title: Sensitivity encoding for fast (1) H MR spectroscopic imaging water reference acquisition.
abstract: OBJECTIVE
  Accurate and fast (1) H MR spectroscopic imaging (MRSI) water reference scans are important for absolute quantification of metabolites. However, the additional acquisition time required often precludes the water reference quantitation method for MRSI studies. Sensitivity encoding (SENSE) is a successful MR technique developed to reduce scan time. This study quantitatively assesses the accuracy of SENSE for water reference MRSI data acquisition, compared with the more commonly used reduced resolution technique.
  
  
  METHODS
  2D MRSI water reference data were collected from a phantom and three volunteers at 3 Tesla for full acquisition (306 s); 2× reduced resolution (64 s) and SENSE R = 3 (56 s) scans. Water amplitudes were extracted using MRS quantitation software (TARQUIN). Intensity maps and Bland-Altman statistics were generated to assess the accuracy of the fast-MRSI techniques.
  
  
  RESULTS
  The average mean and standard deviation of differences from the full acquisition were 2.1 ± 3.2% for SENSE and 10.3 ± 10.7% for the reduced resolution technique, demonstrating that SENSE acquisition is approximately three times more accurate than the reduced resolution technique.
  
  
  CONCLUSIONS
  SENSE was shown to accurately reconstruct water reference data for the purposes of in vivo absolute metabolite quantification, offering significant improvement over the more commonly used reduced resolution technique.
authors.affiliation: PSIBS Doctoral Training Centre, University of Birmingham, United Kingdom.|Department of Oncology, Birmingham Children's Hospital NHS Foundation Trust, Birmingham, United Kingdom.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Birch
authors.affiliation: Department of Oncology, Birmingham Children's Hospital NHS Foundation Trust, Birmingham, United Kingdom.|School of Cancer Sciences, University of Birmingham, United Kingdom.
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Peet
authors.affiliation: Department of Oncology, Birmingham Children's Hospital NHS Foundation Trust, Birmingham, United Kingdom.|Institute of Digital Healthcare, WMG, University of Warwick, Coventry, United Kingdom.
authors.forename: Theodoros N
authors.initials: TN
authors.lastname: Arvanitis
authors.affiliation: Department of Oncology, Birmingham Children's Hospital NHS Foundation Trust, Birmingham, United Kingdom.|School of Cancer Sciences, University of Birmingham, United Kingdom.
authors.forename: Martin
authors.initials: M
authors.lastname: Wilson
mesh_terms: D000328:Adult; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001921:Brain / Q000378:metabolism*; D001923:Brain Chemistry; D001931:Brain Mapping; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism; D064368:Healthy Volunteers; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007091:Image Processing, Computer-Assisted / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D014867:Water
chemical_list: D014867:Water; D001224:Aspartic Acid; D018698:Glutamic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline