Tripled Readout Slices in Multi Time-Point pCASL Using Multiband Look-Locker EPI

Area of Science:

• Magnetic Resonance Imaging
• Neuroimaging
• Biomedical Engineering

Background:

• Multi time-point pseudo-continuous arterial spin labelling (pCASL) with Look-Locker EPI enables blood kinetics analysis.
• Signal relaxation limits the number of slices in conventional pCASL.
• Efficiently sampling blood kinetics is crucial for quantitative perfusion imaging.

Purpose of the Study:

• To implement and evaluate a multiband excitation technique for accelerating multi time-point pCASL.
• To increase the number of readout slices in multi time-point pCASL without extending acquisition time.

Main Methods:

• Incorporation of multiband excitation and 2-fold in-plane parallel imaging into Look-Locker EPI for pCASL.
• Performance comparison between multiband and single-band techniques in four healthy subjects at 3T.
• Analysis of quantitative perfusion maps derived from labelling with and without flow suppression gradients.

Main Results:

• Multiband accelerated pCASL successfully tripled readout slices (18 vs. 6) within the same acquisition time (6.23 min).
• Perfusion maps from the multiband technique showed good agreement with the conventional single-band method.
• Multiband acceleration resulted in a minor SNR loss but maintained quantitative accuracy.

Conclusions:

• Multiband excitation is a viable technique to enhance volumetric coverage in multi time-point pCASL.
• This acceleration allows for comparable quantitative perfusion data acquisition in significantly reduced time.
• The method holds promise for improving the efficiency of dynamic perfusion imaging.