FDG-PET/CT Technical Committee

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FDG-PET/CT Technical Committee

• Quality Control Subcommittee

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Goals

• Bridge the gap between PET/CT scanner
  acceptance/qualification/certification and
  routine (daily) quality control
• Summarize methods and parameters for evaluating
  daily PET and CT QC on each vendors PET/CT
  scanner
• Long term goal Establish common standards for
  recording and distributing QC parameters for
  individual patient scans (e.g. extended DICOM
  tags)

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Process

1. Identify the daily quality control tests that are
   performed on each vendors PET/CT scanners
2. Specify the range of acceptable parameters for
   each test as recommended by the vendor
3. Describe the methods for obtaining QC parameters
   and the output format for each vendor
4. Ideally, develop standard for daily QC output
   that could be exported with individual patient
   scan, e.g. extended DICOM tags or standard file
   format (CSV, XML)

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CT Quality Control

• Siemens automated test (pass/fail)
• Check HU value of water.
• Check pixel noise
• Check tube voltages
• GE manual test with acceptable range
• Check mean CT value of water (range 0 3 HU) in
  3 ROIs of uniform section.
• Check variance of water (range 3 0.4) in 3 ROIs
  of uniform section

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Siemens PET Quality Control

• Ge-68 cylinder compared to normalization standard
• Visually inspect sinograms and fansums.
• If a sinogram shows a dark or bright streak or a
  fansum block is not uniform, notify physicist
• If Chi-square gt 2.5, notify physicist. (Original
  limit, adopted as DFCI threshold.)
• If Chi-square gt 10, call Service. Notify physicist

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GE PET Quality Control

• Ge-68 pin source compare daily tests to baseline
  with color coded results (green/yellow/red)
• Coincidence mean (sensitivity test Average of
  coincidences for all crystals)
• Coincidence variance
• Singles mean (Average of singles for all
  crystals).
• Singles variance
• Mean deadtime (Average deadtime of all blocks).
• Timing mean (Average timing adjustment of all
  crystals)
• Energy shift (Average difference in energy peak
  location)

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QC Output formats

• Mostly based on visual display
• Siemens has some files available in html format
  on local folder
• GE results can be printed as postscript

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Resources Needed

• Information about Philips Daily QC from end users
  and vendor
• Additional clarifications from GE and Siemens
• Feedback from RSNA QIBA members
• Potential interactions with DICOM working group
  to discuss inclusion of QC results