1. Field of the Invention
The invention relates to an MR method for the image-assisted monitoring of the displacement of an object relative to a vascular system, in which a first MR data set is acquired which represents the course of the vascular system within a three-dimensional volume, after which the position of the object is continuously measured and reproduced in an MR angiogram derived from the first MR data set.
2. Description of Related Art
An MR method of this kind is known from Proceedings of 3rd SMR, 490, 1995. A comparatively long period of time (from 8 to 20 minutes) is required for the acquisition of an MR data set. Therefore, this MR data set is acquired before introduction of the object, for example a catheter, into the vascular system. After introduction of the catheter, the position of the object is continuously measured in real time and is reproduced in an MR angiogram derived from the first MR data set.
The known method meets its limits when the patient moves during the intervention. The real-time measured position of the object can then no longer be reproduced at the correct location in the angiogram, because the motion of the patient has not been taken up in the angiogram.