MR angiography of the pelvis with variable velocity encoding and a phased-array coil

Area of Science:

• Radiology
• Medical Imaging
• Cardiovascular Imaging

Background:

• Magnetic resonance angiography (MRA) is crucial for visualizing pelvic vasculature.
• Phase-contrast (PC) sequences are commonly used for MRA, but optimizing signal-to-noise ratio (S/N) and vessel depiction remains a challenge.

Purpose of the Study:

• To assess the feasibility of an automated variable velocity-encoding sequence for MRA.
• To enhance S/N in pelvic MRAs using phase contrast and a phased-array coil.

Main Methods:

• Evaluated three cardiac-gated, 2D PC sequences in 10 healthy subjects.
• Compared a variable velocity encoding sequence (VOPC) against constant velocity encoding sequences.
• Assessed S/N of VOPC images acquired with a pelvic phased-array coil versus a body coil.

Main Results:

• VOPC was preferred for simultaneous visualization of large and small pelvic vessels.
• VOPC demonstrated superior overall image interpretation compared to constant velocity encoding.
• Pelvic phased-array coil with VOPC yielded 68%-100% higher S/N than the body coil.

Conclusions:

• Variable velocity encoding combined with a phased-array coil improves pelvic MRA.
• This approach enhances the depiction of segmental vascular anatomy in the pelvis.
• Feasibility of automated variable velocity encoding is demonstrated for improved pelvic vascular imaging.