How does a linear coil differ from a quadrature coil?

A linear coil is designed to receive signals from only one component of the magnetization, specifically either the in-phase or the quadrature phase, but not both simultaneously. This limitation means that linear coils can be less efficient in capturing the full range of signal information available in MRI, as they effectively sample only half of the available data from the rotating magnetization vector.

In contrast, a quadrature coil utilizes two coils that are tuned to detect both components of the magnetization—the in-phase and the quadrature phase. This approach significantly enhances the sensitivity and efficiency of signal detection, allowing for improved image quality and reduced acquisition times.

Understanding the characteristics of these coils is crucial for optimizing MRI techniques. The choice of coil affects the quality of the images produced and impacts the diagnostic outcomes, highlighting why the design and operational principles of the coils matter so significantly in different MRI applications.