title: Assessment of Silent T1-weighted head imaging at 7 T.
abstract: OBJECTIVE
  This study aimed to assess the performance of a "Silent" zero time of echo (ZTE) sequence for T1-weighted brain imaging using a 7 T MRI system.
  
  
  METHODS
  The Silent sequence was evaluated qualitatively by two neuroradiologists, as well as quantitatively in terms of tissue contrast, homogeneity, signal-to-noise ratio (SNR) and acoustic noise. It was compared to conventional T1-weighted imaging (FSPGR). Adequacy for automated segmentation was evaluated in comparison with FSPGR acquired at 7 T and 1.5 T. Specific absorption rate (SAR) was also measured.
  
  
  RESULTS
  Tissue contrast and homogeneity in Silent were remarkable in deep brain structures and in the occipital and temporal lobes. Mean tissue contrast was significantly (p < 0.002) higher in Silent (0.25) than in FSPGR (0.11), which favoured automated tissue segmentation. On the other hand, Silent images had lower SNR with respect to conventional imaging: average SNR of FSPGR was 2.66 times that of Silent. Silent images were affected by artefacts related to projection reconstruction, which nevertheless did not compromise the depiction of brain tissues. Silent acquisition was 35 dB(A) quieter than FSPGR and less than 2.5 dB(A) louder than ambient noise. Six-minute average SAR was <2 W/kg.
  
  
  CONCLUSIONS
  The ZTE Silent sequence provides high-contrast T1-weighted imaging with low acoustic noise at 7 T.
  
  
  CONCLUSIONS
  • "Silent" is an MRI technique allowing zero time of echo acquisition • Its feasibility and performance were assessed on a 7 T MRI system • Image quality in several regions was higher than in conventional techniques • Imaging acoustic noise was dramatically reduced compared with conventional imaging • "Silent" is suitable for T1-weighted head imaging at 7 T.
authors: Imago7 Foundation, Calambrone, Pisa, Italy. me@maurocostagli.info.|Laboratory of Medical Physics and Biotechnologies for Magnetic Resonance, IRCCS Stella Maris, Pisa, Italy. me@maurocostagli.info.
authors: Mauro
authors: http://orcid.org/0000-0001-9073-1082
authors: M
authors: Costagli
authors: GE Applied Science Laboratory, Pisa, Italy.
authors: Mark R
authors: MR
authors: Symms
authors: Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.
authors: Lorenzo
authors: L
authors: Angeli
authors: GE Healthcare Technologies, San Francisco, CA, USA.
authors: Douglas A C
authors: DA
authors: Kelley
authors: Laboratory of Medical Physics and Biotechnologies for Magnetic Resonance, IRCCS Stella Maris, Pisa, Italy.
authors: Laura
authors: L
authors: Biagi
authors: Engineering Department, University of Ferrara, Ferrara, Italy.|Materiacustica s.r.l., Ferrara, Italy.
authors: Andrea
authors: A
authors: Farnetani
authors: Department of Physics, University of Pisa, Pisa, Italy.
authors: Catarina
authors: C
authors: Rua
authors: Neuroradiology Unit, Department of Diagnostic and Interventional Radiology, Azienda Ospedaliero-Universitaria Pisana (AOUP), Pisa, Italy.
authors: Graziella
authors: G
authors: Donatelli
authors: Imago7 Foundation, Calambrone, Pisa, Italy.|Laboratory of Medical Physics and Biotechnologies for Magnetic Resonance, IRCCS Stella Maris, Pisa, Italy.
authors: Gianluigi
authors: G
authors: Tiberi
authors: Imago7 Foundation, Calambrone, Pisa, Italy.|Laboratory of Medical Physics and Biotechnologies for Magnetic Resonance, IRCCS Stella Maris, Pisa, Italy.
authors: Michela
authors: M
authors: Tosetti
authors: Imago7 Foundation, Calambrone, Pisa, Italy.|Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.
authors: Mirco
authors: M
authors: Cosottini
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016477:Artifacts; D001921:Brain / Q000000981:diagnostic imaging*; D005260:Female; D005544:Forecasting; D064368:Healthy Volunteers; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D059629:Signal-To-Noise Ratio; D055815:Young Adult
keywords: Brain; Magnetic resonance imaging; Neuroimaging; Patient satisfaction; Technology assessment, Biomedical