Patient alignment system for NMR studies

A patient alignment system useful with an NMR system for acquiring NMR data in the course of a scan of a predetermined volume of a patient, the NMR system including a magnet for producing a polarizing magnetic field within a magnet bore sized for receiving the patient volume, and a patient transport system in general longitudinal alignment with the magnet bore capable of positioning the patient volume for scanning in an advanced position in the active region of the magnetic field centered approximately at the isocenter and for retrieving the patient volume to a staged position substantially out of the active region of the magnetic field, the patient alignment system comprising:

• a first assembly including at least one energy source capable of projecting in use a first visible pattern on the surface of a patient;
• first means for detecting the position of the patient transport system when said first visible pattern is aligned with a patient anatomical reference point in the staged position prior to performing the NMR scan;
• a second assembly including at least one energy source means capable of projecting in use a second visible pattern lying substantially in a horizontal plane on a surface of a patient, said second assembly including means for varying in use within a predetermined range the vertical position relative to the horizontal plane of said second visible pattern with respect to a fixed reference point;
• second means for detecting the position of said second visible pattern on the patient surface;
• and
• control means in signal communication with said first and second means for detecting, said control means being responsive to the position of at least one of the first and second visible patterns for controlling at least one parameter used for altering at least one of NMR data acquisition, image reconstruction and display.