Waveform, Workflow, Archiving

1
Waveform, Workflow, Archiving

• Assessment of Standard Interfaces
• Opportunities for Cooperation

2
Three Levels for Connectivity Standards
DeviceConnectivity
DepartmentalIntegration
Hospital/AmbulatoryWorkflow EMR Integration
RISR-PACS
Radiology
Imaging Modalities Image proc. CAD,
DICOM
Enterprise Archive
ADTOrder Placer EMR,
DICOM
CardiacIS, C-PACS
Rest, Stress, Holter ECG
Cardiology
Cardiac MonitorsHemodynamics
Captors, Actuators
Bed-SideMonitors
ICUIS
ClusterMonitor
ICU
SCP ? HL7 ?DICOM ?1073 ?
1073
HL7

• Three Examples ? Overlap ? Coordination Needed

3
Three Topics, Three Opportunities ?

1. Persistent Waveform Objects
2. Departmental Workflow Integration
3. Enterprise Archiving of Images Waveforms

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DICOM WaveformsQuick Refresher
5
Key Aspects of DICOM

• DICOM domain is communications for imaging-based
  care
• DICOM is an Object-based standard
• Persistent objects
• Inter-object referential capability
• Binary tagged data element format
• Objects are hierarchically organized
• Patient / Study / Series (modality) folders
• DICOM Persistent Object workflow services over
  TCP/IP
• Generally in client-server architecture
• Object transfer, storage, storage commitment,
  query and retrieval
• Media-Interchange (CD, DVD, Floppy, etc.) with
  clinical directory.
• Network Archiving
• Departmental workflow management (worklist,
  performed steps)
• Broadly used and accepted world-wide for many
  years.

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DICOM Waveforms

• Supplement 30 Waveform in DICOM 2001
• Introduces general structure for waveform
  composite (persistent) objects
• Waveform channels identified by coded-entry
  triplet
• Coding Scheme / Code Value / Code Meaning
• Allows externally defined terminology (e.g.,
  SCP-ECG for leads)
• Triplets also used in HL7 and DICOM Structured
  Reporting
• Triplet values may be constrained by Templates
  defined in Part 16
• Specific waveform Object Definitions
  (particularly for cardiology)
• Hemodynamics
• Cardiac Electrophysiology
• Electrocardiography (12-lead, ambulatory,
  general)
• Basic Voice Audio
• In progress, Ultrasound Doppler Waveform (Suppl
  56)

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DICOM Waveform Object

• Waveform object encodes digital data from a
  discrete time period
• Multiple channels all channels have common time
  base
• Flexible waveform sample format
• 8 or 16 bit data Signed, unsigned, u-law, A-law
• Separate sampling frequencies for each channel,
  or multiplexed channels at common frequency
• Objects may be temporally contiguous, or
  temporally selective
• Store and forward (not for real time
  monitoring)
• Waveform object encodes full definition of each
  channel
• Quality being sampled, Sensor location
  (anatomic),Function (measurement or stimulus),
  Resolution and range, Technique (e.g., pull-back)
• Based on HL7 V2 definition
• Waveform object encodes DICOM HL V2 context
  information in header
• Equipment information (manufacturer, serial
  number, location)
• Temporal frame of reference (synchronization with
  other objects, in particular images)
• Waveform object encodes optional annotation
• Identify features or regions of interest
• Generated by acquisition unit
• Constructed of label and time or sample reference

Streams of Waveform Samples
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Waveforms Standardization for Departemental
Integration-Key Objectives-
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Waveforms why integrated separated ?

• Integrated with other persistent objects
• Images
• Supporting the waveforms (e.g., for documentation
  of EP catheter location)
• Supported by waveforms (e.g., simultaneous ECG
  for IVUS post processing)
• Various categories of Structured Reports with
  waveform references.
• Clinical reports
• Measurement reports (e.g., hemodynamics, or ECG)
• Procedure Log documents (full procedural context
  for waveform acquisition)
• Key object selection (electronic Post-It)
• Workflow integration
• worklists and status monitoring of scheduled
  tasks
• including distribution of patient demographics
• Object archiving and retrieval Key for
  archiving of recorded vitals signs
• Web accessible as persistent objects (presented
  or original data)
• Focused on Full Fidelity Acquired Data
• No Presentation to be addressed independently.
• Compression compact encoding, separate from the
  object definition
• Clearly distinguished from derived measurements
  and reports
• Patient/Visit/Order context driven by HL7

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Departmental Workflow Integration DICOM and
HL7.. Much more than combining standards !
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IHE Scheduled Workflow
RIS
PACS Archive

• A Closed Loop
• Update IS Scheduling
• Match Procedure with Order
• Support Billing Based on MPPS
• Avoid Reading incomplete Procedures

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Structuring the Departmental Workflow with an
Enterprise perspective
Radiology Department
ORDER A request for RadiologicService
Set of Codifiable, Billable, Acts
Requested Procedure 1
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What is IHE ?

