Korean J Radiol.  2010 Feb;11(1):19-24. 10.3348/kjr.2010.11.1.19.

Fluid Attenuated Inversion Recovery (FLAIR) Imaging of the Normal Brain: Comparisons between Under the Conditions of 3.0 Tesla and 1.5 Tesla

• Sohn CH
• Sevick RJ
• Frayne R
• Chang HW
• Kim SP
• Kim DK

• KMID: 1787010
• DOI: http://doi.org/10.3348/kjr.2010.11.1.19

Abstract

OBJECTIVE
The aim of this study was to evaluate the differences in normal brain MRI findings between under 3.0 Tesla (T) and 1.5T MRI conditions with the use of the fluid attenuated inversion recovery (FLAIR) sequences.
MATERIALS AND METHODS
Eleven normal adults underwent imaging with the use of the FLAIR sequences on both 1.5T and 3.0T scanners. Two neuroradiologists compared the signal intensity (SI) of the centrum semiovale (CS), pulvinar thalami (PT) and normal iron deposit structures (IDSs) on the 3.0T and 1.5T FLAIR images, and they evaluated three MRI findings qualitatively: high SI of CS; low SI of PT; low SI of IDS. We also evaluated signal-to-noise ratios (SNRs) for the CS, PT, red nucleus and cerebellar dentate nucleus on the FLAIR images.
RESULTS
Based on qualitative analyses, the 3.0T FLAIR images showed all three MRI findings for all cases. Low SI for the PT in seven cases (64%), high SI of the CS in one case (9%) and low SI of the cerebellar dentate nucleus in one case (9%) were visualized only on 3.0T FLAIR images. The mean SNRs of the PT, red nucleus and dentate nucleus in patients where 3.0T FLAIR imaging was performed were significantly lower as compared with the SNRs on 1.5T FLAIR images. The SNR of the CS was not significantly different between under the two magnetic field strengths (p > 0.05).
CONCLUSION
We have demonstrated that normal, high and low SIs of the CS, PT and IDS on 3.0T FLAIR images were depicted more frequently and more prominently as compared with those on 1.5T FLAIR images in normal adult brains.

Keyword

Magnetic resonance (MR); Fluid attenuated inversion recovery (FLAIR); Normal Brain; 3.0 Tesla

MeSH Terms

Adult
Aged
Brain/*anatomy & histology
Cerebellar Nuclei/anatomy & histology
Female
Humans
Magnetic Resonance Imaging/*methods
Male
Middle Aged
Pulvinar/anatomy & histology
Red Nucleus/anatomy & histology

Figure

• 

  Fig. 1 FLAIR images of 3.0T (A, C, E) show low signal intensities at dentate nucleus of cerebellum (A) and pulvinar thalami (arrows in C) and high signal intensities at both centrum semiovales (E), but 1.5T FLAIR images (B, D, F) do not show these findings in several cases.

• 

  Fig. 2 In cases with three FLAIR MRI findings with both MR scanners, FLAIR images of 3.0T (A, C, E) show increased conspicuity of low signal intensities at dentate nucleus of cerebellum (A) and both pulvinar thalami (B) and high signal intensities at both centrum semiovales (E), as compared with 1.5T (B, D, F).

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