What is a key characteristic of surface coils in MRI?

A key characteristic of surface coils in MRI is that they are designed to be positioned close to the area of interest in order to provide high-quality images with improved signal-to-noise ratios. When surface coils are oriented correctly, often aligned with the anatomy being scanned, they optimize the magnetic field sensitivity, which is crucial for capturing detailed images of superficial structures.

The proper positioning in relation to the XY plane is essential since it maximizes the coil's efficiency in detecting the signals emitted from the tissues within the imaging volume. This alignment ensures that the coil receives the strongest possible signals from nearby tissues and minimizes noise from surrounding areas, contributing to clearer images.

While other aspects such as the transmission of signals, multiple receiver channels, and quadrature operation contribute to the functionality of various coils in MRI, the orientation and positioning of surface coils stand out as critical for achieving high-quality imaging results.