The Directory shall include Directory Records of PATIENT, STUDY, SERIES, IMAGE corresponding to the information object files in the File Set. All DICOM files in the File Set incorporating SOP Instances (Information Objects) defined for the specific Application Profile shall be referenced by Directory Records. At the image level each file contains a single ultrasound image object or a single ultrasound multi-frame image object as defined in PS 3.3 of the standard.
NOTE: For all media selected in this Application Profile Class, STD-US, the following applies as defined in PS 3.12.
All implementations should include the DICOM Media Storage Directory in the DICOMDIR file. There should only be one DICOMDIR file on a single media. The DICOMDIR file should be found in the root directory of the media. For the case of double-sided MOD media, there shall be a DICOMDIR on each side of the media.
On a single media the patient ID key at the patient level shall be unique for each patient directory record.
File Set Creators and Updaters are only required to generate mandatory elements specified in PS 3.10. At each directory record level any additional data elements can be added as keys, but is not required by File Set Readers to be able to use them as keys.
Note: File Component IDs should be created using a random number filename to minimize File Component ID collisions as described in PS 3.12. The FS-Updater should check the existence of a Component ID prior to creating that ID. Should an ID collision occur, the FS-Updater should try another ID.