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The Cancer Imaging Archive (TCIA) staff has accumulated a wealth of knowledge on best practices and procedures for DICOM image de-identification in the process of maintaining our archive. In order to share this information with the wider research community we are maintaining the following knowledge base. This is a living document and will continue to be updated as we learn from our experiences. If you have feedback or questions please contact us at feedback@cancerimagingarchive.net.

Background Information

Here are some presentations and papers which provide an overview on various aspects of DICOM de-identification and the official Supplement 142 de-identification standards:

  1. Image Data Sharing for Biomedical Research: Meeting the De-identification and Informatics Challenges publication, Journal of Digital Imaging (DOI: 10.1007/s10278-011-9422-x)
  2. Image Data Sharing for Biomedical Research: Meeting the De-identification and Informatics Challenges presentation, SIIM Annual Meeting, Washington, D.C., June 4, 2011
  3. De-identification Revisited - DICOM Supplement 142 presentation, DICOM Conference 2010
  4. Automated Standards-based Anonymization Profile for Image Sharing Using RSNA's Clinical Trial Processor poster with Q&A session, RSNA Annual Meeting, Chicago, IL, Nov 30, 2009

DICOM Private Data Elements

It is desirable to retain DICOM private data elements that contain parameters describing the acquisition while removing elements containing PHI. Performing this task requires understanding the mechanism defined by DICOM to support private elements. DICOM PS 3.5, section 7.8.1 states:

It is possible that multiple implementors may define Private Elements with the same (odd) group number. To avoid conflicts, Private Elements shall be assigned Private Data Element Tags according to the following rules.

a)     Private Creator Data Elements numbered (gggg,0010-00FF) (gggg is odd) shall be used to reserve a block of Elements with Group Number gggg for use by an individual implementor. The implementor shall insert an identification code in the first unused (unassigned) Element in this series to reserve a block of Private Elements. The VR of the private identification code shall be LO (Long String) and the VM shall be equal to 1.

b)    Private Creator Data Element (gggg,0010), is a Type 1 Data Element that identifies the implementor reserving element (gggg,1000-10FF), Private Creator Data Element (gggg,0011) identifies the implementor reserving elements (gggg,1100-11FF), and so on, until Private Creator Data Element (gggg,00FF) identifies the implementor reserving elements (gggg,FF00-FFFF).

c)     Encoders of Private Data Elements shall be able to dynamically assign private data to any available (unreserved) block(s) within the Private group, and specify this assignment through the blocks corresponding Private Creator Data Element(s). Decoders of Private Data shall be able to accept reserved blocks with a given Private Creator identification code at any position within the Private group specified by the blocks corresponding Private Creator Data Element.

We will use data in group 0009 as a practical example. The table below shows an example of data that could be included in group 0009.

Tag

Description

Value

0009, 0010

Private Creator  Element

ACME

0009, 1001

Average Density

15.5

0009, 1002

Density Standard Deviation

2.2

In the example, the element with tag (0009, 0010) is a private creator element with value "ACME". That reserves a block of elements for this manufacturer. The element (0009, 1001) is part of that block; the 10 in the element tag (1001) corresponds to the 10 that is in the tag of the Private Creator Element (0009, 0010).

This only becomes complex when different manufacturers want to use the same reserved block to store information. When this occurs in a single image, the creator of the image reserves a block (for example, 0010). When a second application wants to add data to that same group, it detects the block written by the creator and creates a separate block (for example, 0011). The creator is not required to start at block 0010, but that appears to be common practice. The second or third application is not required to use 0011 or 0012. Based on this encoding scheme, some observations are:

  1. If a collection of images are produced by equipment from different manufacturers, you may have collisions in the sets of private elements you want to retain and discard. 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 that are created by an acquisition modality and are then modified by another application (PACS, workstation), a private group may have multiple reserved blocks. Also, one cannot assume that the original creator will have always chosen reserved block 0010.

DICOM Basic Attribute Confidentiality Profile

DICOM standards committee Working Group 18 wrote Supplement 142 that is now incorporated into the published DICOM Standard. The Attribute Confidentiality Profile (DICOM PS 3.15: Appendix E) provides a standard for image de-identification and a process with which to reduce the complexity involved in safely de‐identifying DICOM image data while providing flexibility for scenarios which necessitate preservation of certain information needed for quality control and analysis that is essential to research. This is achieved by providing a number of Application Level Confidentiality Profiles which includes a Basic Profile along with a number of Option Profiles. These profiles provide the necessary instructions for how to safely clean DICOM elements which may contain PHI. The DICOM Standard, including Part 15, is available at the NEMA web site: http://medical.nema.org/standard.html The original Supplement 142 guidance document can be obtained at ftp://medical.nema.org/medical/dicom/final/sup142_ft.doc. We recommend you use the published standard above as it will be updated with any change proposals.