• An Initiative Sponsored by Users HIMSS plus
  clinical societies (e.g.RSNA)
• Active Industry Leadership, shaping direction
• Leverage existing standards (HL7, IEFT, DICOM,
  etc.) in an industry defined integration
  framework
• Proceed in pragmatic incremental steps to deliver
  easier to integrate product implementations
• Proven approach in IT Radiology (over 100
  vendors already participate).

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Enterprise Archiving of Images and Waveforms
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IHE Integration Profiles
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What is Unique about IHE ?

• A User/Vendor Team Effort
• Voluntary and Open to All Vendors. It is not a
  consortium.
• Professional Associations Engaged (e.g. HIMSS
  leadership)
• Starts from concrete user integration needs,
  selects standards, sets a technical framework,
  provides a test-bed, and demonstrates/educates
  marketplace.
• Does not define product architectures or
  features, only the glue between products.
• Successful. Benefits both small and large
  vendors, worldwide North America, Europe, Asia.

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Industry is invited to shape and expand IHE

• A kick-off meeting in order to
• Review the current state of integration in the
  healthcare information technology industry
• Identify IT Infrastructure priorities necessary
  for building an EMR
• Establish the structure and timeline for
  implementation.
• All vendors are invited
• Product marketing technical leadership
• When where
• November 4-5, 2002
• Malvern, (near Philadelphia, PA)
• Respond to invitation ihe_at_rsna.org

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IHE Scheduled Workflow
RIS
PACS Archive

• A Closed Loop
• Update IS Scheduling
• Match Procedure with Order
• Support Billing Based on MPPS
• Avoid Reading incomplete Procedures

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Enterprise Archiving of Images and Waveforms
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Enterprise Archiving for complex clinical data
images and waveforms

• Large and "specialized" complex clinical data
  sets call for archiving outside of central EMR
  database
• Images are being handled by PACS (radiology,
  cardiology, etc.) and hospital wish to also share
  resource for waveforms
• A consistent set of standards is required to
  achieve this integration of image and waveform
  enterprise archiving in an EMR driven environment.

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Enterprise ArchivingDICOM 10 years of
experience
Media Interchange (Inst. DIR)
EnterprisePersistent Objects Repository
Store (Class/Instance UID)
DepartmentalIS System RIS, PACS, CIS, etc.
Storage Commitment
Retrieve (Instance UID)
Store (Class/Instance UID)
Transparent Persistent Object Payload (except for
Class)
Study/Patient
Query (Study Root)
Series
PersistentObject Instance
WebAccess Native or presented forms
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Web Access to Persistent DICOM Objects
e.g.EPR
Persistent Objects Repository
"Form ofthe reference"
"Form ofthe reference"
Retrieve a "presentation view"
Client AccessingHealthcareDocuments
Retrieve a "Data Set"
Data Set "Retrieve" -Preferred transfer
Syntax -Default transfer Syntax ?
Presentation View "Retrieve" -Type of encoding
for images (JPEG, GIF, etc.) -Type of document
presentation format (PDF, HTML, CDA-L1) -Size of
Images

• Retrieve one "entire document" (either in a
  presentation view or as a data set) using its
  "Persistent Document Instance UID"

• Intent is not to offer a "Query"
• Need is only to get access to an object

23
Waveforms Standardization for Departemental
Integration-Key Objectives-
24
Waveforms why integrated separated ?

• Integrated with other persistent objects
• Images
• Supporting the waveforms (e.g., for documentation
  of EP catheter location)
• Supported by waveforms (e.g., simultaneous ECG
  for IVUS post processing)
• Various categories of Structured Reports with
  waveform references.
• Clinical reports
• Measurement reports (e.g., hemodynamics, or ECG)
• Procedure Log documents (full procedural context
  for waveform acquisition)
• Key object selection (electronic Post-It)
• Workflow integration
• worklists and status monitoring of scheduled
  tasks
• including distribution of patient demographics
• Object archiving and retrieval Key for
  archiving of recorded vitals signs
• Web accessible as persistent objects (presented
  or original data)
• Focused on Full Fidelity Acquired Data
• No Presentation to be addressed independently.
• Compression compact encoding, separate from the
  object definition
• Clearly distinguished from derived measurements
  and reports
• Patient/Visit/Order context driven by HL7