FrameVOILUTSequence on PerFrameFunctionalGroupsSequence

[paolom]

Hi,
I want to apply a FrameVOILut on a Multiframe Dicom Images.
This is a piece of DICOM that contains one item of FrameVOILUTSequence

Code: Select all

(5200,9230) SQ (Sequence with explicit length #=34)     # 10948, 1 PerFrameFunctionalGroupsSequence
  (fffe,e000) na (Item with explicit length #=4)          # 314, 1 Item
    (0018,9504) SQ (Sequence with explicit length #=1)      #  98, 1 XRay3DFrameTypeSequence
      (fffe,e000) na (Item with explicit length #=5)          #  90, 1 Item
        (0008,9007) CS [DERIVED\PRIMARY\VOLUME\NONE]            #  28, 4 FrameType
        (0008,9205) CS [MONOCHROME]                             #  10, 1 PixelPresentation
        (0008,9206) CS [VOLUME]                                 #   6, 1 VolumetricProperties
        (0008,9207) CS [NONE]                                   #   4, 1 VolumeBasedCalculationTechnique
        (0020,9536) US 1                                        #   2, 1 ReconstructionIndex
      (fffe,e00d) na (ItemDelimitationItem for re-encoding)   #   0, 0 ItemDelimitationItem
    (fffe,e0dd) na (SequenceDelimitationItem for re-encod.) #   0, 0 SequenceDelimitationItem
    (0020,9111) SQ (Sequence with explicit length #=1)      #   8, 1 FrameContentSequence
      (fffe,e000) na (Item with explicit length #=0)          #   0, 1 Item
      (fffe,e00d) na (ItemDelimitationItem for re-encoding)   #   0, 0 ItemDelimitationItem
    (fffe,e0dd) na (SequenceDelimitationItem for re-encod.) #   0, 0 SequenceDelimitationItem
    (0020,9113) SQ (Sequence with explicit length #=1)      #  42, 1 PlanePositionSequence
      (fffe,e000) na (Item with explicit length #=1)          #  34, 1 Item
        (0020,0032) DS [-66.7081\-73.6117\-62.2063]             #  26, 3 ImagePositionPatient
      (fffe,e00d) na (ItemDelimitationItem for re-encoding)   #   0, 0 ItemDelimitationItem
    (fffe,e0dd) na (SequenceDelimitationItem for re-encod.) #   0, 0 SequenceDelimitationItem
    (0028,9132) SQ (Sequence with explicit length #=1)      # 118, 1 FrameVOILUTSequence
      (fffe,e000) na (Item with explicit length #=4)          # 110, 1 Item
        (0028,1050) DS [5138\5138\5058\5169]                    #  20, 4 WindowCenter
        (0028,1051) DS [1594\1594\1753\1434]                    #  20, 4 WindowWidth
        (0028,1055) LO [CURRENT\STANDARD\SMOOTH\CONTRAST]       #  32, 4 WindowCenterWidthExplanation
        (0028,1056) CS [LINEAR]                                 #   6, 1 VOILUTFunction
      (fffe,e00d) na (ItemDelimitationItem for re-encoding)   #   0, 0 ItemDelimitationItem
    (fffe,e0dd) na (SequenceDelimitationItem for re-encod.) #   0, 0 SequenceDelimitationItem
  (fffe,e00d) na (ItemDelimitationItem for re-encoding)   #   0, 0 ItemDelimitationItem

The DicomImage getVoiLutCount() and getVoiLutFunction() returns 0.

How can I apply this VOILut? Is it possible?

Thanks

[Michael Onken]

Hi,

applying this VOI LUT is not automatically possible. You will have to read the values and apply them yourself by using the setters on the DicomImage class.

Note that DCMTK contains now a a new module called "dcmfg" which makes it easier and more explicit for you to access values from functional group.

In the future, dcmimgle/dcmimage should automatically use dcmfg (or another approach) to extract the VOI LUT information from the functional groups.

Best,
Michael

[paolom]

Which setter do I use?

I've tried with setVoiLUT() but it doesn't work.

Do I need to apply individually windowCenter and windowWidth and not the entire VOI LUT?

[Michael Onken]

Hi,

try setWindow() and use corresponding pairs of WindowCenter and WindowWidth.

Best,
Michael