Influence of inversion pulse type in assessing lung-oxygen-enhancement by centrically-reordered non-slice-selective inversion-recovery half-Fourier single-shot turbo spin-echo (HASTE) sequence.
OBJECTIVE
To demonstrate the influence of inversion pulse type and inversion time for assessment of oxygen-enhancement on centrically-reordered non-slice-selective inversion-recovery (IR) half-Fourier single-shot turbo spin-echo (HASTE) sequence.


METHODS
Phantoms with and without 100% oxygen and three healthy volunteers were studied with two-dimensional (2D) centrically-reordered non-slice selective IR-HASTE sequence with either composite or block inversion-recovery pulse at increasing inversion times from 200 to 1800 msec. Signal-to-noise ratios (SNRs) of phantom, real signal differences, and relative enhancement ratios of lung parenchyma between oxygen-enhanced and non-oxygen-enhanced MR images on composite and block pulse type were statistically compared at each TI.


RESULTS
SNRs at TIs of 200 and 400 msec using the composite inversion pulse type were significantly lower than those with the block inversion pulse in the in vivo study (P < 0.05), although no significant differences were observed in the phantom study and in the in vivo study at inversion times greater than or equal to 600 msec. Real signal intensity (SI) differences at 400 and 600 msec of the composite inversion pulse type were significantly higher than those with the block inversion pulse type (P < 0.05). Relative enhancement ratio at 800 msec with the composite inversion pulse were significantly lower than that with the block inversion pulse (P < 0.05).


CONCLUSIONS
IR pulse type and inversion time have influence on assessment of oxygen-enhancement by centrically-reordered non-slice-selective IR-HASTE sequence.
Puderbach
Michael
M
Department of Radiology, Deutsches Krebsforschungszentrum, Heidelberg, Germany.
Ohno
Yoshiharu
Y
Kawamitsu
Hideaki
H
Koyama
Hisanobu
H
Takenaka
Daisuke
D
Nogami
Munenobu
M
Obara
Makoto
M
Van Cauteren
Marc
M
Kauczor
Hans-Ulrich
HU
Sugimura
Kazuro
K
D000328:Adult; D017352:Echo-Planar Imaging / Q000379:methods*; D005583:Fourier Analysis; D006339:Heart Rate; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015233:Models, Statistical; D010100:Oxygen / Q000737:chemistry / Q000378:metabolism*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D013997:Time Factors
D010100:Oxygen