For RDSR consumers it is useful to distinguish between several X-Ray modes applied during the Irradiation Event (e.g., Fluoroscopy or Acquisition). Both Traditional and Enhanced RDSR include a Content Item that is a basic classification of X-Ray modes used as a condition for the presence of other Content Items.

The Content Item (113721, DCM, "Irradiation Event Type") in TID 10003 “Irradiation Event X-Ray Data” and in TID 10042 “Irradiation Event Summary Data” is mandatory in both traditional RDSR and enhanced RDSR. It distinguishes between X-Ray modes that distinct types of equipment can apply.

Table UUUU.4.10-1 describes the CID 10002 “Irradiation Event Type”and their applicability to the different modalities.

In the Traditional RDSR for X-Ray Projection, when the X-Ray source moves angularly on a free trajectory (i.e., not necessarily following a planar rotation around an axis), the Irradiation Event Type should be (113613, DCM, "Rotational Acquisition"), regardless of whether or not the X-Ray source moves laterally in relation to the patient. This satisfies the condition for the presence of the Content Items (113739, DCM, "Positioner Primary End Angle") and (113740, DCM, "Positioner Secondary End Angle") in TID 10003C “Irradiation Event X-Ray Mechanical Data” that otherwise are prohibited. In the Enhanced RDSR, the position of the X-Ray Source can be encoded at any period of time during the movement, which allows full description of the X-Ray source trajectory.

In the Traditional RDSR for CT the Content Item (113721, DCM, "Irradiation Event Type") is not defined. In the Enhanced RDSR, the Content Item (113721, DCM, "Irradiation Event Type") in TID 10042 “Irradiation Event Summary Data” can be used in CT equipment to document a Rotational Acquisition, and then use the optional item (113820, DCM, "CT Acquisition Type") in the same TID 10042 to specify the details of the CT rotation as defined in the CID 10013 “CT Acquisition Type” (e.g., spiral, sequenced, constant angle, free, cone beam).