Commercial Open Source RIS/PACS:

The ClearCanvas Experience

Norman Young

, Clinton Chau

and John Adziovsky

ClearCanvas Inc., 620-438 Richmond St. W., Toronto, M5V 3S6, Canada

The Joint Department of Medical Imaging, University Health Network, Mount Sinai Hospital

and Women’s College Hospital, 600 University Ave., Toronto, M5G 1X5, Canada

Abstract. ClearCanvas, an open source, healthcare informatics company is

currently developing an open source RIS/PACS for a large Canadian hospital.

The experience thus far has shown that an emphasis on application usability, as

well as professional service and support are necessary for enhancing the

credibility of open source healthcare solutions. Supporting such initiatives

requires a solid business model that can generate the needed revenue. A model

being explored draws on multiple revenue streams, including service contracts

and value added features, from both the founding organization and commercial

members of the ecosystem.

1 Introduction

ClearCanvas is a private, open source, healthcare informatics company based in

Toronto, Canada. Its primary mandate is to develop an industrial strength, open

source RIS/PACS (Radiology Information System/Picture Archiving and

Communication System) solution for The Joint Department of Medical Imaging

(JDMI), University Health Network, Mount Sinai Hospital, Women’s College

Hospital. JDMI is one of the largest medical imaging departments in Canada, with an

annual volume of over 600,000 studies. The RIS/PACS consists of three main

components:

• The PACS viewer allows DICOM (Digital Imaging and Communications in

Medicine) images to be viewed by radiologists, referring physicians and

other image consumers.

• The PACS server archives imaging studies for long term storage and serves

them up to DICOM clients such as the PACS viewer.

• The RIS manages the entire workflow of the imaging department, from the

point a patient checks in with the receptionist, to when the final report is

issued to the referring physician.

Young N., Chau C. and Adziovsky J. (2009).

Commercial Open Source RIS/PACS: The ClearCanvas Experience.

In Proceedings of the 1st International Workshop on Open Source in European Health Care: The Time is Ripe, pages 22-27

DOI: 10.5220/0001827400220027

 SciTePress

Underlying all three products is a comprehensive application framework and SDK

(software development kit) that allows new functionality to be quickly and easily

added via a plugin mechanism.

2 Tools and Methodology

A combination of open source and commercial, off-the-shelf development tools have

been employed over the course of this project. Because all products are built on

Microsoft's .NET 3.0 platform, the primary development environment used is

Microsoft Visual Studio. In the backend, Microsoft SQL Server serves as the database

management system. Subversion is used for source control, and Trac for ticket and

requirements management. Source code hosting is outsourced to an online service

provider. SourceForge was not chosen for code hosting because it was foreseen that

proprietary code branches would need to be created.

An agile software development methodology known as Scrum has been

successfully employed in the development of all ClearCanvas products. Scrum is a

form of iterative development, where at the beginning of an iteration or “sprint”—

typically one month in length—the customer negotiates with the development team a

set of requirements to be implemented. That backlog of items represents a contract:

the development team agrees to implement all of the items in the backlog and the

customer agrees not to insert any new items during the sprint. At the end of the sprint,

the customer reviews the features implemented and determines whether they have

been done satisfactorily. If not, the “failed” items are fed back into the next sprint.

This methodology of continuously integrating customer feedback into the

development process acknowledges the reality that software requirements often

cannot be known with full specificity at project commencement and in fact, can

continue to change well into the development cycle. This approach enhances the

likelihood that the final product is something the customer is, in fact, happy with.

3 A Unique Relationship

At present, ClearCanvas essentially plays the role of a development consulting firm,

as it has been contracted by JDMI to build a new RIS/PACS. It is important to note,

however, that the relationship with JDMI is, in practice, more than merely

contractual. For example, the entire company is co-located on hospital premises. As

well, members of the hospital staff are integral members of the project team. As

discussed later, this unique partnership has created the conditions necessary for the

development of a system that is highly user-centric.

4 Insights Gained

The project is still very much a work in progress. As such, it is premature to

comment on the efficacy of particular initiatives and strategic decisions. However,

insights gained thus far into what constitutes a commercially sustainable open source

project can be offered.

4.1 Usability is Paramount

Many open source projects begin out of a developer's need for a tool or application of

some kind that does not yet exist. In this scenario, the developer is often also the

user. This is very helpful in enhancing the usability of the application, since the so-

called “eat your own dogfood” dynamic is at work. However, with open source

healthcare applications, this is typically not the case. The user is almost never the

developer. And so, because the developer is not forced to use the software in the way

a user would, ensuring the application's usability is particularly challenging.

This risk has been mitigated in a number of ways. First, project leads have all had

prior experience designing RIS/PACS solutions. Such experience has not only been

informative as to what user interface metaphors work, but also those that do not.

Second, on the RIS project, the project manager is actually a member of the hospital

staff who has had several years of hands-on experience with managing radiology

workflow. Her intimate knowledge of not only the department's overall process, but

also its process idiosyncrasies has been invaluable in helping the development team

design a system that is comprehensive in its features and requirements. Third, the

ClearCanvas office is co-located at JDMI. This enables convenient interaction with

users, and also facilitates the company policy that all employees attend at least one

tour of the clinical areas to understand how users interact with the existing

RIS/PACS. Fourth, the software has been subjected to formal usability testing in the

hospital's own human factors laboratory. This has allowed the project teams to see

how users respond to the applications under controlled conditions, the results of

which are then fed back into the development process.

