De Vita, E.;
High-resolution fast spin echo imaging of the human brain at 4.7 T: implementation and sequence characteristics.
Magnetic Resonance in Medicine
n this work, a number of important issues associated with fast spin echo (FSE) imaging of the human brain at 4.7 T are addressed. It is shown that FSE enables the acquisition of images with high resolution and good tissue contrast throughout the brain at high field strength. By employing an echo spacing (ES) of 22 ms, one can use large flip angle refocusing pulses (162°) and a low acquisition bandwidth (50 kHz) to maximize the signal-to-noise ratio (SNR). A new method of phase encode (PE) ordering (called feathering) designed to reduce image artifacts is described, and the contributions of RF (B1) inhomogeneity, different echo coherence pathways, and magnetization transfer (MT) to FSE signal intensity and contrast are investigated. B1 inhomogeneity is measured and its effect is shown to be relatively minor for high-field FSE, due to the self-compensating characteristics of the sequence. Thirty-four slice data sets (slice thickness = 2 mm; in-plane resolution = 0.469 mm; acquisition time = 11 min 20 s) from normal volunteers are presented, which allow visualization of brain anatomy in fine detail. This study demonstrates that high-field FSE produces images of the human brain with high spatial resolution, SNR, and tissue contrast, within currently prescribed power deposition guidelines.
|Title:||High-resolution fast spin echo imaging of the human brain at 4.7 T: implementation and sequence characteristics|
|Keywords:||High-field FSE, feathering, T2-weighted MRI, structural MRI, high-field MR|
|UCL classification:||UCL > School of BEAMS > Faculty of Engineering Science > Medical Physics and Bioengineering
UCL > School of Life and Medical Sciences > Faculty of Brain Sciences > Institute of Neurology > Brain Repair and Rehabilitation
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