Appendix E of PS 3.15 documents a system for protecting attributes. We quote a small section of the document.

The Attributes listed in Table E.1-1 for each profile are contained in Standard IODs, or may be contained in Standard Extended IODs. An implementation claiming conformance to an Application Level

Confidentiality Profile as a de-identifier shall protect or retain all instances of the Attributes listed in Table E.1-1, whether contained in the main dataset or embedded in an Item of a Sequence of Items. The following action codes are used in the table:

– D – replace with a non-zero length value that may be a dummy value and consistent with the VR

– Z – replace with a zero length value, or a non-zero length value that may be a dummy value and consistent with the VR

– X – remove

– K – keep (unchanged for non-sequence attributes, cleaned for sequences)

– C – clean, that is replace with values of similar meaning known not to contain identifying information and consistent with the VR

– U – replace with a non-zero length UID that is internally consistent within a set of Instances

– Z/D – Z unless D is required to maintain IOD conformance (Type 2 versus Type 1)

– X/Z – X unless Z is required to maintain IOD conformance (Type 3 versus Type 2)

– X/D – X unless D is required to maintain IOD conformance (Type 3 versus Type 1)

– X/Z/D – X unless Z or D is required to maintain IOD conformance (Type 3 versus Type 2 versus Type 1)

– X/Z/U* - X unless Z or replacement of contained instance UIDs (U) is required to maintain IOD conformance (Type 3 versus Type 2 versus Type 1 sequences containing UID references)

PS 3.15: E.2 then defines the Basic Application Level Confidentiality Profile which describes how to apply the scheme above with a number of options that determine the scope of protection that is provided. These definitions allow a system to follow a standard procedure and document in a standard way the behavior of that system.

Software Tools

CTP

TCIA utilizes the RSNA Clinical Trials Processor (CTP) software in conjunction with caBIG's National Biomedical Imaging Archive (NBIA) to de‐identify and host the images in the archive. The Cancer Imaging Program's Informatics Team has been working closely with the developer of CTP since 2009 to incorporate support for this standard as it was being defined by WG18. A full summary and time line of this project can be found athttps://wiki.nci.nih.gov/display/CIP/Incorporation+of+DICOM+WG18+Supplement+142+into+CTP.

CTP provides an interface that allows application of any combination of the profiles to a set of images, and allows for application of an audit trail for retroactively tracking applied de‐identification. For images that are submitted to TCIA the staff begins with the Basic Application Confidentiality Profile (which is the most aggressive) in combination with the following options:

  • Clean Descriptors Option: Removal of identification information from descriptive tags which contain unstructured plain text values over which an operator has control
  • Retain Modified Longitudinal Temporal Information Options: Modification of tags that contain dates or times
  • Retain Patient Characteristics Option: Retention of physical characteristics of the patient that are descriptive rather than identifying information (e.g. metabolic measures, body weight, etc.)
  • Retain Device Identity Option: Retention of information about the characteristics of the device used to perform the acquisition
  • Retain Safe Private Option: Retention of Private Attributes confirmed not to contain PHI

DICOM Tag Sniffer

In order to simplify our ability to implement some of the "clean" instructions specified in DICOM PS 3.15 a new tool was developed to help inspect the contents of DICOM elements which allow free text entry by a technician and Private Tags for potential PHI. This tool scans a folder and included subfolders for DICOM objects and produces several different outputs that depend on the mode used and input profiles. The software reads each DICOM object and iterates through each public and private element. The software then uses the profiles below to determine whether to retain the value of the element for later inspection:

  • Confidentiality Profile: One input profile corresponds to the entries in table E.1-1 in DICOM PS 3.15. We list the attributes in the table and the coded values according to the table entries.  When scanning the DICOM objects, each public element is checked against the data in the profile. If the element is found in the profile, the software knows if it should record the element value for later inspection or if the software can ignore it. For example, if the DICOM profile indicates the element is to be deleted, there is no reason to review the value in that element.
  • The Confidentiality Profile input is augmented with elements that are known to contain physical parameters such as rows, columns or pixel spacing. Rather than tell the software to ignore values with a specific value representation, we list those elements explicitly.
  • Modality Software Profile: This input profile describes the private elements that are documented in the conformance statement by the manufacturer. This file takes into account the Private Creator Data Elements described above and has a code table for indicating program actions (record the value, ignore the value, ...)

