What type of coils can transmit and receive signals in MRI?

The correct choice refers to volume coils, which are designed to both transmit radiofrequency (RF) energy and receive signals from the tissues being imaged in an MRI. These coils generally encompass a larger area and are capable of capturing signals from a broader volume of tissue, making them effective for imaging larger anatomical structures.

Volume coils work by creating a uniform magnetic field necessary for producing high-quality images. They are typically constructed as solenoids or birdcage designs that ensure an even distribution of the RF field, which is vital for accurate imaging. Their ability to effectively transmit and receive signals makes them a foundational component in MRI technology.

In contrast, surface coils are primarily designed for receiving signals; they are placed near the surface of the body and are highly sensitive to the signals from tissues close to them but are less effective for deeper imaging. Phased array coils consist of multiple smaller coils that work together, and while they can also transmit and receive signals, they do so in a way that optimizes resolution and sensitivity over a specific area rather than the broader volume coverage expected from volume coils. Gradient coils, on the other hand, play a different role in MRI by creating varying magnetic field gradients necessary for spatial encoding of the MRI signal rather than for signal transmission or