Intracranial circulation: pulse-sequence considerations in three-dimensional (volume) MR angiography

Area of Science:

• Radiology
• Medical Imaging
• Neuroscience

Background:

• Intracranial vessel imaging is crucial for diagnosing neurological conditions.
• Magnetic Resonance (MR) angiography offers non-invasive visualization of blood vessels.
• Optimizing MR angiography techniques is essential for accurate depiction of cerebral vasculature.

Purpose of the Study:

• To evaluate the technique and feasibility of MR angiography for intracranial vessels.
• To determine the effects of sequence parameters on flow-related enhancement.
• To investigate gradient modifications for reducing motion artifacts in brain imaging.

Main Methods:

• Studied 35 healthy volunteers using magnetic resonance (MR) angiography.
• Evaluated variations in image orientation, repetition time (TR), and flip angle.
• Assessed gradient modifications including echo time (TE), motion compensation, bandwidth, and field of view.

Main Results:

• A fast imaging with steady precession (FISP) sequence with specific parameters (TR 50 msec, TE 15 msec, velocity/acceleration compensation, anisotropic volume, 1.25-mm partition thickness) yielded accurate and reproducible 3D MR angiographic images.
• The optimized technique successfully depicted major intracranial vessels.
• Challenges remain with field of view limitations, signal voids from motion, and spatial resolution.

Conclusions:

• Optimized FISP MR angiography is a feasible and accurate method for visualizing intracranial vessels.
• Further research is needed to address limitations in field of view, motion artifacts, and spatial resolution for improved brain imaging.
• This technique holds promise for non-invasive neurovascular assessment.