ITK/Release 4/DICOM/Tcon 2010 10 11

Attendees

• Mathieu Malaterre (CoSMo)
• Steve Pieper (Isomics)

Topics

• DICOM Query/Retrieve API (C-ECHO, C-STORE, C-MOVE, C-FIND):
  • http://github.com/malaterre/ITKDICOM
• Should we support streaming ?
  • Store to disk (easy) ?
  • Store to memory (harder) ?
    • Drop Presentation Data Value for Pixel Data (requested extent) ?
    • JPIP ?
• Interface for Abstract DICOM DataSet /
  • Follow App 118 syntax (see below)
  • Very simple interface (eg. vtkMedicalImageProperties). Not extensible
  • Flexible solution to handle PMS and CSA:
    • http://sourceforge.net/apps/mediawiki/gdcm/index.php?title=Gdcmdump#SIEMENS_CSA_Header
    • http://sourceforge.net/apps/mediawiki/gdcm/index.php?title=Gdcmdump#Protocol_Data_Block
• C-FIND interface ?
  • low level DICOM approach: http://www.itk.org/Wiki/DICOM_QueryRetrieve_Explained
  • interface for characterset (easy work around only allow UTF-8 interface)

• Implementation details:
  • Support GDCM ?
  • Support DCMTK ?
  • Support CTN ?
  • Third party ?
• Should we support Extensions:
  • kerberos ?
  • TLS ?

SubTopics

• Relation: itk::Image / itk::DICOMDataSet
  • This is a weak relation
  • http://www.itk.org/Wiki/ITK_Release_4/Image_Class_Hierarchy_Refactoring

• How do we handle 2D DICOM Series loaded in a Single itk::Image ? (one DataSet ? array of dataset ?)
• How do we handle the opposite : 3D image stored as 2D (Eg. Enhanced -> old SOP)
• Typical use case: Applying Gaussian filter on itk::Image, means changing Image Type from ORIGINAL to SECONDARY...
  • Should we remove attribute from Image group (0028) ?
  • Question: how do we hanlde Overlay stored in Pixel Data unused bits ?

Annex: App 118 Syntax

See:

• ftp://medical.nema.org/medical/dicom/supps/sup118_lb.pdf

A.1.7 Examples

Here is an example XPath query to extract the code meaning of the first item in the View Code Sequence:
/DicomNativeModel/DicomAttribute[@keyword=‖ViewCodeSequence‖]/Item[@number=1]/ /DicomAttribute[@keyword=‖CodeMeaning‖]/Value[@number=1]
1405

See posts

• http://lists.nema.org/scripts/lyris.pl?sub=488573&id=443986901

> The following XPath expression is not defined:
>
> DicomAttribute[@tag=”OverlayLabel”]/Value[@number=1]
>
DicomAttribute[@tag=”OverlayLabel” and @repeating="02"]/Value[@number=1]