J Korean Soc Radiol.  2013 Apr;68(4):355-362. 10.3348/jksr.2013.68.4.355.

Impact of the Parameter Variation on the Image Blurring in 3 T Magnetic Resonance Imaging: A Phantom Study

• Kim JW
• Lee SH
• Kim N
• Cho KS
• Lee JS

• KMID: 1425154
• DOI: http://doi.org/10.3348/jksr.2013.68.4.355

Abstract

PURPOSE
To evaluate the effects of the key imaging-parameter alterations on the four MR sequences in a phantom study.
MATERIALS AND METHODS
Magnetic resonance (MR) imaging was performed on a MR phantom with an 8-channel head coil by using a 3 T MR system. The images were obtained in the axial plane on four MR sequences [T1-weighted, T2-weighted, Proton-density, and 3 dimensional (3D) fast spin echo (FSE)] with controlled variations in the following key parameters: 1) echo train length (ETL), 2) repetition time (TR), and 3) echo time (TE). The image blurring was determined by the degree of the gradient angle; i.e., the blurring increased as the gradient angle decreases.
RESULTS
The increasing ETL was observed to cause an increase in the image blurring on all pulse sequences with a statistical significance (p = 0.004) on the 3D FSE. Increasing the TR appeared to have no effect except a statistically significant decrease on the T1-weighted images (p = 0.011). Increasing TE showed no effect on the T1-weighted images (p = 0.932); however, it caused an increase of blurring on the proton density images (p = 0.016) as well as the T2-weighted images (p < 0.001), and a decrease on the 3D FSE (p = 0.001).
CONCLUSION
To reduce the image blurring, short ETL and long TE for 3D FSE, long TR for T1-weighted images and short TE for proton-density and T2-weighted images should be applied.

MeSH Terms

Head
Magnetic Resonance Imaging
Magnetic Resonance Spectroscopy
Magnetics
Magnets
Protons
Protons

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