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  1. If a collection of images are is produced by equipment from different manufacturers, collisions may occur in the sets of private elements to be retained and discarded. For example, element (0009, 1001) from manufacturer A may contain an important physical parameter while that same element from manufacturer B may contain PHI.

  2. If the collection has images created by an acquisition modality and then modified by another application (PACS, workstation), a private group may have multiple reserved blocks. Also, one cannot assume that the original creator will always choose reserved block 0010.


These outputs are relevant at different stages of the curation and image publication process:

  • Element Inventory: The element inventory consists of a set of DICOM tags found in the image set; .  The DICOM tags include only hexadecimal tags (xxxx, yyyy) and no values. All public and private tags are listed once. The Confidentiality Profile and Modality Software Profile are not consulted, as no values are retained for review.
  • Element Values Before De-identification: Element values are examined to determine how to configure CTP scripts for proper de-identification. As mentioned above, we want to retain as many elements as possible while not exposing PHI. We also do not want to review all element values in all DICOM objects. We use a Confidentiality Profile that corresponds to the DICOM Basic Application Confidentiality Profile and a Modality Software Profile that properly describes private elements in DICOM objects.
  • Element Values, Final Review: To review the values in DICOM objects after data is de-identified, as a final check before publication, this mode uses a different Confidentiality Profile and a different Modality Software Profile. For the Confidentiality Profile, we only list elements that are known physical parameters (rows, columns, etc.) and do not include the DICOM references from PS 3.15, Table E.1-1. That directs the software to record the element values. Likewise, the Modality Software Profile directs the software to record all values for later analysis.