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The ultimate radiology workstation |
The annual PACS meeting organized by SIIM and held in
Portland, Oregon from June 28-July 1 was
a major turn-around from past years as
attendance was up, the quality of the presentations significantly improved with
regard to being current and interesting, and vendors getting quite a bit of
traffic in their booths.
The messages were predominantly positive, unlike the doom
and gloom from last year’s “PACS is dead” messages, and many of the sessions
were standing room only, especially those dealing with enterprise imaging and
anything to do with deconstruction of the PACS. SIIM seems to have started to
reinvent itself, albeit slowly. The collaboration with HIMSS, a great
initiative, resulted in publication of several high-quality white papers about
enterprise imaging, which are freely available.
Below are my top ten observations based on attending the presentations
and talking with peers in the industry during the meeting:
1.
Archive-less
PACS - Every year there is yet another acronym introduced that does not
really improve functionality but seems to confuse rather than adds value. Case
in point is the archive-less PACS, which was introduced as a variant between a
traditional Vendor Neutral Archive (VNA) solution and a deconstructed PACS,
however under close inspection, it is nothing more than building a traditional
PACS system using best-of-breed components. It is identical to reconstructing a
PACS from the deconstructed components. SO, nothing new, but what I liked from
the presentation was that it gave a good breakdown of the several PACS
components, being:
·
Order Processing
·
Prior identification/prefetching
·
Modality worklist
·
Image QC
·
Routing
·
Reading worklist
·
Diagnostic display
·
Dictation/VR integration
·
3-D integration
·
Annotations and Key images
·
Inter- and intra-enterprise communications
·
Non-diagnostic display
·
Archiving
I would have added lifecycle
and/or content management, image management, other communication such as
critical result reporting and discrepancy reporting, and peer reviews but this
list was useful to show that a PACS system is not just about image
communication and archiving.
2.
VNA - Vendor
Neutral Archives (VNA’s) are increasingly being installed and are getting more
mature. Most of them are now implementing IOCM (Imaging Object Change Management),
which is the IHE profile that synchronizes a PACS with the VNA with regard to changes
and updates as well as deletions of the images and related information.
Challenges with deploying a VNA are mainly with the integration of specialties,
especially those who create non-DICOM objects such as PDF’s, JPEG’s, MPEG’s or
other file formats. The traditional radiology and to a lesser degree the
cardiology workflow, where everything is scheduled and ordered and managed on a
procedure level, does not quite fit the other specialties hence these issues
arise. Images are typically managed on an encounter or visit level, identified
with a visit number instead of an Accession Number. Prior to image acquisition,
a modality might need to query an EMR to obtain patient demographics using HL7
messaging instead of having a DICOM modality worklist available. There is definitely
a learning curve involved with implementing this in these other departments
especially with the modified workflow. In addition, there are issues with
regard to the integration of the results, especially for the EMR. For example, ultrasound
images created by an anesthesiologist might not belong in the same place where
the diagnostic ultrasounds are managed and displayed, but, rather as part of
the surgery notes. When deploying these devices for enterprise imaging to
include many different specialties, these kinds of issues will surface, which
is to be expected and part of the learning process.
3.
DIY
migration - Image migration is a fact-of-life as many institutions are at
their second or third generation PACS, which in many cases means changing
vendors. The reasons for changing vendors are typically driven by the need for
increasing or adding different functionality, reliability, service and support
issues, financial considerations, or in many cases the perception that another
PACS vendor will magically solve existing issues that in many cases have nothing
to do with the vendor but everything with how the system is used and managed.
Regardless, migration is a fact of
life. When migrating a PACS archive, which can take months and in many cases
more than a year, it becomes obvious how good your previous PACS was managed.
Orphan images, un-identified studies, and other issues with the DICOM objects
will surface when trying to add these to a new archive. Support for non-image
objects such as Key Images, annotations and presentation states might be
lacking or have limitations. Migrations used to be performed by the new PACS
vendor or specialty companies, however, to save cost, more users are doing it
themselves. One can purchase a software migration controller that queries the
old archive and manages the image transfer potentially fixing DICOM tags or
purchase a VNA that has this capability built in. DIY or Do It Yourself
migration is definitely an option, instead of paying a lot of money to your
PACS vendor or a migration vendor.
