Coil sensitivity estimation for parallel imaging

An MRI apparatus that includes a magnet system for generating a B0 magnetic field in an examination zone, the apparatus comprising:

• means for exciting and manipulating magnetic resonance in the examination zone;
• means for spatially encoding the magnetic resonance;
• plurality of coils with differing sensitivity profiles for receiving resonance signals in parallel;
• means for reconstructing received resonance signals into image representations;
• means for generating sensitivity profiles of the coils from image representations generated during a calibration scan;
• means generating a diagnostic image from the sensitivity profiles and image representations generated during a diagnostic scan;
• sequence control means for accessing a calibration sequence memory means to retrieve one of an RF refocused spin echo type sequence and a gradient recalled echo type sequence and controlling the resonance exciting means and the spatial encoding means in accordance with the retrieved calibration sequence to generate resonance signals for the reconstruction means to reconstruct into the calibration image representations and for accessing a diagnostic imaging sequence memory means to retrieve a diagnostic imaging sequence and controlling the resonance exciting means and the spatial encoding means to generate resonance signals for the reconstruction means to reconstruct into the diagnostic image representations.