Advances in Flexible AIR™ Coil Technology for Neuro, Body, MSK, Breast and MNS Applications

Since the advent of the MRI phased array there has been a continual evolution of the technology with increasing element density and accommodation for parallel imaging. In more recent years there has been a move towards the development of ultra-flexible coil technology which affords more conformality to the human form and detection elements closer to the body. To accommodate such flexible technology some critical advances in electronic miniaturization, cable management and element-to-element immunity has had to be tackled. Examples of highly decoupled elements have been shown in the literature [1] [2] [3] . This has led to the exploration of possible wearable coils for a variety of body regions and we examine here some of those have been prototyped using AIR™ Coil technology [4] [5] [6] [7] . At the same time multi-nuclear arrays are also being developing with high channel count, which have the same need for patient conformality and higher SNR [8] . In this work we explore the expanding interest in flexible array technology for applications with both 1H and 13C nuclei and provide examples that have built, tested and evaluated. Specifically, novel wearable receive coils were constructed on fabric including (a) Head / Neck (b) Pelvis, (c) Bilateral brachial plexus, (d) Breast, and (e) a large body sized 13C receive blanket. The coils were designed to accommodate the 5th percentile woman up to the 99th percentile male. The flexible neck, pelvic, brachial plexus arrays were made using a highly flexible 1mm conductor construction. A 32.1MHz 16Ch array was made for 13C body imaging made using a conductor construction of 2.3mm diameter. Pre-amplification, decoupling and matching circuitry is included in a discrete module connected to the Air™ loop conductor. No loss in coil sensitivity relative to conventional 2oz copper PCB technology was found.