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

  • Element Inventory: is the set of DICOM tags that are found in the image set. The tags include only the hexadecimal tags (xxxx, yyyy) and no values. All public and private tags are listed, but each is listed only once. The Confidentiality Profile and Modality Software Profile are not consulted as no values are retained for review.
  • Element Values, Pre-Deidentification: We want to examine element values 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 the private elements in the DICOM objects.
  • Element Values, Final Review: In this mode, we want to review the values in the DICOM objects just before publication. We have de-identified the data and want to analyze the data as a final check. In this mode, we use a different Confidentiality Profile and different Modality Software Profile. For the Confidentiality Profile, we only list elements that we know are physical parameters (rows, columns, ....) and do not include the DICOM references from PS 3.15, Table E.1-1. That will direct the software to record the element values. Likewise, the Modality Software Profile used will direct the software to record all values for later analysis.

We believe this tool might be useful to the rest of the research community and so it's been made freely available as an open source application. We have also created documentation for how a researcher could utilize in the context of their own projects.

TCIA De-identification Work Flow

Image Removed

The TCIA provides standards‐based curation support to ensure safe and thorough de‐identification of all images in the archive per federal HIPAA and HITECH regulations. In order to achieve this compliance without stripping the data of its scientific utility TCIA staff perform a redundant, thorough de‐identification and analysis procedure based on guidance provided by the industry experts in DICOM standards committee Working Group 18. Each collection submitted for publication is analyzed and de-identified as a whole using the steps listed below. All steps are completed before the collection is released for publication.

  1. Each image in the collection is visually inspected to guarantee there is no PHI burned into the pixel data.
  2. TagSniffer is used to review the collection and produce an Element Inventory that is annotated with data from the DICOM Basic Application Confidentiality Profile and our set of Modality Software Profiles. This produces the list of DICOM elements found in the collection with a simple annotation scheme:
    1. One of the Basic Application Confidentiality Profile codes that indicates the DICOM scheme for de-identification (if the element is listed by DICOM)
    2. A simple code from our Modality Software Profile (No PHI: Retain, PHI: Delete, Not Sure: Review)
    3. No code, indicating the element is not registered
  3. The Pre-Identification output of the Tag Sniffer is also generated. This will contain the set of elements in the collection and all values that need to be reviewed for PHI. If the Basic Application Confidentiality Profile or applicable Modality Software Profile indicates the attribute is to be cleaned or that the attribute is a physical parameter that does not contain PHI, there is no need to review that element at this step. We know that our de-identification script will process the element properly.
  4. We combine the information from steps 2 and 3 to create a CTP de-identification script for the collection. In the event of multiple scanners from different manufacturers, we might create and apply different scripts based on manufacturer.
  5. The CTP de-identification script (or scripts) is (are) applied to the image collection and a separate copy of the images is created. That is, we retain the original set in case we need to repeat a step.
  6. TagSniffer is used to review the de-identified images and create the Final Review Output. This is a more complete output that is reviewed by analysts to guarantee there is no PHI carried forward after de-identification. Both public and private elements are included in the output for review.
  7. If any errors are detected in de-identification in step 6, the CTP script is adjusted and the image set is processed again starting at step 5.

Only after this inspection is complete are the images made available to the general public. For general information on what to expect as an image provider please see our web site at http://www.cancerimagingarchive.net/provider.html.

DICOMRT-Specific Issues

Manufacturer Specific Private Tags

As discussed above, medical manufacturers include private elements in their DICOM images to convey information not defined in the DICOM Standard. This section documents the information we have gathered by reading appropriate conformance statements.

The sections below describe information by manufacturer. That information is encoded in files that describe the private elements created by those manufacturers. Those files are part of the run time environment of the Tag Sniffer and are maintained in our forge: https://mirgforge.wustl.edu/gf/project/dicomtagsniffer/scmsvn/?action=browse&path=%2Ftrunk%2Fdeploy%2Fprofiles%2Fdevice-profiles%2F

GE Medical Systems

GE Discovery CT

GE Signa MR series

Philips

Philips Achieva MR series

Siemens

Overview

Updated: 30 June, 2015

 

Excerpt
Following industry best-practices, TCIA uses a standards-based approach to de-identification of DICOM images to insure that images are free of protected health information (PHI).  The TCIA de-identification process ensures that the HIPAA de-identification standard is met by following the Safe Harbor Method as defined in section 164.514(b)(2) of the HIPPA Privacy Rule. The standard for de-identification of DICOM objects is defined by the DICOM Standard PS 3.15-2011 Digital Imaging and Communications in Medicine (DICOM), Part 15: Security and System Management Profiles (ftp://medical.nema.org/medical/dicom/2016b/output/html/part15.html#chapter_E). At the submitting site, a DICOM PS 3.15 compliant script removes or modifies DICOM tags deemed to be unsafe (See table 1 for a complete listing). TCIA incorporates the “Basic Application Confidentiality Profile” which is amended by inclusion of the following profile options: Clean Pixel Data Option, Clean Descriptors Option, Retain Longitudinal With Modified Dates Option, Retain Patient Characteristics Option, Retain Device Identity Option, and Retain Safe Private Option.  The de-identification rules applied to each object are recorded by TCIA in the DICOM sequence Method Code Sequence [0012,0063] by entering the Code Value, Coding Scheme Designator, and Code Meaning for each profile and option that were applied to the DICOM object during de-identification. The DICOM standard for de-identification of objects defines a minimum set of elements to de-identify to be in compliance with the standard. It is up to the user doing the de-identification to insure that PHI is removed or cleaned according to the laws and practices in place at the time de-identification occurs.

Details

Base level de-identification 

The Basic Application Confidentiality Profile requires that Patient Name and Patient ID are either blanked or modified. TCIA incorporates an ID mapping between the original Patient ID and the ID that the images will have within TCIA.  The mapping table is created at the image submitting site, the mapping performed prior to the images leaving the sites host computer, and TCIA never sees the original Patient ID. The remapped Patient ID is also mapped to the Patient Name field. This is done for the case where a DICOM viewer or application being used by the TCIA user that downloaded the data would require a Patient Name to be present. To show that the Patient Identity has been removed, the term “YES” is written into DICOM tag 00120062 “PatientIdentityRemoved”.

In general, the Basic Application Profile specifies removal or modification of any tag that by definition would contain PHI that could be used either alone or together with other information to uniquely identify a subject. Removal of detailed geographic information, dates, exam identifiers, patient demographics, free text entry fields, vendor private tags, etc. are all done to minimize the possibility of being able to uniquely identify an individual. The options to the DICOM de-identification standard allows for retention of information to help make the data scientifically valuable, but as more options are added the chance of PHI is increased and a rigorous de-identification process must be followed.

Exam Identifiers - DICOM makes extensive use of universal identifiers (UID) that could be used to identify a subject if a user had access to the PACS system at the institution where the images originated. The Basic Application Confidentiality Profile requires that all UIDs be removed or modified.  TCIA uses its own root UID, appends an 8 digit string in the form of xxxx.yyyy (where xxxx is related to the collection and yyyy is related to a submitting site) and then appends a hashed value of the original UID. UIDs have no special meaning other than serving as unique identifiers and the only reason TCIA adds the 8 digit string is to minimize the possibility of two images being assigned the same UID as images come from many different sites. This technique insures that images stay associated with the appropriate series, study, and subject as well as ensuring that referenced images between secondary capture images, structured reports, PET/CT, etc. are still valid references to images within TCIA. Any image resubmitted to TCIA will have the same UID to avoid the same image appearing twice with a different identifier. Original accession numbers are hashed with a 16 bit string to prevent linking of DICOM objects back to the submitting site.

Dates - The Retain Longitudinal With Modified Dates Option allows dates to be retained as long as they are modified from the original date. Date and Date-Time fields in TCIA DICOM image headers have been offset based on a random number, but the longitudinal relationship between dates is maintained.  Therefore, a researcher won’t know the precise date the scan occurred, but if a follow up scan was performed 120 days later, that same 120 day difference between scans of a subject will exist in the TCIA images.  Dates that occur in DICOM tags other than Date or Date-Time fields are removed. An example of this would be a date entered into the Series Description field.  If the date is associated with a library for Code Meaning then that date is preserved as the date would be required to look up the meaning in the correct version of the library.  To show that the dates have been modified, the term “MODIFIED” is written into DICOM tag 00280303 “LongitudinalTemporalInformationModified”.

Patient Demographics – The keep Patient Characteristics Option allows keeping some patient demographics for research purposes. The allowed fields are Patient’s Sex, Patient’s Age, Patient’s Size, Patient’s Weight, Ethnic Group, Smoking Status, and Pregnancy Status. If a subject is over 90 years of age, then the age must be listed as 90+.  Allergies, Patient State (this is not where they live, rather their condition), Pre-Medication, and Special Needs are defined by the DICOM standard as “clean” and are kept by TCIA and examined for PHI along with all tags during curation. Other patient demographics such as birthdate, address, religious affiliations, etc. are removed or emptied.

The names of health care providers including staff, hospital name, assigned IDs etc. are removed from the DICOM objects in cases where there is enough detail to identify an individual or facility where the scan was done.

Free Text - The Clean Descriptors Option allows for DICOM tags where free text could be entered by a technician to be kept. The following tags fall under that option and are all kept, inspected, and cleaned of PHI by TCIA during the curation process: Allergies, Patient State, Study Description, Series Description, Admitting Diagnoses Description, Admitting Diagnoses Code Sequence, Derivation Description, Identifying Comments, Medical Alerts, Occupation, Additional Patient’s History, Patient Comments, Contrast Bolus Agent, Protocol Name, Acquisition Device Processing Description, Acquisition Comments, Acquisition Protocol Description, Contribution Description, Image Comments, Frame Comments, Reason for Study, Requested Procedure Description, Requested Contrast Agent, Study Comments, Discharge Diagnosis Description, Service Episode Description, Visit Comments, Scheduled Procedure Step Description, Performed Procedure Step Description, Comments on Performed Procedure Step, Requested Procedure Comments, Reason for Imaging Service Request, Imaging Service Request Comments, Interpretation Text, Interpretation Diagnosis Description, Impressions, and Results Comments. The TCIA de-identification script run at the submitting sites removes the field “Request Attributes Sequence” as that tag typically contains PHI and provides no scientific value.  Many of these fields contain information valuable to research and are important to retain. For images that are submitted with missing Series Descriptions, TCIA will add text to Series Descriptions to help researchers during TCIA image searches. When a missing series description is encountered, TCIA staff will use the following approach: Enter “LOCALIZER” if the ImageType contains the word localizer; Enter “Contrast” and then append the value contained in Contrast Bolus Agent if a value is present; if Contrast Bolus Agent is missing or empty other tags will be examined to see if a series was scanned with contrast (The Image Comments field is often used by sites to denote contrast);  if the Image is an MR then TCIA will map the Scanning Sequence parameters into the Series Description; if none of those conditions apply then TCIA will map Scan Options or simply enter “none” into the Series Description field.

Devices - The Retain Device Identity Option of the DICOM de-identification standard allows for the retention of information related to the scanner used. The option allows for the following relevant tags to be retained: Station Name, Device Serial Number, Device UID, Plate ID, Generator ID, Cassette ID, Gantry ID, Detector ID, Scheduled Study Location, Scheduled Study Location AE Title, Scheduled Station AE Title, Scheduled Station Name, Scheduled Procedure Step Location, Performed Station AE Title, Performed Station Name, Performed Station Name Code Sequence, Scheduled Station Name Code Sequence, Scheduled Station Geographic Location Code Sequence, and Performed Station Geographic Location Code Sequence.  TCIA removes Station Name as part of its de-identification process as Station Name often contains information related to the site where the scan occurred. The other tags listed above are retained if they are found to be free of PHI after TCIA curation of the submitted DICOM objects.

Private Tags - When a submitting site sends DICOM data to TCIA all private tags are retained and then de-identified by TCIA during curation of the data according to the Retain Safe Private Option. The Retain Safe Private Option allows for the retention of DICOM tags stored in the private fields. These fields are extensively used by DICOM vendors to store information about the scans. To claim conformance to the DICOM standard the vendors must publish a DICOM conformance statement that defines the standard and private tags that are used by their particular equipment. These conformance statements are typically made available on the vendors website for download. Unfortunately, there are cases where vendors do not make the conformance statement for a piece of equipment publicly available or do not adequately define what is stored in the private tags.  In TCIA the Private DICOM elements are de-identified according to the rules contained in a de-identification knowledge base maintained by the TCIA team at the University of Arkansas for Medical Sciences.  This knowledge base defines rules for de-identification of private tags based on a vendor’s conformance statement for each scanner and software version. The manufacturer, manufacturer model, modality, and software version are extracted from each series submitted.  The TCIA de-identification knowledge base is checked for a conformance statement matching these data.  If not found, TCIA locates the conformance statement and adds it to the knowledge base.  TCIA will remove any private tags from the images that are not specified in the conformance statement or are defined as containing a form of PHI such as name, SSN, etc.  All date and datetime private tags that are retained are offset using the same offset as applied to the standard tags for the image. All private tags containing UIDs are assigned a TCIA root and appended with a hashed value as done with the standard tags. This ensures all references to other images contained within TCIA are maintained. A manual inspection of all private tags is performed using tagSniffer reports and any PHI that may be found is removed, emptied, date offset, or hashed as appropriate.

