A method for determining a distance between a first point and a second point on an object under examination inside the body of a person under examination by way of x-ray imaging by an x-ray device. The method includes the recording of x-ray images at different relative positionings of the x-ray device, which contain the first and the second point respectively. The relative positionings are substantially shifted in relation to one another in parallel to a central beam. Stereo reconstruction is carried out to define a 3D position of the first point and of the second point. The distance between the first point and the second point is determined from the 3D position of the first point and the 3D position of the second point.