title: Fast 3D (1)H MRSI of the corticospinal tract in pediatric brain.
abstract: OBJECTIVE
  To develop a (1)H magnetic resonance spectroscopic imaging (MRSI) sequence that can be used to image infants/children at 3T and by combining it with diffusion tensor imaging (DTI) tractography, extract relevant metabolic information corresponding to the corticospinal tract (CST).
  
  
  METHODS
  A fast 3D MRSI sequence was developed for pediatric neuroimaging at 3T using spiral k-space readout and dual band RF pulses (32 x 32 x 8 cm field of view [FOV], 1 cc iso-resolution, TR/TE = 1500/130, 6:24 minute scan). Using DTI tractography to identify the motor tracts, spectra were extracted from the CSTs and quantified. Initial data from infants/children with suspected motor delay (n = 5) and age-matched controls (n = 3) were collected and N-acetylaspartate (NAA) ratios were quantified.
  
  
  RESULTS
  The average signal-to-noise ratio of the NAA peak from the studies was approximately 22. Metabolite profiles were successfully acquired from the CST by using DTI tractography. Decreased NAA ratios in those with motor delay compared to controls of approximately 10% at the CST were observed.
  
  
  CONCLUSIONS
  A fast and robust 3D MRSI technique targeted for pediatric neuroimaging has been developed. By combining with DTI tractography, metabolic information from the CSTs can be retrieved and estimated. By combining DTI and 3D MRSI, spectral information from various tracts can be obtained and processed.
authors.affiliation: School of Electrical and Electronic Engineering, Yonsei University, Seoul, Korea. donghyunkim@yonsei.ac.kr
authors.forename: Dong-Hyun
authors.initials: DH
authors.lastname: Kim
authors.forename: Meng
authors.initials: M
authors.lastname: Gu
authors.forename: Charles
authors.initials: C
authors.lastname: Cunningham
authors.forename: Albert
authors.initials: A
authors.lastname: Chen
authors.forename: Fiona
authors.initials: F
authors.lastname: Baumer
authors.forename: Orit A
authors.initials: OA
authors.lastname: Glenn
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Vigneron
authors.forename: Daniel Mark
authors.initials: DM
authors.lastname: Spielman
authors.forename: Anthony James
authors.initials: AJ
authors.lastname: Barkovich
mesh_terms: D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000032:analysis; D002540:Cerebral Cortex / Q000378:metabolism* / Q000473:pathology*; D002675:Child, Preschool; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D007223:Infant; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D009069:Movement Disorders / Q000378:metabolism* / Q000473:pathology*; D010372:Pediatrics / Q000379:methods; D011522:Protons; D011712:Pyramidal Tracts / Q000378:metabolism* / Q000473:pathology*
chemical_list: D011522:Protons; D001224:Aspartic Acid; C000179:N-acetylaspartate