Body Part Examined - When images are made public, a single body part examined, corresponding to the cancer of interest, is assigned to all images.  If the collection consists of sarcoma images (or any other cancer affecting multiple organs within the image collection), there may be multiple body parts assigned, though only one to any series.  In phantom collections, body part examined is simply labeled “PHANTOM”.

All Tags - The TCIA de-identification process ensures that every DICOM tag of every DICOM object is free of the 18 forms of PHI as currently defined by the Safe Harbor Method.  At the submitting site, a DICOM PS 3.15 compliant script removes or modifies DIOCM tags deemed to be unsafe (See table 1 for a complete listing). At TCIA, a software routine known as tagSniffer extracts every unique value found within a collection being curated and prints them to a report. This report is examined by curators and any actions necessary to remove PHI is applied when moving the images from the Intake server to the Public Server. Every DICOM image is inspected by curators for burned in PHI. Once the images reach the Public Server, the tags are inspected by two curators for PHI using new tagSniffer reports.  Images are spot checked for any burned in PHI.

The following table details the de-identification performed at the submitting site by way of a TCIA supplied de-identification script.

Table 1

Tag

Name

Action

00080050

AccessionNumber

hash

00184000

AcquisitionComments

keep

00400555

AcquisitionContextSeq

remove

00080022

AcquisitionDate

incrementdate

0008002a

AcquisitionDatetime

incrementdate

00181400

AcquisitionDeviceProcessingDescription

keep

00189424

AcquisitionProtocolDescription

keep

00080032

AcquisitionTime

keep

00404035

ActualHumanPerformersSequence

remove

001021b0

AdditionalPatientHistory

keep

00380010

AdmissionID

remove

00380020

AdmittingDate

incrementdate

00081084

AdmittingDiagnosesCodeSeq

keep

00081080

AdmittingDiagnosesDescription

keep

00380021

AdmittingTime

keep

00102110

Allergies

keep

40000010

Arbitrary

remove

0040a078

AuthorObserverSequence

remove

00130010

BlockOwner

CTP

00180015

BodyPartExamined

BODYPART

00101081

BranchOfService

remove

00280301

BurnedInAnnotation

keep

00181007

CassetteID

keep

00400280

CommentsOnPPS

keep

00209161

ConcatenationUID

hashuid

00403001

ConfidentialityPatientData

remove

00700086

ContentCreatorsIdCodeSeq

remove

00700084

ContentCreatorsName

empty

00080023

ContentDate

incrementdate

0040a730

ContentSeq

remove

00080033

ContentTime

keep

0008010d

ContextGroupExtensionCreatorUID

hashuid

00180010

ContrastBolusAgent

keep

0018a003

ContributionDescription

keep

00102150

CountryOfResidence

remove

00089123

CreatorVersionUID

hashuid

00380300

CurrentPatientLocation

remove

00080025

CurveDate

incrementdate

Group

curves

remove

00080035

CurveTime

keep

0040a07c

CustodialOrganizationSeq

remove

fffcfffc

DataSetTrailingPadding

remove

00181200

DateofLastCalibration

incrementdate

0018700c

DateofLastDetectorCalibration

incrementdate

00181012

DateOfSecondaryCapture

incrementdate

00120063

DeIdentificationMethod

{Per DICOM PS 3.15 AnnexE. Details in 0012,0064}

00120064

DeIdentificationMethodCodeSequence

113100/113101/113105/113107/113108/113109/113111

00082111

DerivationDescription

keep

0018700a

DetectorID

keep

00181000

DeviceSerialNumber

keep

00181002

DeviceUID

keep

fffafffa

DigitalSignaturesSeq

remove

04000100

DigitalSignatureUID

remove

00209164

DimensionOrganizationUID

hashuid

00380040

DischargeDiagnosisDescription

keep

4008011a

DistributionAddress

remove

40080119

DistributionName

remove

300a0013

DoseReferenceUID

hashuid

00102160

EthnicGroup

keep

00080058

FailedSOPInstanceUIDList

hashuid

0070031a

FiducialUID

hashuid

00402017

FillerOrderNumber

empty

00209158

FrameComments

keep

00200052

FrameOfReferenceUID

hashuid

00181008

GantryID

keep

00181005

GeneratorID

keep

00700001

