Investig Magn Reson Imaging.  2023 Sep;27(3):121-132. 10.13104/imri.2023.0016.

Single-Slab 3D Fast Spin Echo Imaging: T₁ -Contrast Perspective

• Park J

• KMID: 2546253
• DOI: http://doi.org/10.13104/imri.2023.0016

Abstract

Fast spin echo (FSE) in magnetic resonance imaging has long been a main workhorse in clinical routines due to its versatile image contrast and robustness in improving magnetic field inhomogeneities. Nevertheless, the conventional high flip angle strategy limits its imaging efficiency, including high energy deposition to subjects, prolonged imaging time due to a necessarily short echo train, and substantial signal modulation along the echo train. Particularly, achieving high resolution T1-weighted imaging within a reasonable imaging time is challenging due to a very short echo train. In this review, we introduce T1-optimized single-slab 3D FSE imaging with variable refocusing flip angles as a promising solution to the above problems with its clinical applications. We provide a general description of a single-slab 3D pulse sequence and introduce its T1-optimized version with the required configuration of radio frequency and gradient pulses. Subsequently, the T1-weighted single-slab 3D FSE is investigated for signal evolution along the echo train, image contrasts, and flow sensitivity. Given the characteristics of high T1-weighted contrast and flow sensitivity, we demonstrate the clinical application of the single-slab 3D FSE, including high resolution structural imaging, as an alternative to conventional magnetization prepared spoiled gradient echo, highly tumor-targeted contrast-enhanced imaging for efficient detection of small metastases, and high-resolution vessel wall imaging for stroke diagnosis.

Keyword

Magnetic resonance imaging; Fast spin echo; Variable flip angles; Long echo train; Three dimensional