Modular 32-channel transceiver coil array for cardiac MRI at 7.0T.

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Radiofrequency (RF) Engineering
• Medical Device Design

Background:

• Cardiac MRI requires high spatial resolution and speed for accurate diagnosis.
• Existing MRI technology at 1.5T has limitations in achieving desired image quality and acceleration.
• Higher field strengths like 7.0T offer potential for improved signal-to-noise ratio (SNR) but pose technical challenges.

Purpose of the Study:

• To design and evaluate a novel 32-channel transceiver coil array for cardiac MRI at 7.0T.
• To assess the array's performance in terms of B1+ field homogenization, RF safety, and image quality.
• To determine the suitability of the array for accelerated, high-resolution 2D FLASH CINE imaging of the heart.

Main Methods:

• Development of a modular coil array with eight building blocks, each containing four transceiver loop elements.
• Utilized numerical simulations for B1+ field homogenization and RF safety validation.
• Conducted phantom studies to examine RF characteristics and volunteer studies for imaging performance evaluation.

Main Results:

• The 32-channel array demonstrated suitable RF characteristics and transmission field adjustments.
• Achieved a spatial resolution of 1.1 × 1.1 × 2.5 mm³ for 2D CINE FLASH MRI, a six-fold improvement over 1.5T clinical protocols.
• Supported one-dimensional acceleration factors up to R=4 without significant image quality degradation.

Conclusions:

• The modular 32-channel transceiver cardiac array facilitates accelerated and high spatial resolution cardiac MRI at 7.0T.
• The array is compatible with multichannel transmission, paving the way for parallel transmission techniques.
• This technology provides a foundation for future clinical assessments of advanced MRI methods at 7.0T.