The Importance of IHE Cardiology Profiles Herman Oosterwijk
IHE: What is IHE? What is IHE NOT? The Cardiology profile descriptions Conclusion
What is IHE? Joint activity by Radiological Society of North America (RSNA) and Hospital Information Management Systems Society (HIMSS) Initially defined for Radiology domain, extended to Cardiology and IT infrastructure; future EHR? Definition of actors: consistent terminology, functionality and features, to avoid overlap and/or gaps Definition of transactions, including their contents
What is IHE? (cont.) Recommended choices in case there is more than one way of doing things (scoutview, query) Actors and transaction, and sequencing and contents Profiles Series of demonstrations and annual connectathon with published results Test tools AND test images to test compliance Generally used by majority of users to request certain functionality in RFP s: simplification of requirements
What is IHE NOT? It is NOT a validation or certification It is NO guarantee to interoperability There is NO IHE Police (such as there is no DICOM or HL7 police) It is NOT a standard Rather it is: An implementation framework It increases your chance for interoperability It specifies uses cases, i.e. real world scenarios with the appropriate standards Integration statements, on vendor or RSNA site
The Technical Framework: Functions as the core technical specification: defines profiles Four sets defined: IHE Cardiology TF IHE IT Infrastructure TF IHE Radiology TF IHE Laboratory TF
Cardiology Challenge:
Cardiology Profiles: 1. Cath lab workflow 2. Echo workflow 3. View ECG s Build on ITI and also radiology profiles
Cardiac Catheterization Workflow (CATH): Mechanism to manage and distribute workflow within cardiology department cath labs across the several types of equipment in a synchronized manner Often no orders placed (emergency!) Variety of imaging, measuring and reporting systems Combination of diagnostic, interventional and therapeutic
Cardiac Catheterization Workflow (CATH): Establishes continuity and integrity of patient data Scheduling and procedure data across variety of systems Reliable storage of all information Central coordination of the completion status Includes IVUS (intra-vascular) and ICE (intracardiac) Ultrasound
Scheduled Workflow (Radiology):
Actors: (same as defined for radiology) ADT Order Placer Order Filler Acquisition Modalities Image Archive Image Manager MPPS Manager Viewer
Scheduled Workflow Transactions for Cardiology: 1: Patient Registration 2: Placer Order Management 3: Filler Order Management 4: Procedure Scheduled 5: Query Modality Worklist 6: Modality Procedure Step in Progress 7: Modality Procedure Step Completed/Discontinued 8: Modality Images/Evidence Stored 10: Storage Commitment 11: Patient Update 12: Procedure Update 13: Query Images 14: Retrieve Images 18: Maintain Time 19: Retrieve ECG List 20: Retrieve ECG Document for Display
What is Different from Radiology (Scheduling)? The Department System Scheduler (DSS)/Order Filler may start the cath procedure: allow collection of patient data; typically result in Arrived Status MWL query will most likely take place through Patient ID query using wristband
What is Different from Radiology (Procedure)? MPPS in progress: Procedure might be scheduled in different room; All scheduled procedure steps for all modalities in the cath lab are updated The image manager has to support not only images but also waveforms, analysis reports, etc. Some of the modalities are mobile, therefore, managing the Storage Commitment responses might be intermittent ( upon connection )
Use Cases: Clinical perspective: typically, cardiologist makes arrangement over the phone for a CATH, mostly identified on a white-board Patient reconciliation is no exception, but, rather a rule
Use Cases: Order at order entry system - similar to radiology Order at department system - updates HIS No order (identifiers are typically entered at first modality (hemodynamics) and than shared No Patient registration temporary ID is assigned and entered at first modality which is shared; reconciliation takes place later Unidentified Patient updates take place during procedure (update message) Change room during procedure: makes sure to identify as a single Image Service Request
Scheduled Workflow Storage Commitment Acquisition Modality DICOM Storage Commitment N-ACTION DICOM Storage Commitment N-EVENT-REPORT Image Manager Example transaction diagram
Echo Workflow (ECHO): Mechanisms to manage and distribute the workflow within the cardiology department echocardiography function. Includes TTE (thoracic), TEE (esophageal) and stress echo As with CATH profile, deals with Patient Identification, orders, scheduling, reporting, multi-stage exams (stress) and data storage Also deals with portable units
ECHO: TTE: Trans Thoracic Echocardiography: Usually performed by sonographers, reviewed off-line by cardiologists Often done using mobile units (carts: issuemaybe disconnected over period of time) Typically verbally ordered Often emergency cases
ECHO (cont.): TEE: Transesophageal Echocardiography: Usually performed by cardiologists Not typically unscheduled Requires staff, room, equipment Images and information about the procedure gathered
ECHO (cont.): Stress Echocardiography: Typically scheduled Information about the stress used is recorded Response to stress is recorded (blood pressure, heart rate, symptoms, ECG changes)
Use Cases: Intermittently connected modality: depends on shift and/or can be turned off Modality worklist is downloaded at beginning of round No MPPS messages are possible; sent in batch upon reconnection Images also sent in batch as well as Storage Commitment
Use Cases: Staged protocol Stress echo: Two or more intervals or stages are used with images ( views ) containing a particular cross section Stress is typically inuced by excersise or medication Typically baseline, mid stress, peak stress and recovery stages Stages are typically considered as part of the same procedure Step
Retrieve ECG for Display (ECG): This profile provides access through enterprise to ECG documents for review. Includes diagnostic quality waveforms, measurements and interpretations Allows display using a simple browser Mainly for resting 12 lead ECG, couls also include Holter,s tress, etc. NO ordering, acquiring, etc. included, mainly retrieving and viewing
Transactions/Details: Retrieve ECG List Retrieve ECG document for display Different requests, e.g. based on Pat ID could have different content, e.g. different ECG s Web Service Definition defined: XML encoding, and Unique Identifier
ECG List XML Example Formatted with Stylesheet: Slide courtesy of IHE workshop
ECG List XML Example Simple Serial Comparison App: Slide courtesy of IHE workshop
Serial Comparison Example: 23-April-2004 13:47:45 Slide courtesy of IHE workshop
Special concerns: Grouped procedures-group case Use a Single Requested Procedure (single Study Instance UID): Could be multiple reports (similar to mammography: double reads) Single procedure : patient on the table Makes it simple in case diagnostic changes to interventional Note: could have separate MPPS steps
Accession Number Order Filler Number Study SOP Instance UID Study Inst. UID Patient Requested Procedure ID Study Inst.UID Imaging Serv. Req. (Order) Requested Procedure Scheduled Procedure Step Study Mgt Performed Procedure Step Study Series Inst. UID Sched. Proc. Step ID Perf. Proc. Step ID Perf. Proc. Step UID (i.e. SOP Inst UID) Series Series Image Image Image Image Image Image SOP Instance UID
In Short, IHE Provides: A path towards greater level of interoperability An excellent resource for users to specify functionality (Use this as an opportunity!) Important resource in a multi-vendor environment for connecting Modalities, PACS, RIS and facilitate enterprise distribution More definitions of multiple domains outside Radiology (Cardiology), including the IT infrastructure (Security), to migrate to EHR
More Information on IHE: www.rsna.org/ihe Papers Specifications Presentations IHE is critical for connectivity!