Method and apparatus for visualization of tissue perfusion by means of assessing BOLD signal fluctuations

The invention relates to method, an apparatus and the use thereof of visualization of areas of the tissue insufficiently supplied with blood, in particular in the event of an acute stroke, by evaluation of local fluctuations of a BOLD signal comprising the following steps: - producing and recording of BOLD signal data by means of an apparatus (8); - passing on the BOLD signal data to a data detection device (10) by way of at least one interface; - sending the BOLD signal data received from the data detection device (10) to an evaluation device; - pre-processing BOLD in a first evaluation device (12) for image recognition; - applying a time delay analysis to the BOLD signal data of at least one voxel in a second evaluation device (14) in order to calculate a time dependent positive and negative phase shift (I1, 12) of the BOLD signal data of at least one voxel, and - assigning a reference value which reference value is an estimated time delay between the BOLD signal data of at least one voxel and the entire average time course of a selected region during the recording of the BOLD data in order to estimate a modified BOLD signal data which are used to determine at least one area of the hypoperfused tissue.