C.8.8.15.14 Orientation of Brachy Sources

The Control Point Orientation (300A,0412) shall be used to define the orientation of an anisotropic brachytherapy source or seed for the purpose of calculating the effect of the anisotropy on the dose calculation. The Control Point Orientation (300A,0412) shall be given by the direction vector of the long axis of the Brachy source or seed in the insertion direction, in the DICOM Patient Coordinate System. The direction vector shall be oriented from the source center as defined by the Control Point 3D Position (300A,02D4) along the long axis of the source and in the insertion direction.