A computer-implemented method for reconstructing a three-dimensional representation of a target volume inside an animal or human body, said method comprising the steps of: i) acquiring a first two-dimensional image projection of said target volume using imaging means being positioned in a first imaging position, ii) acquiring a second two-dimensional image projection (25") of said target volume using said imaging means being positioned in a second imaging position, iii) reconstructing from said two-dimensional image projections (25', 25") a three-dimensional contour image of said target volume using transformation means, iv) displaying said three-dimensional contour image of said target volume for a user using displaying means, wherein step ii) is preceded by the additional steps of: a1) displaying said first two-dimensional image projection being obtained in step i) for a user using said displaying means, a2) acquiring a first operational orientation setting (α1, β1) of said imaging means corresponding with said first imaging position; a3) defining based on said first operational orientation setting (α 1, β 1) a first set of second operational orientation settings of said imaging means for orientations in the second imaging position; a4) determining a longitudinal orientation of said target volume in said first two-dimensional image projection; selecting from said set one (α 2, β 2) of said second operational orientation settings such that the selected second operational orientation settings (α 1, β 1) corresponds to a second imaging position being defined in a plane perpendicular to said longitudinal orientation of said target volume; a5) using said second operational orientation setting (α 2, β 2) being selected for acquiring said second two-dimensional image projection (25") of said target volume using said imaging means being positioned in the second imaging position corresponding to said second operational orientation setting (α 2, β 2). i) acquiring a first two-dimensional image projection of said target volume using imaging means being positioned in a first imaging position, ii) acquiring a second two-dimensional image projection (25") of said target volume using said imaging means being positioned in a second imaging position, iii) reconstructing from said two-dimensional image projections (25', 25") a three-dimensional contour image of said target volume using transformation means, iv) displaying said three-dimensional contour image of said target volume for a user using displaying means, wherein step ii) is preceded by the additional steps of: a1) displaying said first two-dimensional image projection being obtained in step i) for a user using said displaying means, a2) acquiring a first operational orientation setting (α1, β1) of said imaging means corresponding with said first imaging position; a3) defining based on said first operational orientation setting (α 1, β 1) a first set of second operational orientation settings of said imaging means for orientations in the second imaging position; a4) determining a longitudinal orientation of said target volume in said first two-dimensional image projection; selecting from said set one (α 2, β 2) of said second operational orientation settings such that the selected second operational orientation settings (α 1, β 1) corresponds to a second imaging position being defined in a plane perpendicular to said longitudinal orientation of said target volume; a5) using said second operational orientation setting (α 2, β 2) being selected for acquiring said second two-dimensional image projection (25") of said target volume using said imaging means being positioned in the second imaging position corresponding to said second operational orientation setting (α 2, β 2). a1) displaying said first two-dimensional image projection being obtained in step i) for a user using said displaying means, a2) acquiring a first operational orientation setting (α1, β1) of said imaging means corresponding with said first imaging position; a3) defining based on said first operational orientation setting (α 1, β 1) a first set of second operational orientation settings of said imaging means for orientations in the second imaging position; a4) determining a longitudinal orientation of said target volume in said first two-dimensional image projection; selecting from said set one (α 2, β 2) of said second operational orientation settings such that the selected second operational orientation settings (α 1, β 1) corresponds to a second imaging position being defined in a plane perpendicular to said longitudinal orientation of said target volume; a5) using said second operational orientation setting (α 2, β 2) being selected for acquiring said second two-dimensional image projection (25") of said target volume using said imaging means being positioned in the second imaging position corresponding to said second operational orientation setting (α 2, β 2).