Vorrichtung und Verfahren zur magnetischen Induktionstomographie

A method and an apparatus for magnetic induction tomography, where an object having inhomogeneous electrical properties is subjected to alternating magnetic fields by means of at least one transmitter coil (ES1, ES2, ES3), picking up alternating voltage signals which contain information on the electrical conductivity and its distribution in the object by means of at least one receiving coil (SP1, SP2, SP3), and reconstructing an image of the electrical properties within the object from the received signals, having an imaginary and a real part, by using their different phases and amplitudes, whereby a set of markers (MAR) is placed on the surface of the object under investigation, the markers being selected from the group of markers producing a signal which is clearly distinguishable from that of the object, measurements are performed to reconstruct the image of the object itself on the one hand and reconstructing the image and location of the markers (MAR) on the other hand and filtering out the movements of the outer object boundary in order to eliminate artifacts due to such movements. Each marker (MAR) may be an active marker consisting of a loop (LOO), the wire being electrically conducting, and a remotely controlled switch (SWI), adapted to open and close the loop.