4.2 Aesthetics Matter

An application's aesthetic appeal is important. Given two functionally equivalent

systems, users are more likely to use and feel better about the more visually attractive

one. As open source applications are sometimes criticized for not being as

“professional” as their commercial counterparts, aesthetics become that much more

important in enhancing their credibility. Attention to aesthetic details comes in many

forms, such as clean and consistent user interfaces, pleasant colour schemes and well-

designed icons.

4.3 Developers are Users Too

Usability is often thought of only from the perspective of the end user. But in an open

source project, developers are users too, though in a different sense. Thought must be

given to how to make it as easy as possible for external developers to participate in

the project, or at the very least, how they can extend the application for their own

purposes. It is not good enough that the code is open source. The code base needs to

be well-organized and easy to navigate. APIs (application programming interfaces)

must be easy to use. The system architecture needs to be well documented so

developers have the “big picture” in mind. Patterns and best practices need to be

employed consistently.

With all these usability elements in mind, significant effort was invested into

developing an application framework and SDK, with the goal of making common

customizations easy, and more obscure customizations possible. The plugin-based

framework provides developers a well-defined and well-understood method of

integrating new functionality into the products without having to be familiar with the

entire code base.

As with any open source project, there is significant variation in the skill level of

the developers who use the SDK. Some are professional developers working for

companies. Others are students and hobbyists. Although the developer

documentation is fairly comprehensive, it has had to be supplemented with explicit

code samples and an online discussion forum in which developers can ask questions.

4.4 Software is Not Enough. Service and Support is Key

The vast majority of hospitals and clinics in the North American healthcare IT

market, especially the smaller ones, have little desire to support their own RIS/PACS.

They want a system where they can call a single number to have problems addressed.

For this reason, simply providing software, even if it is free (in the “free beer” sense)

and open source is insufficient. To the customer, a service contract is tantamount to

an insurance policy for when problems arise. For many, the lack of such support

services automatically disqualifies the software, no matter how good it may be. It is a

risk they simply cannot assume. From a revenue generation perspective, this is good

news for open source healthcare IT companies, as it suggests that customers in fact

want to pay for service and support.

It is worth noting, however, that this view of service contracts may be particular to

developed nations. ClearCanvas’ limited experience with institutions in developing

countries suggests that they tend to be reluctant to pay for service contracts for

financial reasons, and thus are much more willing to support the software themselves.

4.5 Open Source as a Basis for an Ecosystem

In the traditional proprietary software model, knowledge tends to be centralized in

one place: the founding organization. The risks of this approach, such as vendor lock-

in, are well known. In the open source model however, knowledge is decentralized.

This is important, as it allows for people outside the founding organization to become

experts. Such experts are then in a position not only to make code contributions, but

can also go on to provide commercial services and/or other value-added features.

This is essentially an ecosystem, of which both commercial and non-commercial

entities can be a part.

Such an approach is not without precedent. DotNetNuke (DNN), a very successful

open source web based Content Management System (CMS) has a thriving ecosystem

that benefits from both open source and commercial contributions. Entire companies

based on the open source DNN platform have formed, offering everything from

plugins, to website “skins”, to training videos.

ClearCanvas is in the early stages of experimenting with bringing such an approach

to the RIS/PACS domain. One can envision an ecosystem consisting of, for example,

first tier service providers, professional service companies, custom development

shops, etc. However, it is important to realize that RIS/PACS is a highly specialized

market, whereas CM systems such as DNN have general market appeal and are not

sector specific. Expectations need to be tempered by this important difference.

4.6 Open Source as a Platform for Value Added Features

One of the great strengths of DNN is its plugin architecture. It has allowed developers

to extend the functionality of the base platform by making available to the community

a multitude of plugins for a wide range of specialized purposes. What is notable

about the DNN ecosystem is that there are both open source and commercial (closed

source) plugins.

This “mixed source” model, while likely problematic for some open source purists,

may hold the most promise in the RIS/PACS domain. The practical reality is that the

types of vendors who would take advantage of a platform such as that offered by

ClearCanvas, are most likely specialty companies (e.g. advanced visualization,

computer aided diagnosis, etc.) whose competitive advantage depends on being able

to protect their intellectual property through closed source plugins. Releasing

platform software under a viral open source license would likely stifle the growth of a

commercial ecosystem, as vendors would be reluctant to open source their plugin

code. For this reason, ClearCanvas chose to release all of its products under the

permissive New BSD license, so as to encourage plugin development by commercial

vendors. Doing so also allows ClearCanvas to add value to its own commodity

system through specialized commercial plugins for say, speech recognition, enterprise

management, data mining, etc.

This approach can be taken one step further by encouraging plugin vendors to sell

their plugins via e-commerce on the ClearCanvas website. By taking a percentage of

the sales, another revenue stream can be developed. For the vendor, there is

incentive to sell on the ClearCanvas site because the availability of a free RIS/PACS

naturally generates web traffic, thereby increasing sales. Plugin vendors could also

conceivably buy advertising or product information pages on the site to promote their

products. The open source platform then becomes a means to generate revenue.

5 Conclusions

Factors such as usability, aesthetics, developer friendliness and the availability of

service and support are necessary for open source healthcare solutions to gain

acceptance. They are important in part because open source software still has a

credibility problem in the healthcare sector. It is still seen as “unreliable” and “risky”,

both technically, and in terms of how problems are resolved when things go wrong

with a live system. Overcoming this image problem through what essentially amounts

to elevated professionalism has a cost. For this reason, solid business models must

exist. In developed countries, a significant source of revenue can likely be found in

service contracts, as healthcare institutions view them as being essential. If an open

source system is architected effectively, it can also be a platform for revenue

generating, value added features, which can be developed by the founding

organization, or by commercial members of the ecosystem.