GraphicAnnotationSequence

remove

00404037

HumanPerformersName

remove

00404036

HumanPerformersOrganization

remove

00880200

IconImageSequence

remove

00084000

IdentifyingComments

keep

00204000

ImageComments

keep

00284000

ImagePresentationComments

remove

00402400

ImagingServiceRequestComments

keep

40080300

Impressions

keep

00080012

InstanceCreationDate

incrementdate

00080014

InstanceCreatorUID

hashuid

00080081

InstitutionAddress

remove

00081040

InstitutionalDepartmentName

remove

00080082

InstitutionCodeSequence

remove

00080080

InstitutionName

remove

00101050

InsurancePlanIdentification

remove

00401011

IntendedRecipientsOfResultsIDSequence

remove

40080111

InterpretationApproverSequence

remove

4008010c

InterpretationAuthor

remove

40080115

InterpretationDiagnosisDescription

keep

40080202

InterpretationIdIssuer

remove

40080102

InterpretationRecorder

remove

4008010b

InterpretationText

keep

4008010a

InterpretationTranscriber

remove

00083010

IrradiationEventUID

hashuid

00380011

IssuerOfAdmissionID

remove

00100021

IssuerOfPatientID

remove

00380061

IssuerOfServiceEpisodeId

remove

00281214

LargePaletteColorLUTUid

hashuid

001021d0

LastMenstrualDate

incrementdate

00280303

LongitudinalTemporalInformationModified

MODIFIED

04000404

MAC

remove

00080070

Manufacturer

keep

00081090

ManufacturerModelName

keep

00102000

MedicalAlerts

keep

00101090

MedicalRecordLocator

remove

00101080

MilitaryRank

remove

04000550

ModifiedAttributesSequence

remove

00203406

ModifiedImageDescription

remove

00203401

ModifyingDeviceID

remove

00203404

ModifyingDeviceManufacturer

remove

00081060

NameOfPhysicianReadingStudy

remove

00401010

NamesOfIntendedRecipientsOfResults

remove

00102180

Occupation

keep

00081070

OperatorName

remove

00081072

OperatorsIdentificationSeq

remove

00402010

OrderCallbackPhoneNumber

remove

00402008

OrderEnteredBy

remove

00402009

OrderEntererLocation

remove

04000561

OriginalAttributesSequence

remove

00101000

OtherPatientIDs

remove

00101002

OtherPatientIDsSeq

remove

00101001

OtherPatientNames

remove

00080024

OverlayDate

incrementdate

Group

overlays

remove

00080034

OverlayTime

keep

00281199

PaletteColorLUTUID

hashuid

0040a07a

ParticipantSequence

remove

00101040

PatientAddress

remove

00101010

PatientAge

keep

00100030

PatientBirthDate

empty

00101005

PatientBirthName

remove

00100032

PatientBirthTime

remove

00104000

PatientComments

keep

00100020

PatientID

Re-Mapped

00120062

PatientIdentityRemoved

YES

00380400

PatientInstitutionResidence

remove

00100050

PatientInsurancePlanCodeSeq

remove

00101060

PatientMotherBirthName

remove

00100010

PatientName

Re-Mapped

00102154

PatientPhoneNumbers

remove

00100101

PatientPrimaryLanguageCodeSeq

remove

00100102

PatientPrimaryLanguageModifierCodeSeq

remove

001021f0

PatientReligiousPreference

remove

00100040

PatientSex

keep

00102203

PatientSexNeutered

keep

00101020

PatientSize

keep

00380500

PatientState

keep

00401004

PatientTransportArrangements

remove

00101030

PatientWeight

keep

00400243

PerformedLocation

remove

00400241

PerformedStationAET

keep

00404030

PerformedStationGeoLocCodeSeq

keep

00400242

PerformedStationName

keep

00404028

PerformedStationNameCodeSeq

keep

00081052

PerformingPhysicianIdSeq

remove

00081050

PerformingPhysicianName

remove

00400250

PerformProcedureStepEndDate

incrementdate

00401102

PersonAddress

remove

00401101

PersonIdCodeSequence

remove

0040a123

PersonName

empty

00401103

PersonTelephoneNumbers

remove

40080114

PhysicianApprovingInterpretation

remove

00081048

PhysicianOfRecord

remove

00081049

PhysicianOfRecordIdSeq

remove

00081062

PhysicianReadingStudyIdSeq

remove

00402016

PlaceOrderNumberOfImagingServiceReq

empty

00181004

PlateID

keep

00400254

PPSDescription

keep

00400253

PPSID

remove

00400244

PPSStartDate

incrementdate

00400245

PPSStartTime

keep

001021c0

PregnancyStatus

