title: Fat-subtracted three-dimensional time-of-flight MR angiography of the neck by use of fat-only images with the two-point Dixon technique.
abstract: For improvement of three-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA) image quality in the neck, fat-subtracted MRA by use of the two-point Dixon technique was compared with conventional fat-suppressed MRA techniques. Three different types of neck 3D-TOF-MRA were obtained [minimum echo time (TE) (1.9 ms), opposed-phase TE (3.4 ms), and chemical shift selective fat suppression (CHESS) (TE = 1.9 ms)] on five volunteers at 3.0 T. MRA was obtained with subtraction of fat-only images (produced by a two-point Dixon sequence) from minimum-TE MRA images, and compared with other fat-suppressed MRA images. Fat-subtracted MRA demonstrated uniform fat suppression compared with other techniques. The mean vessel-to-fat contrast in fat-subtracted MRA was significantly higher (p < 0.01) than in other MRA images (minimum-TE: 0.137 ± 0.086, opposed-phase TE: 0.268 ± 0.102, CHESS: 0.307 ± 0.052, fat-subtracted: 0.965 ± 0.101). The mean vessel-to-muscle contrast in opposed-phase TE MRA was significantly lower (p < 0.01) than in other MRA images (minimum-TE: 0.526 ± 0.036, opposed-phase TE: 0.419 ± 0.188, CHESS: 0.511 ± 0.023, fat-subtracted: 0.573 ± 0.016). Fat-subtracted MRA by use of the two-point Dixon technique improves the image quality of neck MRA. This technique would be a useful method for MRA, especially in areas with inhomogeneous magnetic fields, such as the neck.
authors.affiliation: Radiological Center, University of Fukui Hospital, 23-3 Shimoaiduki, Matsuoka, Eiheiji-Cho, Yoshida-Gun, Fukui, 910-1193, Japan, yfuji@kumamoto-u.ac.jp.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Fujiwara
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Ishimori
authors.forename: Isao
authors.initials: I
authors.lastname: Yamaguchi
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Kosaka
authors.forename: Hirohiko
authors.initials: H
authors.lastname: Kimura
authors.forename: Toshiki
authors.initials: T
authors.lastname: Adachi
mesh_terms: D000273:Adipose Tissue; D000328:Adult; D005240:Feasibility Studies; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D009333:Neck; D013382:Subtraction Technique