title: Improved spatial coverage for brain 3D PRESS MRSI by automatic placement of outer-volume suppression saturation bands.
abstract: OBJECTIVE
  To develop a technique for optimizing coverage of brain 3D (1) H magnetic resonance spectroscopic imaging (MRSI) by automatic placement of outer-volume suppression (OVS) saturation bands (sat bands) and to compare the performance for point-resolved spectroscopic sequence (PRESS) MRSI protocols with manual and automatic placement of sat bands.
  
  
  METHODS
  The automated OVS procedure includes the acquisition of anatomic images from the head, obtaining brain and lipid tissue maps, calculating optimal sat band placement, and then using those optimized parameters during the MRSI acquisition. The data were analyzed to quantify brain coverage volume and data quality.
  
  
  RESULTS
  3D PRESS MRSI data were acquired from three healthy volunteers and 29 patients using protocols that included either manual or automatic sat band placement. On average, the automatic sat band placement allowed the acquisition of PRESS MRSI data from 2.7 times larger brain volumes than the conventional method while maintaining data quality.
  
  
  CONCLUSIONS
  The technique developed helps solve two of the most significant problems with brain PRESS MRSI acquisitions: limited brain coverage and difficulty in prescription. This new method will facilitate routine clinical brain 3D MRSI exams and will be important for performing serial evaluation of response to therapy in patients with brain tumors and other neurological diseases.
authors: Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA. eugene.ozhinsky@ucsf.edu
authors: Eugene
authors: E
authors: Ozhinsky
authors: Daniel B
authors: DB
authors: Vigneron
authors: Sarah J
authors: SJ
authors: Nelson
mesh_terms: D000465:Algorithms; D001331:Automation; D001921:Brain / Q000473:pathology; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000473:pathology*; D003287:Contrast Media / Q000494:pharmacology; D003952:Diagnostic Imaging / Q000379:methods; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D015233:Models, Statistical; D015203:Reproducibility of Results; D013053:Spectrophotometry / Q000379:methods
chemical_list: D003287:Contrast Media