4.
Evolution
of middleware - Many PACS systems, including VNA’s, have limited routing
capabilities, lack the capability to change tags to identify the origin (i.e.
institution and/or modality), manage duplicate Accession Numbers or coerce
parameters in the header that impact the workstation hanging protocols such as
the study or series descriptions. Hence the advent of middleware vendors who
can provide these capabilities. Note that most VNA vendors do provide quite a
bit of this functionality as they are used to performing tag morphing to preserve
their image integrity, which can be jeopardized by having multiple PACS as a
source, but most PACS systems do have limited functionality with regard to
changing the image data and/or doing sophisticated routing. The good news is
that there are several vendors that fill this void and provide the middleware
to integrate a PACS with other PACS systems or VNA’s, and provide intelligent
routing and tag morphing.
5.
The
ultimate radiology workstation - The first PACS workstations were designed
to mimic a film alternator, resulting in a row of four to six monitors or even
two rows of four on top of each other. In the early years, these were CRT
monsters, very heavy, and from a PACS administrator’s perspective, a “pain in
the back.” Eventually, these configurations dwindled down to a two-monitor
medical display configuration combined with a color text monitor for worklist
display, looking at ultrasounds, and report creation. The reason for the second
monitor is that radiologists were starting to look at CT and MR in a stack
mode, virtually integrating the 3-D space in their minds by replaying the 2-D
axial slices in a CINE mode. However, there is a need to also look at prior
studies, and, in the case of CT ad MR, different reconstructed views (MPR, 3-D
etc.), which again, asks for additional real estate. The circle has come around
again by adding more and more monitors. This combined with an adjustable table
that allows for a combined sitting/standing workplace and an acoustic work
environment that provides a noise-free background, the work environment of a
radiologist has become much more ergonomically sound. Also note in the
illustration the use of a chair that can rotate and always provide a
perpendicular view to the monitor. More research is needed in this area, but
given the increase of occupational injuries caused by having a fixed,
non-ergonomically designed work environment with multiple monitors might become
a necessity.
6.
FHIR
update - The FHIR standard, which is the protocol that provides a
web-services based interface to healthcare systems such as an EMR, PACS
archive, and other information resources, is coming along well. The problem
with this standard is that it is still very much in a developmental phase, as a
matter of fact, its official term for the latest version is DSTU 3.0, which
means Draft Standard for Trial Use version 3, meaning that it is not finalized
yet. The standard relies also on a set of so-called resources that are
accessible in a standard format which are also not quite finished yet. Lastly,
there are many options in the standard, which makes conformance a challenge, in
addition to the fact that there is the version issue, i.e. is the interface
based on version 3.0 or a predecessor? In the meantime, recommendations and/or
standards including federal guidelines are being defined based on FHIR
requirements. It seems as if FHIR is definitely moving up on the hype curve,
but there is serious concern about the potential “bleeding edge” effect when
there are going to be real-life implementations. So far, there is good feedback
from hackathons and trials, but real-life implementations are still scarce and
support from major vendors still in the works or in beta. It might make sense
as a user to have a wait-and-see attitude about early implementations.
7.
DICOMWeb
- The DICOM protocol has not changed since its initial definition in the
early 1990’s. It does not have to, as it is robust and has a large installed
base, as pretty much every medical imaging device supports it. There are many
toolkits that allow for an effective and easy implementation supported by
various operating systems and computers. However, the protocol is not that
efficient for exchanging information over the web, i.e. to be displayed in
browsers and mobile devices, which is getting increasingly important with the
requirement to display images in an EMR. Therefore, similar to the HL7 standard,
which added a web-based version called FHIR, the DICOM standard has added
several options to allow use of web services, generally called DICOMWeb. The
first generation called WADO (Web Access to DICOM Objects) has been around for
quite some time, which basically is a http call for a DICOM image, the second
generation added queries (QIDO-Query based on ID for DICOM Objects) and store
(STOW-Store Over the Web). One should realize that these additions only impact
the protocol, i.e. how the data is exchanged, and not the data formats, including
the header definition. Also, one should realize that these additions are for an
initial relatively small set of applications related to mobile access and most
likely EMR functionality. It is generally understood that the vast majority of
DICOM applications, especially the connection of the digital modalities such as
the CT, MR. etc. will still be using the conventional, robust and proven
protocol. DICOMWeb implementations are also in the prototype phase.
