map • Spectroscopic imaging of metabolites

More SWIFT from CMRR 2773. Enhancing Lipid Signals with SWIFT 2672. Implementation of SWIFT on a Siemens Clinical Scanner 2864. Iterative Reconstruction for Off-Resonance Effects in SWIFT Imaging 3061. MP-SWIFT with Adiabatic Inversion Preparation for Quiet, B1..

802. SWIFT Detection of SPIO Labeled Stem Cells Grafted in the Myocardium 848. The Ultrastructure of Bone Using Selective Saturation in SWIFT at 9.4 T Acknowledgments.

NIH P41-RR008079, the Keck Foundation. MMF 3761-9236-07 Thanks to many others at the CMRR!