Skip to main content
Log in

Assessment of Silent T1-weighted head imaging at 7 T

  • Magnetic Resonance
  • Published:
European Radiology Aims and scope Submit manuscript

Abstract

Objectives

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.

Key Points

“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

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others

Abbreviations

MRI:

Magnetic resonance imaging

TE:

Time of echo

TI:

Time of inversion

TD:

Time of delay

ZTE:

Zero time of echo

SNR:

Signal-to-noise ratio

FSPGR:

Fast spoiled gradient-recalled

ROI:

Region of interest

WM:

White matter

GM:

Gray matter

TC:

Tissue contrast

WMIV:

White matter intensity variability

GMCR:

Gray matter cortical ribbon

OT:

Other tissues

SAR:

Specific absorption rate

TPR:

True-positive rate (sensitivity)

SPC:

Specificity

PPV:

Positive predictive value (precision)

NPV:

Negative predictive value

References

  1. Bergin CJ, Pauly JM, Macovski A (1991) Lung parenchyma: projection reconstruction MR imaging. Radiology 179:777–781

    Article  CAS  PubMed  Google Scholar 

  2. Madio DP, Lowe IJ (1995) Ultra‐fast imaging using low flip angles and fids. Magn Reson Med 34:525–529

    Article  CAS  PubMed  Google Scholar 

  3. Idiyatullin D, Corum C, Park J-Y, Garwood M (2006) Fast and quiet MRI using a swept radiofrequency. J Magn Reson 181:342–349

    Article  CAS  PubMed  Google Scholar 

  4. Wu Y, Dai G, Ackerman JL et al (2007) Water- and fat-suppressed proton projection MRI (WASPI) of rat femur bone. Magn Reson Med 57:554–567

    Article  PubMed  Google Scholar 

  5. Tyler DJ, Robson MD, Henkelman RM et al (2007) Magnetic resonance imaging with ultrashort TE (UTE) PULSE sequences: Technical considerations. J Magn Reson Imaging 25:279–289

    Article  PubMed  Google Scholar 

  6. Du J, Bydder M, Takahashi AM, Chung CB (2008) Two-dimensional ultrashort echo time imaging using a spiral trajectory. Magn Reson Imaging 26:304–312

    Article  PubMed  Google Scholar 

  7. Qian Y, Boada FE (2008) Acquisition‐weighted stack of spirals for fast high‐resolution three‐dimensional ultra‐short echo time MR imaging. Magn Reson Med 60:135–145

    Article  PubMed  Google Scholar 

  8. Du J, Bydder M, Takahashi AM et al (2011) Short T2 contrast with three-dimensional ultrashort echo time imaging. Magn Reson Imaging 29:470–482

    Article  PubMed  PubMed Central  Google Scholar 

  9. Weiger M, Pruessmann KP, Hennel F (2011) MRI with zero echo time: hard versus sweep pulse excitation. Magn Reson Med 66:379–389

    Article  PubMed  Google Scholar 

  10. Weiger M, Brunner DO, Dietrich BE et al (2013) ZTE imaging in humans. Magn Reson Med 70:328–332

    Article  PubMed  Google Scholar 

  11. Grodzki DM, Jakob PM, Heismann B (2012) Ultrashort echo time imaging using pointwise encoding time reduction with radial acquisition (PETRA). Magn Reson Med 67:510–518

    Article  PubMed  Google Scholar 

  12. Johnson KM, Fain SB, Schiebler ML, Nagle S (2013) Optimized 3D ultrashort echo time pulmonary MRI. Magn Reson Med 70:1241–1250

    Article  PubMed  PubMed Central  Google Scholar 

  13. Weiger M, Stampanoni M, Pruessmann KP (2013) Direct depiction of bone microstructure using MRI with zero echo time. Bone 54:44–47

    Article  PubMed  Google Scholar 

  14. Weiger M, Hennel F, Pruessmann KP (2010) Sweep MRI with algebraic reconstruction. Magn Reson Med 64:1685–1695

    Article  PubMed  Google Scholar 

  15. Heilmaier C, Theysohn JM, Maderwald S et al (2011) A large-scale study on subjective perception of discomfort during 7 and 1.5 T MRI examinations. Bioelectromagnetics 32:610–619

    Article  PubMed  Google Scholar 

  16. Cosottini M, Frosini D, Biagi L et al (2014) Short-term side-effects of brain MR examination at 7 T: a single-centre experience. Eur Radiol 24:1923–1928

    Article  CAS  PubMed  Google Scholar 

  17. Glover GH, Pauly JM (1992) Projection reconstruction techniques for reduction of motion effects in MRI. Magn Reson Med 28:275–289

