Rofo 2005; 177 - 12
DOI: 10.1055/s-2005-865261

Cardiac imaging at 3 Tesla: Comparison of different sequences and the use of parallel imaging at 1.5 and 3.0 T

B Spors 1, P Freyhardt 2, K Klimes 1, M Grothoff 1, R Noeske 2, R Felix 1, M Gutberlet 1
  • 1Klinik für Strahlenheilkunde, Charité Campus Virchow Klinikum, Berlin, Germany
  • 2GE Medical Systems, Berlin, Germany

Purpose: To compare image quality, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of different MRI sequences and the use of parallel imaging (ASSET) at 1.5 and 3.0 T in volunteers.

Methods: 20 volunteers were examined at a 1.5 T and 3.0 T MR scanner (GE) both using a 4-element phase array coil. We performed axial Fast Spinecho (FSE)and tagging sequences in short axis, Steady State Free Precession (SSFP) sequences in 2-chamber long and short axis with and without using ASSET. At 3.0 T the flip angle of the SSFP sequences was reduced from 45° to 30°. All other sequence parameters remained constant.

Results: Mean SNR was remarkably increased (p<0.05) in all cardiac sequences at 3.0 T. The SNR increased by 160% (T2), 123% (T1 STIR) and 91% (T1). CNR showed a similar increase. Mean SNR of SSFP sequences was more than doubled at 3.0 T (150%), without any significant effect on CNR. By using ASSET acquisition time, SNR and CNR were reduced to the same values as at 1.5T. Using the tagging sequence, the grids remained visible during diastole at 3.0 T in contrast to 1.5T.

Conclusion: Cardiac sequences at 3.0T demonstrated an increase of SNR/CNR in comparison to 1.5 T without any major changes of sequence parameters. This allows the use of parallel imaging at 3.0T with the benefit of a reduction of acquisition time and SNR values comparable to 1.5 T.