Volumetric fat-water separated T2-weighted MRI.
BACKGROUND
Pediatric body MRI exams often cover multiple body parts, making the development of broadly applicable protocols and obtaining uniform fat suppression a challenge. Volumetric T2 imaging with Dixon-type fat-water separation might address this challenge, but it is a lengthy process.


OBJECTIVE
We develop and evaluate a faster two-echo approach to volumetric T2 imaging with fat-water separation.


METHODS
A volumetric spin-echo sequence was modified to include a second shifted echo so two image sets are acquired. A region-growing reconstruction approach was developed to decompose separate water and fat images. Twenty-six children were recruited with IRB approval and informed consent. Fat-suppression quality was graded by two pediatric radiologists and compared against conventional fat-suppressed fast spin-echo T2-W images. Additionally, the value of in- and opposed-phase images was evaluated.


RESULTS
Fat suppression on volumetric images had high quality in 96% of cases (95% confidence interval of 80-100%) and were preferred over or considered equivalent to conventional two-dimensional fat-suppressed FSE T2 imaging in 96% of cases (95% confidence interval of 78-100%). In- and opposed-phase images had definite value in 12% of cases.


CONCLUSIONS
Volumetric fat-water separated T2-weighted MRI is feasible and is likely to yield improved fat suppression over conventional fat-suppressed T2-weighted imaging.
Department of Radiology, Stanford University, Lucile Packard Children's Hospital, Palo Alto, CA 94304, USA. vasanawala@stanford.edu
Shreyas S
SS
Vasanawala
Ananth J
AJ
Madhuranthakam
Ramesh
R
Venkatesan
Arvind
A
Sonik
Peng
P
Lai
Anja C S
AC
Brau
D000273:Adipose Tissue; D000293:Adolescent; D001834:Body Water; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D051598:Whole Body Imaging
Magn Reson Med. 2003 Mar;49(3):527-35
12594756
Magn Reson Med. 2004 Aug;52(2):415-9
15282827
Magn Reson Med. 2008 Sep;60(3):640-9
18727082
J Magn Reson Imaging. 2006 Jan;23(1):36-41
16315212
Radiology. 1984 Oct;153(1):189-94
6089263
Radiology. 1994 Aug;192(2):555-61
8029431
Phys Med Biol. 1985 Apr;30(4):341-4
4001160
Invest Radiol. 2005 Dec;40(12):754-60
16304477
Magn Reson Med. 2005 Sep;54(3):636-44
16092103
J Magn Reson Imaging. 2010 Sep;32(3):745-51
20815077
J Magn Reson Imaging. 1993 Nov-Dec;3(6):894-9
8280980
J Magn Reson Imaging. 2010 Jan;31(1):4-18
20027567
J Magn Reson Imaging. 1997 Nov-Dec;7(6):1002-15
9400843
Magn Reson Med. 1991 Apr;18(2):371-83
2046518
J Magn Reson Imaging. 1995 Mar-Apr;5(2):181-5
7766980
J Comput Assist Tomogr. 1985 Nov-Dec;9(6):1084-9
4056142
J Magn Reson Imaging. 2008 Sep;28(3):543-58
18777528
Magn Reson Med. 1990 Aug;15(2):287-304
2392053