title: Amide proton transfer magnetic resonance imaging of Alzheimer's disease at 3.0 Tesla: a preliminary study.
abstract: BACKGROUND
  Amide proton transfer (APT) imaging has recently emerged as an important contrast mechanism for magnetic resonance imaging (MRI) in the field of molecular and cellular imaging. The aim of this study was to evaluate the feasibility of APT imaging to detect cerebral abnormality in patients with Alzheimer's disease (AD) at 3.0 Tesla.
  
  
  METHODS
  Twenty AD patients (9 men and 11 women; age range, 67-83 years) and 20 age-matched normal controls (11 men and 9 women; age range, 63-82 years) underwent APT and traditional MRI examination on a 3.0 Tesla MRI system. The magnetic resonance ratio asymmetry (MTR asym ) values at 3.5 ppm of bilateral hippocampi (Hc), temporal white matter regions, occipital white matter regions, and cerebral peduncles were measured on oblique axial APT images. MTR asym (3.5 ppm) values of the cerebral structures between AD patients and control subjects were compared with independent samples t-test. Controlling for age, partial correlation analysis was used to investigate the associations between mini-mental state examination (MMSE) and the various MRI measures among AD patients.
  
  
  RESULTS
  Compared with normal controls, MTR asym (3.5 ppm) values of bilateral Hc were significantly increased in AD patients (right 1.24% ± 0.21% vs. 0.83% ± 0.19%, left 1.18% ± 0.18% vs. 0.80%± 0.17%, t = 3.039, 3.328, P = 0.004, 0.002, respectively). MTR asym (3.5 ppm) values of bilateral Hc were significantly negatively correlated with MMSE (right r = -0.559, P = 0.013; left r = -0.461, P = 0.047).
  
  
  CONCLUSIONS
  Increased MTR asym (3.5 ppm) values of bilateral Hc in AD patients and its strong correlations with MMSE suggest that APT imaging could potentially provide imaging biomarkers for the noninvasive molecular diagnosis of AD.
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.forename: Sa-Ying
authors.initials: SY
authors.lastname: Li
authors.affiliation: Department of Radiology, Beijing Hospital, Beijing 100730, China.
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.forename: Jin-Yuan
authors.initials: JY
authors.lastname: Zhou
authors.forename: Dan-Tao
authors.initials: DT
authors.lastname: Peng
authors.forename: Chen
authors.initials: C
authors.lastname: Zhang
authors.forename: Yong-Ming
authors.initials: YM
authors.lastname: Dai
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male