    Article  CAS  PubMed  Google Scholar 

  18. Madio DP, Gach HM, Lowe IJ (1998) Ultra-fast velocity imaging in stenotically produced turbulent jets using RUFIS. Magn Reson Med 39:574–580

    Article  CAS  PubMed  Google Scholar 

  19. Kelley DAC, McKinnon GC, Sacolick LI et al (2014) Optimization of a Zero Echo Time (ZTE) Sequence at 7T with Phased Array Coils. Proceedings of International Society for Magnetic Resonance in Medicine ISMRM

    Google Scholar 

  20. Weiger M, Brunner DO, Wyss M et al (2014) ZTE Imaging with T1 Contrast. Proceedings of International Society for Magnetic Resonance in Medicine ISMRM

    Google Scholar 

  21. Hurley AC, Al-Radaideh A, Bai L et al (2010) Tailored RF pulse for magnetization inversion at ultrahigh field. Magn Reson Med 63:51–58

    PubMed  Google Scholar 

  22. Wrede KH, Johst S, Dammann P et al (2012) Caudal image contrast inversion in MPRAGE at 7 Tesla: problem and solution. Acad Radiol 19:172–178

    Article  PubMed  Google Scholar 

  23. O'Brien KR, Magill AW, Delacoste J et al (2014) Dielectric pads and low- B1+ adiabatic pulses: complementary techniques to optimize structural T1 w whole-brain MP2RAGE scans at 7 tesla. J Magn Reson Imaging 40:804–812

    Article  PubMed  Google Scholar 

  24. Belaroussi B, Milles J, Carme S et al (2006) Intensity non-uniformity correction in MRI: existing methods and their validation. Med Image Anal 10:234–246

    Article  PubMed  Google Scholar 

  25. Van de Moortele P-F, Akgun C, Adriany G et al (2005) B(1) destructive interferences and spatial phase patterns at 7 T with a head transceiver array coil. Magn Reson Med 54:1503–1518

    Article  PubMed  Google Scholar 

  26. Vaughan JT, Garwood M, Collins CM et al (2001) 7T vs. 4T: RF power, homogeneity, and signal-to-noise comparison in head images. Magn Reson Med 46:24–30

    Article  CAS  PubMed  Google Scholar 

  27. Dietrich O, Raya JG, Reeder SB et al (2007) Measurement of signal‐to‐noise ratios in MR images: Influence of multichannel coils, parallel imaging, and reconstruction filters. J Magn Reson Imaging 26:375–385

    Article  PubMed  Google Scholar 

  28. Tannús A, Garwood M (1997) Adiabatic pulses. NMR Biomed 10:423–434

    Article  PubMed  Google Scholar 

  29. Sacolick LI, Wiesinger F, Hancu I, Vogel MW (2010) B1 mapping by Bloch-Siegert shift. Magn Reson Med 63:1315–1322

    Article  PubMed  PubMed Central  Google Scholar 

  30. Kelley DAC, McKinnon GC, Sacolick LI et al (2014) Depiction of Multiple Sclerosis Lesions with Zero Echo Time (ZTE) Imaging at 7T. Proceedings of International Society for Magnetic Resonance in Medicine ISMRM

    Google Scholar 

  31. Tourdias T, Saranathan M, Levesque IR et al (2014) Visualization of intra-thalamic nuclei with optimized white-matter-nulled MPRAGE at 7T. NeuroImage 84:534–545

    Article  PubMed  PubMed Central  Google Scholar 

  32. Costagli M, Kelley DAC, Symms MR et al (2014) Tissue Border Enhancement by inversion recovery MRI at 7.0 Tesla. Neuroradiology 56:517–523

    Article  PubMed  Google Scholar 

  33. De Ciantis A, Barkovich AJ, Cosottini M et al (2015) Ultra-high-field MR imaging in polymicrogyria and epilepsy. AJNR Am J Neuroradiol 36:309–316

    Article  PubMed  Google Scholar 

  34. Pusey E, Lufkin RB, Brown RK et al (1986) Magnetic resonance imaging artifacts: mechanism and clinical significance. Radiographics 6:891–911

    Article  CAS  PubMed  Google Scholar 

  35. Van de Moortele P-F, Auerbach EJ, Olman C et al (2009) T1 weighted brain images at 7 Tesla unbiased for Proton Density, T2 contrast and RF coil receive B1 sensitivity with simultaneous vessel visualization. NeuroImage 46:432–446

