The present invention relates, in general, to the field of motion
tracking, and in particular to join a target in an MRI application. In
particular the invention teaches an apparatus and method to track the
movement of a target during medical imaging scanning using optical
technology. Optical systems record the position and movement of the
pattern and are able to perform mathematical analysis of the pattern to
determine the positional shift of the patient. Weighted averages, Fourier
transforms, Hadamard matrices and cross-correlation of data related to
X-Y translation, rotation and scaling of the image of the pattern are
used to analyze movement of the subject's head. Feedback related to the
movement is provided to the MRI machine which allows for adjustments in
focusing coils for real time tracking of the patient's movements during
the MRI procedure. As a result, the MRI procedure becomes more accurate
as it is adjusted for the patient's movements.