Rapid hybrid encoding for high-resolution whole-brain fluid-attenuated imaging

Area of Science:

• Medical Imaging
• Neuroimaging
• Magnetic Resonance Imaging

Background:

• Single-slab 3D turbo spin-echo (TSE) with inversion recovery (IR) offers fluid-attenuated brain imaging for lesion detection.
• Current methods face efficiency limitations due to long inversion times required for cerebrospinal fluid (CSF) suppression.

Purpose of the Study:

• To develop a novel, rapid hybrid encoding method for highly efficient whole-brain fluid-attenuated imaging.
• To overcome the time constraints of existing techniques for improved lesion conspicuity.

Main Methods:

• A hybrid modular acquisition sequentially encodes volumetric data using reversed fast imaging with steady-state free precession (PSIF) for high spatial frequencies and VFA-TSE for low spatial frequencies.
• Identical gradient-induced spin de-phasing and a two-step RF phase-cycling scheme minimize artifacts and multiple echoes.

Main Results:

• Numerical simulations validated signal evolution and optimized parameters.
• In vivo studies demonstrated high-resolution isotropic fluid-attenuated whole-brain images acquired in clinically acceptable times.
• The technique achieved high white matter signal-to-noise ratio and maintained lesion conspicuity.

Conclusions:

• The proposed rapid hybrid encoding method significantly enhances imaging efficiency for fluid-attenuated whole-brain MRI.
• This approach enables high-quality, time-efficient neuroimaging for improved lesion detection.