Abstract: Various methods and systems are provided for a medical imaging system. In one embodiment, a method for a projection imaging system includes acquiring a first image of a region of interest (ROI) with the projection imaging system in a first position, determining a three-dimensional (3D) location of an annotation on the first image via a geometric transformation using planes, acquiring a second image of the ROI with the projection imaging system in a second position, determining a location of the annotation on the second image based on the 3D location of the annotation in the first position and a geometry of the second position, and displaying the annotation on the second image in response to an accuracy check being satisfied.