title: Enhancement of functional MRI signal at high-susceptibility regions of brain using simultaneous multiecho multithin-slice summation imaging technique.
abstract: To increase temporal-signal-to-noise ratio (tSNR) and blood oxygen level-dependent (BOLD) sensitivity at high-susceptibility regions of the brain by means of a simultaneous multiecho multithin-slice summation imaging technique.
  
  
  
  The simultaneous multislice (SMS) technique was implemented with multiecho (SMSME) and multiecho with thin-slice summation (SMSME-thin) at 3T. Multiecho data were summated based on the local apparent T2* weighting factor. Ten healthy subjects were studied for the whole brain activation by breath-holding. The tSNR values and the number of activated pixels acquired with SMSME and SMSME-thin were compared with those acquired with the conventional gradient-echo EPI in multiple brain regions
  
  
  
  SMS methods accelerated imaging time by 5-fold as compared with the conventional method, resulting in the acquisition of three echoes and four thin-slices during the same TR of 2.5 seconds. At high-susceptibility regions, including the amygdala, inferior and middle temporal, and anterior frontal lobes, SMSME increased tSNR values by up to ∼80% and BOLD activation by up to ∼20% (paired t-test, P < 0.05). SMSME-thin further increased values as compared with SMSME (∼45% for tSNR and ∼20% for activation, P < 0.05).
  
  
  
  The SMSME-thin imaging technique enhanced the temporal-signal-to-noise ratio and functional activation at high susceptibility regions of the brain. J. Magn. Reson. Imaging 2016;44:478-485.
authors.affiliation: Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.|Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Tae
authors.initials: T
authors.lastname: Kim
authors.affiliation: Siemens Healthcare, Siemens Medical Solution USA, Pittsburgh, Pennsylvania, USA.
authors.forename: Tiejun
authors.initials: T
authors.lastname: Zhao
authors.affiliation: Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.|Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Kyongtae T
authors.initials: KT
authors.lastname: Bae
mesh_terms: D000328:Adult; D000465:Algorithms; D001921:Brain / Q000033:anatomy & histology* / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods*; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted
keywords: blood oxygen level-dependent (BOLD); multiband; simultaneous multislice (SMS) acquisition: multiecho; thin slice