As the coils have to be placed directly onto the patient table of an MR system, their high RF power supply cables are thus close to a patient. The use of dedicated transceive coils for extremities at the clinical MR systems has been proven useful to investigate fine details, e.g., of joint anatomies 5. At the same time, the presence of fragile elements demands careful handling each time these coils are positioned and dismounted before and after every MR examination (Fig. In addition, the RF coils are usually relatively heavy and bulky. Because of that reason, cable traps and matching circuits are included in receive coils designs to increase patient safety and signal-to-noise ratio 4. Furthermore, in the case of receive-only coils, common-mode currents are induced in RF cables by the body coil. The RF magnetic field of the body birdcage coil is distributed over its total volume, requiring higher power during excitation 3 that limits the coil transmit efficiency for small areas. Such investigations, in principle, demand excitation and reception of MR signal only from the volume of interest. These limitations are exceptionally prominent for a modern trend of highly specialized clinical MR investigations with a relatively small (compared to average body size) target (e.g., the head, spine, joint, breast) 2. This combination provides acceptable image quality of MR examinations of the whole body as well as body parts or organs but has some limitations in the current state-of-the-art. The conventional concept of excitation and reception of the electromagnetic signal at clinical MR systems (i.e., 1.5–3 Tesla) includes a large, human-sized transmit radiofrequency (RF) volume body birdcage coil and receive-only surface coil (Fig. Naturally, the amount of clinical applications of MRI is increasing, and with it, the number of targeted MR examinations of a particular body part or organ, e.g., the liver. As magnetic resonance imaging (MRI) provides outstanding quality and richness of the visualized information in combination with non-invasiveness and safety, MRI has gained significant medical use, and the amount of installed clinical magnetic resonance (MR) scanners in the world continues to grow 1.
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