Foreign Exam Management Direct Import- Proposal

1. Proposed Workitem: Foreign Exam Management - Direct Import

• Proposal Editor: Teri Sippel Schmidt
• Proposal Contributors: David Koff, MD
• Editor: Teri Sippel Schmidt
• Contributors: David Koff, MD; Canada Health Infoway
• Domain: Radiology

2. The Problem

A definition: "Foreign Exam Management- Direct Import" (FEM-DI) - Foreign Exam Management Direct Import is the process of taking radiologic studies performed at one site or institution and properly and directly integrating those studies into the "local PACS" at a different site or institution's PACS such that a the studies appear as a proper "prior study" in the same patient folder such that direct comparisons may be made by the radiologist in a timely manner. Note that with FEM-DI there are no CD/DVDs involved (please reference IRWF.b for CD/DVD import).

The clinical problem statement: Over time, patients may receive radiology and/or other studies at many various sites which may or may not be part of the same IDN or "affinity domain". However, these other studies are often "locked away" and inaccessible on a PACS system at a different institution, or even just a different site within the same institution. In other words, radiologic prior studies created at a foreign site should appear seamlessly for the radiologist in the local PACS for participating institutions.

Often, these previous studies, called "priors", have real clinical value. The reading radiologist may change a diagnosis or recommendation based on this historical information.

"The redistribution of medical care into centers of excellence providing centralized specialized care to larger service areas has improved patient outcomes and standardized treatments leading to better patient outcomes. (Stitzenberg et al. 2009) One consequence of this redistribution of care has been the increased flow of patients from peripheral clinics and hospitals to larger tertiary and quaternary care centers with referrals for specialist assessment. " (quoted from SPIE paper)

Today, these prior imaging studies may be shared via:

• patient portals
• web-based viewers
• CD/DVD imports
• other methods

Issues with these methods include login/display time, access issues, direct comparison viewing (e.g., different Patient ID/patient folders), inappropriate hanging protocols (time issue), CD/DVD import issues, inappropriate display tools or hanging protocols, etc. The patient may also be reimaged as a result.

Scope: The current scope would be DICOM study import. (ie., not direct XDS import, although XDS could be an additional transport mechanism in between) Raw JPEG, PDF, etc., are out of scope.

3. Key Use Case

Very common clinical use case:

Dr. X., a radiologist at a busy Cancer Centre, is reporting a large number of CT studies which require comparison to previous imaging often performed at remote sites in the region, mostly community hospitals, but also academic centres where the patient may have been seen. The radiologist has to evaluate changes over time in order to assess treatment efficiency, with previous performed usually 3 to 6 months earlier. There may be a series of previous studies at the same interval over a period of a few years.

Dr. X. needs to report on a lesion’s change in size and appearance, as well as interval development or resolution of other conditions such as metastatic disease, peritoneal seeding or pleural effusions. For accuracy and speed, Dr X has to be able to cross-reference his CT slices and MPRs in DICOM format, using his own measurement tools.

Dr. X. wants the remote CT(s) to be readily available in his patient bag on his own PACS, and the studies displayed using his hanging protocols. He wants the report to be available the same way he displays previous reports for studies performed in his institution.

The last thing Dr. X. wants is to have to access a separate website even if it was to use a single sign-on. He doesn’t want to have to search a separate database, he doesn’t want to wait for images to load as it will slow him down too much through his very busy work day. To make things worse, Dr. X may have to open two separate web interfaces, one for the images, another one for the report, as the DI-r may not be able to move the report with the images.

Instead, and even if all studies are all stored on the regional Diagnostic Imaging Repository, Dr. X. will ask the remote site to print a CD/DVD with the images that he will ask his PACS team to upload in his local PACS to make sure that images are available when he reports the current study. Not only is this a tedious manual process, but it will defer the time the study is reported sometimes up to a few days. And it is not uncommon that the previous report is not available.

Specialty care including referrals, eg., oncology, neurology, etc., are a very common scenario.

Let's discuss an oncology scenario as it may work today between two affiliated institutions/sites:

a.) A patient (PID ON-123) in rural Ontario visits the local referring physician with a question.

b.) The referring physician is suspicious and orders a "CT Abdomen with contrast" at the local hospital.

c.) Unfortunately, the radiologist reading this studies discovers a large, xxx mass.

d.) The patient is immediately referred for surgery to the tertiary care hospital in Toronto.

e.) The "CT Abdomen with contrast" study is written to a DVD and handed to the patient (PID= ON-123). The DVD is delivered by the patient.

f.) The DVD is loaded onto a system in Toronto and reviewed by the oncology surgeon.

g.) The surgery successfully is performed in Toronto on the patient (now known as PID = TO-456).

h.) A follow-up "CT chest/abdomen/pelvis with contrast" study is ordered and performed for patient PID TO-456.

i.) A direct comparison between the prior CT and post-surgery study would be very valuable to and efficient for the radiologist, but the direct comparison cannot be made because the studies are considered to be two different patients (two patient IDs).

A better scenario for two affiliated institutions/sites would be:

a. - d.) remain the same

e. - f.) A DVD is not created, nor given to the patient to transport, nor loaded locally.

g.) Surgery remains the same.

h.) When the follow-up "CT chest/abdomen/pelvis with contrast" is ordered (HL7 v2 ORM), a query is performed to other PACS systems in the affiliated institutions. (leave the multiple PID issues aside as it is addressed in the standards section below, for now, assume it just works)

i.) new - The prior study(-ies) are imported from various PACS systems amongst the affiliated sites. DICOM attributes are "morphed" appropriately such that the study appears on the local PACS with the proper PID and hanging protocols. A direct and efficient comparison may now be made by the radiologist, who has access to all available relevant clinical information.

4. Standards and Systems

Real World Affected Systems (IHE Actor Name):

• PACS (Image Managers/Image Archives)
• RIS/EMRs - an system which creates orders (DSS/OF)
• VNA or DIr (Image Archives)
• probably a new actor - FEM Manager which may or may not be integrated into another real world system (ie., part of the EMR, part of the VNA, or part of a workflow management system)

Standards to be used:

• Existing profiles affected - Although SWF.b, XDS.b-I, MDH-I, and other profiles will be referred to, these profiles would not be directly affected (ie., no changes anticipated to existing profiles) These interactions would be discussed in the Cross Profile Considerations section.

• orders - HL7 v2.x ORM
• image storage - DICOM C-Store to Image Manager

We recommend a discussion of how FHIR and DICOM web services could be integrated in the future, but limit scope to the majority of the real-world installed base (ie., HL7 v2.x and DICOM).

5. Discussion

More background here:

• Investigation into the need for ingesting foreign imaging exams into local systems and evaluation of the design challenges of Foreign Exam Management (FEM); SPIE, Milovanovic, et al
• Canada Health Infoway XDS Implementation Guide - Foreign Exam Management, 2013
• IHE Radiology IRWF.b - for data mappings specifically