The present invention relates to a system and a method for monitoring/tracking the movement of an object in a location which is difficult to access, such as the movement of a patient in a clinical MRI scanner. This is achieved by an optical motion tracking system for determining the movement of an object at least partly located in a volume of difficult access and/or at least partly located in an electromagnetic field, said system comprising a borescope for imaging a pattern on the object or a surface part of the object with a camera, said pattern or surface part located adjacent to a distal end of the borescope and said camera attached to a proximal end of said borescope, and image processing means for calculating the movement of said pattern or surface part relative to the distal end of the borescope based on a plurality of frames/images captured by the camera. The invention further relates to the use of a borescope for motion tracking of an object and a marker plate suitable for use in the motion tracking system.
