1. Managing the Acquisition Workflow
Nikolaus Wirsz, PhD
Siemens Healthcare Member of the DICOM Standards Committee and Working Group Ten – Strategic Advisory

2. Managing the Acquisition Workflow
Introduction
Modality Worklist
Modality Performed Procedure Step
Storage Commitment
Instance Availability Notification
Conclusions
April 8-10, 2008
DICOM International Conference & Seminar

3. DICOM International Conference & Seminar
Introduction
DICOM Constructs
Information Object Definitions (IOD): Images, Evidence Documents
Service Class Specifications: Storage, Query/Retrieve, …
Data Structures and Semantics
Message Exchange …
… to support
User Tasks
Interactions Between Systems
Process Steps in the Diagnostic Chain
… and improve clinical processes:
Acquisition Workflow
Post-Processing Workflow
Reporting Workflow
The DICOM Standards define a variety of elements – Service Class Specifications, Information Object Definitions (IOD), Data Structure and Semantics, Message Exchange, Media Storage and others – that medical imaging applications can utilize to create, exchange, store and print information objects (images, evidence documents, reports) to facilitate the interoperability of medical imaging equipment regardless of device manufacturer.
Moreover the DICOM Standards have been enhanced with a number of Service Classes for Workflow Management to support and improve clinical processes. Enabling an unobstructed information flow from system to system eliminates the need of redundant and error-prone manual re-capture of data, ensures consistency and integrity of patient data and allows the medical staff to focus on the tasks at hand rather than dealing with the intricacy of disparate devices and IT systems.
The DICOM Service Classes for Workflow Management provide capabilities to sustain and optimize several tasks associated with the diagnosis and treatment process: data entry, procedure scheduling, image acquisition, post- processing, import of patient data from other facilities, reporting and billing.
April 8-10, 2008
DICOM International Conference & Seminar

4. The Acquisition Workflow
Sustain & Optimize Process Tasks in the Radiology / Imaging Department
Data Entry
Procedure Scheduling
Image Acquisition
Procedure Tracking
Image Storage Management
Unobstructed Information Flow “Assembling the Puzzle”
Key DICOM Services for Acquisition Workflow Support
Modality Worklist
Modality Performed Procedure Step
Storage with Storage Commitment
Instance Availability Notification
Image
Management
(PACS)
Departmental
Information System
(RIS)
Workflow Management
Registration
Order Entry
Scheduling
Tracking
Modality Worklist 1
Performed Procedure Step 2
Storage & Storage Commitment 3
Instance Availability Notification 4
Acquisition
Modality
A bundle of DICOM Service Classes have been conceived around the image acquisition workflow to ease the integration of imaging equipment (modalities) into the overall clinical process:
Modality Worklist (MWL)
Modality Performed Procedure Step (MPPS)
Storage with Storage Commitment
Instance Availability Notification (IAN)
April 8-10, 2008
DICOM International Conference & Seminar

5. Modality Worklist (MWL)1
Modality Worklist (MWL)
Provide Demographics, Procedure and Schedule Details to the Modality
Modality (SCU) Queries the RIS (SCP)
Query Matching Key Attributes
Date / Time of Procedure
Modality Type (e.g. CT)
Station AE Title (a specific Device)
Patient Name / ID
Accession # (identifies an Imaging Order)
Requested Procedure ID …
Query Examples
Today‘s Worklist
CT Procedures Worklist
CT Room 1 Worklist
John Doe‘s Procedures of a Chest Imaging Order 1a
Departmental
Information System
(RIS)
Results: C-FIND Resp. 1b
Query: C-FIND Req. 1a
Image
Acquisition
Modality
Modality Worklist The DICOM Modality Worklist SOP Class facilitates the communication of information from an order scheduling system such as an RIS (Radiology Information System) to an imaging modality and provides the operator with a list of ready to perform examination tasks already including essential information such as patient data and procedure details. This information is then added to the acquired images ensuring that images are unambiguously associated to the proper patient and pertinent to the requested order for examination. Modalities supporting the DICOM Modality SOP Class automatically gather the information from the scheduling system thus eliminating the need to manually reenter patient and procedure information at the equipment.
April 8-10, 2008
DICOM International Conference & Seminar

6. Modality Worklist (MWL)1
Modality Worklist (MWL) 1b
RIS (SCP) Returns Query Results to Modality (SCU)
Null (No Match)
One or More Worklist Entries
Worklist Entry (Unit of Service) = Scheduled Procedure Step (SPS)
Query Return Key Attributes
Patient Data
Name, ID, Demographics
Allergies, Special Conditions
Scheduling Information
Date / Time
Procedure Information
Description, Protocol Codes
Contrast & Medication Administration
Order Information
Accession #, Study UID
Requesting Physician
...
Departmental
Information System
(RIS)
Results: C-FIND Resp. 1b
Query: C-FIND Req. 1a
Image
Acquisition
Modality
April 8-10, 2008
DICOM International Conference & Seminar

