Theoretical signal-to-noise ratio of a slotted surface coil for magnetic   resonance imaging
  The analytical expression for the signal-to-noise ratio of a slotted surface coil with an arbitrary number of slots was derived using the quasi-static approach. This surface coil based on the vane-type magnetron tube. To study the coil perfomance, the theoretical signal-to-noise ratio predictions of this coil design were computed using a different number of slots. Results were also compared with theoretical results obtained for a circular coil with similar dimensions. It can be appreciated that slotted surface coil performance improves as the number of coils increases and, outperformed the circular-shaped coil. This makes it a good candidate for other MRI applications involving coil array techniques. 
K. Ocegueda, S. S. Hidalgo, S. E. Solis, A. O. Rodriguez
physics.med-ph physics.ins-det