8.
XDS -
Cross-Enterprise Document (and image) Sharing is a set of profiles defined by
IHE to exchange documents and images. There has been widespread implementation
in the UK, however, in the US it has been piecemeal, even though most PACS and
VNA vendors support it. The standard is relatively mature. There were some initial
issues around the definition of the metadata that has to be submitted with the
information to be exchanged, as the identifiers used to manage information
within a department (e.g. Accession Numbers) and enterprise (Patient ID’s) are
not sufficient to identify an image or document uniquely among different
domains. Information such as specialty. and patient cross-referencing is
necessary. The good news is that in the US there are modalities to start doing
XDS document submissions, mainly of non-DICOM objects, such as PDF’s and JPEG’s
to for example a VNA. Interestingly enough the integration of multiple
non-radiology specialties creating these non-DICOM objects might drive a more
widespread adoption of XDS.
9.
Patient
ID reconciliation - As images are being exchanged between multiple
enterprises, there
is a need to reconcile multiple ID’s that are issued by the
various institutions. The US did not implement a universal patient/person
identifier, which was actually part of the initial HIPAA regulations in the
late 90’s due to privacy concerns. But even in countries that have a universal
patient identifier, such as Canada, and many European and Asian countries,
there are always cases where reconciliation is necessary because a person might
not have an ID (think an illegal alien) or does not have his or her ID card
when admitted to a healthcare institution. For example, in Canada, which has a
so-called healthcard with a unique ID, there is still 2 percent of the admitted
population that has incorrect or missing information. To reconcile a patient who
has different local patient ID’s, there are two methods, i.e., deterministic
and probabilistic. The first method assumes a match based on a known relationship
such as a universal patient ID, the second one assigns a weight factor to each
of the items in a list of demographic characteristics such as the name,
birthdate, ID, gender, postal code and phone number and, if the result is
higher than a certain probability threshold, declares a match or mismatch. The
province of Ontario in Canada has currently four regions where information is
shared and has experience with both methodologies. After matching almost 4
million patient records, it determined that .9 percent of the cases using a
deterministic method resulted in an “uncertain match” and .39 percent in a
mismatch. These mismatches were reported back to individual sites to allow for
them to improve their match rate. Bottom line is that with both the deterministic
and probabilistic method, mismatches can still occur requiring QA procedures to
minimize these occurrences.
10.
Pathology
- Digital pathology is very challenging and its implementation is trailing
behind successful implementations in Europe. The main reason is that there is
no FDA approval (yet) for this application requiring institutions to do dual
interpretation, i.e. needing to perform a diagnosis based on the physical slide
as well. There is a DICOM standard defined to encode these types of images that
are created by a scanner, however, support is rare if non-existent. Even if
approved, there are major implementation challenges based on the huge size of
these exams and subsequent demand on infrastructure, archiving, and image
display and manipulation. FDA approval is an initial and necessary step, but
there are many other issues, including workflow challenges and initial
resistance from the pathologists who have to get used to looking at these
images on a monitor instead of through a microscope. Even though there are a
few institutions starting to implement digital pathology, widespread adoption
in the US is still several years down the road.
In conclusion, SIIM2016 was a good meeting. There were good
discussions, and it provided a good opportunity to get up-to-date on new
developments and talk with many users and vendors in a more relaxed and less
crazy environment than the major big trade shows such as RSNA and HIMSS.
Hopefully SIIM will proceed on their current path and next year in Pittsburg
will be as good or better as this year in Portland.