What type of surface coils are used with permanent magnets that have a vertical magnetic field?

Surface coils used with permanent magnets that have a vertical magnetic field typically include solenoids. Solenoids are designed to provide a uniform magnetic field and are effective for imaging at depths due to their geometric configuration. When used with permanent magnets, which naturally create a vertical magnetic field, solenoids can take advantage of the orientation and provide optimal signal-to-noise ratios for imaging the body.

In a solenoid coil, the magnetic field generated is concentrated within its center, making it particularly suitable for imaging areas directly beneath the coil. This design allows for a more focused detection of the signals emitted from the scanned tissue when the magnetic field is aligned vertically, which is the typical configuration of permanent magnets.

Other types of coils, such as phased array and linear coils, might also be used but can have different applications and may not perform as effectively with permanent magnets that operate with a vertical field. Specifically, phased array coils provide multi-channel capabilities for imaging larger areas or more complex structures but may not be as effective in signal detection as solenoids in this context. Quadrature coils are designed for specific frequency applications and may not be as optimal for permanent magnet systems when compared to solenoids.

Thus, solenoids are the preferred choice for surface coils in