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Table 1 Common IVWM pulse sequences with advantages/disadvantages

From: Intracranial vessel wall MRI: a review of current indications and future applications

Pulse sequence Advantages Disadvantages
3D time of flight (TOF) MRA (non-contrast) Flow-related enhancement allows identification of luminal abnormality or aneurysm for measurement and placement of IVWM sequences Luminal imaging alone may not identify non-stenotic vessel abnormalities (outwardly remodeling plaque, non-stenotic dissection, etc.). TOF overestimates stenosis secondary to flow dephasing artifact. It also shows diminished flow in slow flow or in-plane flow states. These are overcome with contrast-enhanced TOF MRA
2D turbo spin echo (TSE) or fast spin echo (FSE) Wide availability, good in-plane resolution, flexible tissue contrast, reduced sensitivity to magnetic field inhomogeneities, high SNR, can image focused area of interest in rapid acquisition to limit motion artifact Low spatial resolution in the slice-select direction leading to partial volume effect that can hide subtle findings, poor reproducibility, inability to create multiplanar reformats. Requires multi-planar scanning which is time consuming
3D variable refocusing flip angle (VRFA) sequences (VISTA, Philips; SPACE, Siemens; CUBE, GE) High SNR with excellent spatial resolution, superior anatomic coverage, T1/T2/PD weightings available, ability to reformat into multiplanar images that allow viewing of vessel wall, plaque, or aneurysm from any aspect. Shorter overall scan time Requires research preparation prepulse sequence for blood suppression, longer acquisition times for slab can result in motion artifact, more susceptible to magnetic field inhomogeneities
Blood suppression prepulse:
 • Double inversion-recovery
Available as a commercial pulse, negligible effect on image contrast weighting Blood-suppression difficult after contrast administration, does not work with 3D techniques
Blood suppression prepulse:
 • Motion-sensitive driven equilibrium (MSDE)
3D blood suppression technique, robust to large slab size acquisition, in-flow/outflow independent Can lead to loss of signal with T2 weighting, inability to implement 180° pulse due to high specific absorption rate, B1 inhomogeneity
Blood suppression prepulse:
 • Delay alternating with nutation for tailored excitation (DANTE)
Best blood suppression, robust to large slab size acquisition, in-flow/outflow independent, no loss of T2 signal, performs well at 7T, available on research sequences from most vendors Longer imaging time than MSDE may create artifact from vessel wall motion
Gradient-echo 3D T1-weighted without blood suppression (MP-RAGE, FLASH) Can identify intraplaque hemorrhage in atherosclerosis, intramural hematoma in dissection, and aneurysmal wall hematoma Lack of blood suppression can hide pathologic findings, unclear significance of intracranial intraplaque hemorrhage. MP-RAGE is preferred sequence