PPT Template for Diagnostic Imaging

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What is Canada doing about Lossy Compression?
Peter R.G. Bak, Ph.D. Project Director,
Diagnostic Imaging and Laboratory
Architecture Canada Health Infoway 15 February,
2006
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Disclosures

• Peter R.G. Bak is a consultant working for Canada
  Health Infoway

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Lossy Compression in Canada

• Canadian Association of Radiologists (CAR) have
  endorsed the use of lossy compression in
  principle
• CAR intends to fully endorse lossy compression as
  a standard of practice by end of 2006
• Confirm that lossy compression does not impact
  visual quality through clinical evaluation
• Develop practice/ratio guidelines to assist
  radiologists/health authorities with
  implementation

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Context The Motivation for Compression

• Canada has initiated the deployment of a
  pan-Canadian interoperable Electronic Health
  Record solution (EHRs)
• Canada Health Infoway (Infoway) is an
  independent, not for profit corporation
  responsible for developing the architecture of
  the EHRs
• A core component of a patients health record is
  the diagnostic imaging result medical images,
  radiology reports and evidence documents
• Canada is moving aggressively towards a fully
  filmless medical imaging environment we want to
  print less than 2 of our exams

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Context The Motivation for Compression

• Canada performs about 35,000,000 exams annually
• This equates to about 3.5PB of storage annually
• We have an aging population expect an increase
  in exam volume and CT utilization
• Canadian healthcare facilities are widely
  dispersed across a large geography
• Over 540 facilities (lt100 beds) in rural Canada
• Network connectivity is limited most rural
  areas have 1mbps connectivity
• Canadian Radiologists and Specialists are
  centered in the larger metropolitan cities
• The challenge is getting images from rural
  facilities to metropolitan centres in a timely
  manner

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Context The Motivation for Compression

• Storage Costs
• Storage costs are coming down but the storage
  volume is going up
• We expect consumption increase will offset price
  decrease
• Storage costs are significant (50M) but not
  significant enough to drive change!
• Storage Total Cost of Ownership is far more
  significantenough to drive change!
• Infoway is completing an economic assessment that
  indicates significant cost savingsyet to be
  completed and published!
• Network Costs
• Increasing bandwidth to rural areas is practical
  up to 5mbps (more or less)
• Increasing bandwidth to rural areas at rates of
  100mbps is not going to happen in the foreseeable
  future
• Compression will have a positive impact on
  quality of care and cost

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Challenging the Status Quo

• Lossy compression does NOT degrade image quality
  and can be used safely in daily practice!

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The Canadian Approach to Driving Change

• Commissioned 2 independent reviews of the
  literature
• To assess the degree of research conducted in the
  evaluation of lossy compression
• To determine whether a consensus of opinion
  exists among those who have evaluated the effect
  of lossy compression on diagnostic image quality
• Conclusion
• Lossy compression is a clinically acceptable
  option for the compression of medical images
• The extent of allowable lossy compression ratio
  is dependent on the modality of the image and the
  nature of the imaged pathology and anatomy

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The Canadian Approach to Driving Change

• Commissioned 2 independent legal reviews
• To assess the legal risk of adopting lossy
  compression
• Conclusion
• If the professional body adopts lossy compression
  as a standard of practice, and
• If institutions deem the use of lossy compression
  provides economic and practical operational
  benefits as well as contributes to better quality
  care,
• Then the exposure to legal risk is no greater
  than with current practice.
• The key presumption, however, is that the use of
  lossy compression does not impact the visual
  quality of an image

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The Canadian Approach to Driving Change

• Commissioned 1 regulatory review
• To assess regulatory constraints in Canada, USA,
  EU and Australia
• Conclusion
• No statements preventing or endorsing the use of
  irreversible compression
• Commissioned an economic analysis
• To assess the financial benefit to Canada in
  using lossy compression
• Conclusion
• Potential storage cost savings of C100 million
  annually

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The Canadian Approach to Driving Change

• Commissioned clinical evaluation
• To assess the impact of lossy compression on
  visual quality
• To develop guidelines for use of lossy
  compression within Canada
• In Progresscompletion targeted for end 2006

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The Canadian Approach to Driving Change

• Evaluation Project Scope
• Evaluate the impact of JPEG and JPEG 2000 lossy
  compression at safe compression ratios
• Large matrix images 251
• Small matrix images 101
• Evaluation Project Protocol
• Diagnostic accuracy with ROC analysis
• Original Revealed First Choice Just Noticeable
  Difference
• 27 different sessions, with 3 reviewers for each
• 81 radiologists from all across Canada
• Sample size for each session will be 60 to 80
  images.
• 5 modalities CR/DR, CT, US, MR, NM
• 7 radiological areas Angio, Body, Breast, Chest,
  MSK, Neuro, Pediatrics)

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The Canadian Approach to Driving Change

• Solicited Regional Health Authority
  Administrations
• To declare the use of lossy compression a matter
  of public policy and resource allocation
• In Progress
• Fraser Health Authority (largest HA in Canada)
  has made such a declaration
• In discussion with Provincial Health Ministries

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Conclusion

• We expect CAR to formally endorse lossy
  compression as a standard of practice by year end
• We expect most Provincial health ministries to
  declare the use of lossy compression as a matter
  of public policy and resource allocation by end
  of 2007
• We will declare DICOM JPEG, JPEG2000 and JPIP as
  pan-Canadian standards
• Canada has a Standards Collaboration Process for
  declaring standards for the pan-Canadian EHR
• We will implement a reference system to serve as
• An open source test harness
• A standards compliance tool

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Questions?