title: Fat-suppressed T2mapping of femoral cartilage in the porcine knee joint: A comparison with conventional T2mapping.
abstract: To investigate the effect of fat suppression on T2mapping of the articular cartilage in the porcine knee joint using magnetic resonance imaging (MRI).
  
  
  
  Eleven porcine knee joints were harvested en bloc with intact capsules. We performed T2mapping of the articular cartilage in the medial femoral condyle at 3T either with (fat-suppressed T2mapping) or without (conventional T2mapping) fat suppression in the sagittal plane under two frequency-encoding directions: from superior to inferior (SI) and inferior to superior (IS). Two observers measured the T2values of the medial femoral condyle cartilage in four regions: in the anterior oblique, central horizontal, posterior oblique, and posterior vertical portions. We evaluated reproducibility of the fat-suppressed and conventional T2mapping by changing the frequency-encoding direction.
  
  
  
  The mean T2values of fat-suppressed T2mapping were significantly lower than those of conventional T2mapping for five of eight comparisons (P < 0.017). The mean T2values between fat-suppressed T2-SI and fat-suppressed T2-IS did not differ significantly in any region (P = 0.077-0.873). However, the mean T2values of conventional T2-SI were significantly lower compared with conventional T2-IS in three of the regions (P < 0.05). The intraclass correlation coefficient (ICC) between the two fat-suppressed T2maps was higher than the ICC between the two conventional T2maps (0.276-0.800 vs. -0.032-0.455) for three regions.
  
  
  
  Compared with conventional T2mapping, fat-suppressed T2mapping provides lower T2values of the articular cartilage and more reproducible results for the porcine knee joint.
  
  
  
  2 J. Magn. Reson. Imaging 2017;45:1076-1081.
authors.affiliation: Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Young Jin
authors.initials: YJ
authors.lastname: Ryu
authors.affiliation: Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Sung Hwan
authors.initials: SH
authors.lastname: Hong
authors.affiliation: Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Hyeonjin
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Ja-Young
authors.initials: JY
authors.lastname: Choi
authors.affiliation: Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Yoo
authors.affiliation: Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Yusuhn
authors.initials: Y
authors.lastname: Kang
authors.affiliation: Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Sang Joon
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Heung Sik
authors.initials: HS
authors.lastname: Kang
mesh_terms: D000273:Adipose Tissue; D000818:Animals; D002358:Cartilage, Articular / Q000000981:diagnostic imaging*; D005269:Femur / Q000000981:diagnostic imaging*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D023421:Models, Animal; D015203:Reproducibility of Results; D013552:Swine
keywords: T2 mapping; articular cartilage; chemical shift artifact; fat suppression