Method for a positioning control of an object under investigation before acquiring a projective x-ray image

A computer-implemented method to create a set of reference object models for at least one examination pose and at least one region of interest, the computer-implemented method comprising:

• providing a plurality of different object models including at least one landmark for a corresponding region of interest;
• adapting the plurality of different object models to the at least one examination pose to generate reference object models;
• generating, for each reference object model, a forward projection of the at least one landmark comprised by the reference object model in an X-ray geometry relating to the examination pose and the region of interest;
• providing the plurality of different object models in a standard examination pose;
• generating a forward projection of the at least one landmark comprised by an object model in the standard examination pose in the X-ray geometry relating to the examination pose and the region of interest;
• and
• determining a positioning deviation by comparing the forward projection of the reference object model to a forward projection of a corresponding object model in the standard examination pose.

A medical X-ray system comprising:

• a first interface configured to receive object information of an object under investigation in an examination pose;
• a second interface configured to retrieve an object model relating to the examination pose and a region of interest;
• a third interface configured to adapt the object model to the object under investigation based on the object information;
• and
• a fourth interface configured to evaluate the examination pose based on the adapted object model.