Abstract: A method for navigation assistance in a medical procedures, the method may include (i) obtaining evaluated images that capture the OOI and the background; wherein the evaluated images are acquired at other points of time during which the one or more injection agents do not flow through at the least one of the BVSs; (ii) determining evaluated image features of the evaluated images by the machine learning process trained to extract the features; (iii) generating predicted BVSs maps for the evaluated images, based on the reference BVSs map information; and (iv) responding to the generating of the predicted BVSs maps and the dynamic movement of the OOI.