keep

00400012

PreMedication

keep

Group

privategroups

keep

00131010

ProjectName

always

00181030

ProtocolName

keep

00540016

Radiopharmaceutical Information Sequence

process

00181078

Radiopharmaceutical Start DateTime

incrementdate

00181079

Radiopharmaceutical Stop DateTime

incrementdate

00402001

ReasonForImagingServiceRequest

keep

00321030

ReasonforStudy

keep

04000402

RefDigitalSignatureSeq

remove

30060024

ReferencedFrameOfReferenceUID

hashuid

00380004

ReferencedPatientAliasSeq

remove

00080092

ReferringPhysicianAddress

remove

00080090

ReferringPhysicianName

empty

00080094

ReferringPhysicianPhoneNumbers

remove

00080096

ReferringPhysiciansIDSeq

remove

00404023

RefGenPurposeSchedProcStepTransUID

hashuid

00081140

RefImageSeq

remove

00081120

RefPatientSeq

remove

00081111

RefPPSSeq

remove

00081150

RefSOPClassUID

keep

04000403

RefSOPInstanceMACSeq

remove

00081155

RefSOPInstanceUID

hashuid

00081110

RefStudySeq

remove

00102152

RegionOfResidence

remove

300600c2

RelatedFrameOfReferenceUID

hashuid

00400275

RequestAttributesSeq

remove

00321070

RequestedContrastAgent

keep

00401400

RequestedProcedureComments

keep

00321060

RequestedProcedureDescription

keep

00401001

RequestedProcedureID

remove

00401005

RequestedProcedureLocation

remove

00321032

RequestingPhysician

remove

00321033

RequestingService

remove

00102299

ResponsibleOrganization

remove

00102297

ResponsiblePerson

remove

40084000

ResultComments

keep

40080118

ResultsDistributionListSeq

remove

40080042

ResultsIDIssuer

remove

300e0008

ReviewerName

remove

00404034

ScheduledHumanPerformersSeq

remove

0038001e

ScheduledPatientInstitutionResidence

remove

0040000b

ScheduledPerformingPhysicianIDSeq

remove

00400006

ScheduledPerformingPhysicianName

remove

00400001

ScheduledStationAET

keep

00404027

ScheduledStationGeographicLocCodeSeq

keep

00400010

ScheduledStationName

keep

00404025

ScheduledStationNameCodeSeq

keep

00321020

ScheduledStudyLocation

keep

00321021

ScheduledStudyLocationAET

keep

00321000

ScheduledStudyStartDate

incrementdate

00080021

SeriesDate

incrementdate

0008103e

SeriesDescription

keep

0020000e

SeriesInstanceUID

hashuid

00080031

SeriesTime

keep

00380062

ServiceEpisodeDescription

keep

00380060

ServiceEpisodeID

remove

00131013

SiteID

SITEID

00131012

SiteName

SITENAME

001021a0

SmokingStatus

keep

00181020

SoftwareVersion

keep

00080018

SOPInstanceUID

hashuid

00082112

SourceImageSeq

remove

00380050

SpecialNeeds

keep

00400007

SPSDescription

keep

00400004

SPSEndDate

incrementdate

00400005

SPSEndTime

keep

00400011

SPSLocation

keep

00400002

SPSStartDate

incrementdate

00400003

SPSStartTime

keep

00081010

StationName

remove

00880140

StorageMediaFilesetUID

hashuid

30060008

StructureSetDate

incrementdate

00321040

StudyArrivalDate

incrementdate

00324000

StudyComments

keep

00321050

StudyCompletionDate

incrementdate

00080020

StudyDate

incrementdate

00081030

StudyDescription

keep

00200010

StudyID

empty

00320012

StudyIDIssuer

remove

0020000d

StudyInstanceUID

hashuid

00080030

StudyTime

keep

00200200

SynchronizationFrameOfReferenceUID

hashuid

0040db0d

TemplateExtensionCreatorUID

hashuid

0040db0c

TemplateExtensionOrganizationUID

hashuid

40004000

TextComments

remove

20300020

TextString

remove

00080201

TimezoneOffsetFromUTC

remove

00880910

TopicAuthor

remove

00880912

TopicKeyWords

remove

00880906

TopicSubject

remove

00880904

TopicTitle

remove

00081195

TransactionUID

hashuid

00131011

TrialName

PROJECTNAME

0040a124

UID

hashuid

Group

unspecifiedelements

keep

0040a088

VerifyingObserverIdentificationCodeSeq

remove

0040a075

VerifyingObserverName

empty

0040a073

VerifyingObserverSequence

remove

0040a027

VerifyingOrganization

remove

00384000

VisitComments

keep

 

More Details regarding TCIA de-identification may be found at the following links: De-Identification Rules.