7. Modality Worklist (MWL)1
Modality Worklist (MWL)
Deployment of the Modality Worklist Service
Modalities Query & Receive Worklists from RIS
Modality Displays Worklist to Operator
Operator Selects a Worklist Entry (SPS) to Perform
Acquisition of Images (Based on SPS Details)
Insert Patient & Procedure Data into the Image Header
Benefits of Using the Modality Worklist
Eliminate Redundant Data Capture
Avoid Error-Prone Manual Tasks
Facilitate Data Consistency: Unambiguous Association of Images to Proper Patient / Procedure 1a 1b
Departmental
Information System
(RIS)
Results: C-FIND Resp. 1b
Query: C-FIND Req. 1a
Image
Acquisition
Modality
April 8-10, 2008
DICOM International Conference & Seminar

8. Modality Performed Procedure Step (MPPS)2
Modality Performed Procedure Step (MPPS)
Feedback Acquisition Data to Scheduling System (RIS)
Modality (SCU) Sends Acquisition Information to the RIS (SCP)
Tracking of Modality Procedure Status
IN PROGRESS: MPPS N-CREATE
COMPLETED: MPPS N-SET
DISCONTINUED: MPPS N-SET (incl. Reason for Discontinuation)
Logging of Procedure Related Data
Identification Attributes:
Accession #
SPS ID
Patient Name / ID / Demographics
...
List (Series) of Images
Protocol Codes for the Actually Performed Acquisition
Materials Used (Chemicals, Supplies)
Radiation Dose Exposure Values 2a 2b
Departmental
Information System
(RIS)
Image
Acquisition
Modality
MPPS COMPLETED: N-CREATE 2b 2a
MPPS IN PROGRESS: N-SET
Modality Performed Procedure Step The DICOM Modality Performed Procedure Step SOP Class closes the information loop between the scheduling system and the equipment performing the procedure. The status of the requested procedures – scheduled, in progress, completed, cancelled – can be closely monitored to facilitate performance statistics and to derive provisions for improvements of the imaging department’s efficiency. Notification of completion of procedures can be used by scheduling systems to initiate preparations for follow-up actions such as post- processing or reporting. Also details of the effectively performed procedure – the particular examination type, number of images, materials used – is essential input for charging of medical services.
April 8-10, 2008
DICOM International Conference & Seminar

9. Modality Performed Procedure Step (MPPS)2
Modality Performed Procedure Step (MPPS)
MPPS Use Cases (according to IHE)
Benefits of Using MPPS
Keeping Schedules Up-to-date
Better Management of Resources
Gather Information Required for Billing
Trigger for Subsequent Processes: Post-Processing, Reporting
SPS
PPS
results in 1
Simple Case
Unscheduled Case
SPS
PPS
results in 1
Departmental
Information System
(RIS)
Modality Worklist 1
Performed Procedure Step 2
Image
Acquisition
Modality
Append Case
SPS
PPS
results in 1
PPS*
*appended
Group Case
SPS
PPS
results in 1
April 8-10, 2008
DICOM International Conference & Seminar

10. Storage with Storage Commitment3
Storage with Storage Commitment
Secure Ownership and Safekeeping of Clinical Results
Modality (SCU) Requests Storage Commitment from PACS (SCP)
Modality Transmits Images (or other Objects) to PACS:
C-STORE Operations for Images
Modality Issues Storage Commitment Request to PACS:
N-ACTION including List of Instances to Retain
PACS Notifies Modality of Success (or Failure) :
N-EVENT-REPORT
Image
Management
(PACS)
Acquisition
Modality 3b
Request Storage Commitment: N-ACTION 3c
Confirm Storage Commitment: N-EVENT-REPORT 3a
Transfer Images: C-STORE 3a 3b
Storage Commitment The DICOM Storage Commitment SOP Class provides the means to reliably transfer information objects for safekeeping for example from the imaging modality to an image management system such as PACS. Once the receiving system has acknowledged that images have been safely stored, the imaging modality can remove the images from local storage and re-use the available space for images from exams to follow. With such a mechanism in place loss of images can be effectively prevented, an important factor for patient safety and reduction of radiation exposure. Furthermore medical staff can be relieved from the burden of having to double-check or manually confirm the safe storage of images. 3c
April 8-10, 2008
DICOM International Conference & Seminar

11. Storage with Storage Commitment3
Storage with Storage Commitment
Benefits of Using Storage Commitment
Confidence in a Dependable Storage of Clinical Evidence
Eliminate Double-Check / Manual Confirmation Time
Avoid Loss of Clinical Information due to
Network Troubles
Storage Breakdowns
Avoid Unnecessary Re-Examinations (Reduce Radiation Exposure)
Modality can Remove Images from Local Storage and Re-Use Available Space for Exams to Follow
Image
Management
(PACS)
Acquisition
Modality 3b
Request Storage Commitment: N-ACTION 3c
Confirm Storage Commitment: N-EVENT-REPORT 3a
Transfer Images: C-STORE
April 8-10, 2008
DICOM International Conference & Seminar

