SYSTEME ET PROCEDE D'ACQUISITION D'IMAGE ANGIOGRAPHIQUE AVEC ADAPTATION AUTOMATIQUE DE L'OBTURATEUR PERMETTANT D'OBTENIR UN CHAMP D'OBSERVATION REDUIT COUVRANT UNE LESION OU STRUCTURE CIBLE SEGMENTEE AFIN DE REDUIRE LA DOSE DE RAYONS X DANS LE CADRE D'INTERVENTIONS MINI-INVASIVES GUIDEES PAR RAYONS X
The present invention refers to an angiographic image acquisition system and method which can beneficially be used in the scope of minimally invasive image-guided interventions. In particular, the present invention relates to a system and method for graphically visualizing a pre-interventionally virtual 3D representation of a patient's coronary artery tree's vessel segments in a region of interest of a patient's cardiovascular system to be three-dimensionally reconstructed. Optionally, this 3D representation can then be fused with an intraoperatively acquired fluoroscopic 2D live image of an interventional tool. According to the present invention, said method comprises the steps of subjecting the image data set of the 3D representation associated with the precalculated optimal viewing angle to a 3D segmentation algorithm (S4) in order to find the contours of a target structure or lesion to be examined and interventionally treated within a region of interest and automatically adjusting (S5) a collimator wedge position and/or aperture of a shutter mechanism used for collimating an X-ray beam emitted by an X-ray source of a C-arm-based 3D rotational angiography device or rotational gantry-based CT imaging system to which the patient is exposed during an image-guided radiographic examination procedure based on data obtained as a result of said segmentation which indicate the contour and size of said target structure or lesion. The aim is to reduce the region of interest to a field of view that covers said target structure or lesion together with a user-definable portion of the surrounding vasculature.