    Article  PubMed  PubMed Central  Google Scholar 

  36. Dale AM, Fischl B, Sereno MI (1999) Cortical surface-based analysis. I. Segmentation and surface reconstruction. NeuroImage 9:179–194

    Article  CAS  PubMed  Google Scholar 

  37. Fischl B, Sereno MI, Dale AM (1999) Cortical surface-based analysis. II: Inflation, flattening, and a surface-based coordinate system. NeuroImage 9:195–207

    Article  CAS  PubMed  Google Scholar 

  38. Ueno K, Cheng K (2014) Model-Free Spatial Intensity Non-Uniformity Correction Algorithm for MR Images. Proceedings of International Society for Magnetic Resonance in Medicine ISMRM

    Google Scholar 

  39. Jenkinson M, Bannister P, Brady M, Smith S (2002) Improved optimization for the robust and accurate linear registration and motion correction of brain images. NeuroImage 17:825–841

    Article  PubMed  Google Scholar 

  40. Klauschen F, Goldman A, Barra V et al (2009) Evaluation of automated brain MR image segmentation and volumetry methods. Hum Brain Mapp 30:1310–1327

    Article  PubMed  Google Scholar 

  41. Jenkinson M, Beckmann CF, Behrens TEJ et al (2012) FSL. NeuroImage 62:782–790

    Article  PubMed  Google Scholar 

  42. van Osch MJP, Webb AG (2014) Safety of ultra-high field MRI: what are the specific risks? Curr Radiol Rep 2:1–8

    Google Scholar 

  43. Marques JP, Kober T, Krueger G et al (2010) MP2RAGE, a self bias-field corrected sequence for improved segmentation and T1-mapping at high field. NeuroImage 49:1271–1281

    Article  PubMed  Google Scholar 

  44. Nishimura DG (1990) Time‐of‐flight MR angiography. Magn Reson Med 14:194–201

    Article  CAS  PubMed  Google Scholar 

  45. Ashburner J, Friston KJ (2000) Voxel-based morphometry--the methods. NeuroImage 11:805–821

    Article  CAS  PubMed  Google Scholar 

  46. Whitwell JL (2009) Voxel-based morphometry: an automated technique for assessing structural changes in the brain. J Neurosci 29:9661–9664

    Article  CAS  PubMed  Google Scholar 

  47. Fischl B, Rajendran N, Busa E et al (2008) Cortical folding patterns and predicting cytoarchitecture. Cereb Cortex 18:1973–1980

    Article  PubMed  PubMed Central  Google Scholar 

  48. Gatehouse PD, Bydder GM (2003) Magnetic resonance imaging of short T2 components in tissue. Clin Radiol 58:1–19

    Article  CAS  PubMed  Google Scholar 

  49. Pruessmann KP, Weiger M, Scheidegger MB, Boesiger P (1999) SENSE: sensitivity encoding for fast MRI. Magn Reson Med 42:952–962

    Article  CAS  PubMed  Google Scholar 

  50. Griswold MA, Jakob PM, Heidemann RM et al (2002) Generalized autocalibrating partially parallel acquisitions (GRAPPA). Magn Reson Med 47:1202–1210

    Article  PubMed  Google Scholar 

  51. Tiberi G, Costagli M, Stara R, Cosottini M (2013) Electromagnetic characterization of an MR volume coil with multilayered cylindrical load using a 2-D analytical approach. J Magn Reson 230:186–197

    Article  CAS  PubMed  Google Scholar 

  52. Tiberi G, Fontana N, Costagli M et al (2015) Investigation of maximum local specific absorption rate in 7 T magnetic resonance with respect to load size by use of electromagnetic simulations. Bioelectromagnetics 36:358–366

    Article  PubMed  Google Scholar 

Download references

Acknowledgments

The scientific guarantor of this publication is Mirco Cosottini. Authors #2 and #4 of this manuscript declare relationships with the following companies: GE Healthcare. This study has received funding by the Italian Ministry of Health and the Health Service of Tuscany (RF-2009-1546281), and by the FP7 Marie Curie Actions of the European Commission (FP7-PEOPLE-2012-ITN-316716). No complex statistical methods were necessary for this paper. Institutional review board approval was obtained. Written informed consent was obtained from all subjects in this study. Methodology: assessment/evaluation of technique, performed at one institution.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Mauro Costagli.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Costagli, M., Symms, M.R., Angeli, L. et al. Assessment of Silent T1-weighted head imaging at 7 T. Eur Radiol 26, 1879–1888 (2016). https://doi.org/10.1007/s00330-015-3954-2

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00330-015-3954-2

Keywords

Navigation