12. Instance Availability Notification (IAN)4
Instance Availability Notification (IAN)
Inform about Availability of Image Data
PACS (SCU) Notifies the RIS (SCP) that Images are Available for Retrieval & Use
List of Instances (Images)
Location (Retrieve SCP) of Images
Availability Status
Online
Nearline
OffLine
Unavailable
Use of IAN to Initiate Subsequent Processes
Post-Processing
Interpretation / Reporting
Distribution of Images to Other Locations 4
Image
Management
(PACS)
Departmental
Information System
(RIS)
Instance Availability Notification: N-CREATE 4
Instance Availability Notification The DICOM Instance Availability Notification SOP Class can be used by an information object receiver such as an image management system (PACS) to inform other systems such as scheduling systems or workflow management systems (typically an RIS) of the arrival and availability of information objects. This allows for timely preparations of consecutive tasks (post-processing, reporting, patient discharge or transfer) and for book-keeping of images such as storage location and availability (on-line, near-line, off-line, unavailable).
April 8-10, 2008
DICOM International Conference & Seminar

13. Instance Availability Notification (IAN)4
Instance Availability Notification (IAN)
Benefits of Using Instance Availability Notification
In-Time Notification Avoids Excessive Queries for the Whereabouts of Images
Completion of Acquisition Workflow: Ready-to-Use Results
Enable Transition to the Next Process Steps of the Imaging Workflow
Allow for Timely Preparations of Tasks & Resource Allocation for
Additional Procedures
Post-Processing
Reporting
Patient Transfer / Discharge
Image
Management
(PACS)
Departmental
Information System
(RIS)
Instance Availability Notification: N-CREATE 4
April 8-10, 2008
DICOM International Conference & Seminar

14. Integrating the Healthcare Enterprise
Forum (Organization) for Advancing Integration in Clinical Practice
Interoperability Frameworks for Implementing and Deploying Standards-Based (HL7 & DICOM) Integrated Solutions
IHE Integration Profiles
Interoperability Building Blocks to Solve Specific Integration Issues: e.g. Workflows
Packages of DICOM / HL7 Services: e.g. Scheduled (Acquisition) Workflow (SWF) Integration Profile
Refer to: IHE Radiology Technical Framework Vol. I – Scheduled Workflow (SWF) Integration Profile
IHE Scheduled Workflow (SWF) Integration Profile
– includes Acquisition Workflow Management –
The Integrating the Healthcare Enterprise (IHE) Initiative is a concentrated undertaking of both healthcare providers and industry aimed at advancing integration in clinical practice and fostering communication between vendors of medical Information Technology and has successfully proven that established healthcare IT standards such as DICOM and HL7 are key in achieving these goals.
IHE is working to refine these standards and has published specifications – the IHE Technical Frameworks – to provide the industry with a valuable unambiguous compendium for implementing standards consistently. The IHE Technical Frameworks define a series of interoperability building blocks – the Integration Profiles – that address specific integration aspects including workflows. The IHE Scheduled Workflow Integration Profile is intended to resolve issues surrounding the Acquisition Workflow and is – not surprisingly – comprised of the afore mentioned DICOM Service Classes.
April 8-10, 2008
DICOM International Conference & Seminar

15. Conclusions DICOM Services for Acquisition Workflow Management
Improve Interoperability of Imaging Equipment
Ensure Data Consistency
Facilitate Reliable Data Management
Improve Process Efficiency
Better Quality of Imaging Services
Image
Management
(PACS)
Departmental
Information System
(RIS)
Workflow Management
Registration
Order Entry
Scheduling
Tracking
Modality Worklist 1
Performed Procedure Step 2
Storage & Storage Commitment 3
Instance Availability Notification 4
Acquisition
Modality
The DICOM Service Classes for Management of the Acquisition Workflow along with other similar services for supporting additional workflows such as importing, post-processing and reporting are a significant step forward in elevating interoperability of medical imaging equipment, improving efficiency of clinical process and ultimately contribute to a better quality of healthcare services.
April 8-10, 2008
DICOM International Conference & Seminar

16. Thank you for your attention !
References
Glossary
ADT Admission – Discharge – Transfer
AE Application Entity
DICOM Digital Imaging and Communications in Medicine (
DIS Departmental Information (Management) System
DIMSE DICOM Message Service Element
DIMSE-C DICOM Message Service Element-Composite
DIMSE-N DICOM Message Service Element-Normalized
DSS / OF Departmental System Scheduler / Order Filler
HIS Hospital Information (Management) System
HL7 Health Level Seven (
IHE Integrating the Healthcare Enterprise (
IAN Instance Availability Notification
ID Identifier
IE Information Entity
IOD Information Object Definition
MWL Modality Worklist
MPPS Modality Performed Procedure Step
OP Order Placer
PACS Picture Archiving & Communications System
PIR Patient Information Reconciliation
PPWF Post-Processing Workflow
PPS Performed Procedure Step
RIS Radiology Information (Management) System
RWF Reporting Workflow
SCP Service Class Provider
SCU Service Class User
SOP Service-Object Pair
SPS Scheduled Procedure Step
SWF Scheduled Workflow
UID Unique Identifier
Thank you for your attention !
April 8-10, 2008
DICOM International Conference & Seminar