The previous sections outline specific IT consolidation projects that have been implemented, and the benefits derived from such a consolidation are enumerated. Nevertheless, considerable additional effort is required.
Growth in Image Accumulation Rate
At MSKCC, the image accumulation rate has grown as shown in Fig. .
Growth of the image accumulation rate. BAIC is a new imaging facility
Growth of image volume has triggered two major difficulties. One is the time lag until performance enhancements are made across all Radiology systems. Vendor and customer resources required to provide a reasonable level of service for users are exceptionally high when IT systems reach, and even exceed, their performance limit.
Image volume growth has particularly negative consequences at a cancer center, where nearly all exams are read with reference to one or more prior exams. In fact, it can be stated that without image storage consolidation, MSKCC would not have a functioning PACS implementation today, given the image volume growth since 2005, when problems with the prior implementation first appeared.
MSKCC IT Infrastructure
Compounding the problem of application silos is that large enterprises build their own IT infrastructure with the expectation that the applications delivered by vendors will be compatible with the choices the enterprise has made. It is a largely unexplored area, with products being delivered by vendors that at times fail to interoperate with even the most basic technologies that every large enterprise demands for a workable IT environment. Examples are Domain Name System (DNS), Dynamic Host Configuration Protocol (DHCP), Windows domains, Active Directory (AD), etc. A very definitive trend at MSKCC is the expectation that vendors conform to the IT infrastructure already in place, and not deliver incompatible technology that imposes an unacceptable burden on support staff.
Data Exchange Standards
The workflow as shown in Fig. requires exchange of data among applications, an essential component of the IT installation that is associated with very high cost.
Typical enterprise workflow with two standard interface protocols, multiple proprietary data interfaces, and eight proprietary database schemata
Each data interface is accompanied by a capital acquisition, expensive professional services during installation, a line item on a service contract, and a surprisingly high demand for customer resources to identify and correct data exchange failures among applications. The MSKCC experience is that repair of an interface design flaw may take as long as 1 year. And, since each application is built independently, complete transmission of clinically important data may not be possible if one or more of the applications severely constrains the amount of data that can be received and forwarded to the next application.
Business continuity is an essential component of a large imaging enterprise, including High Availability as components fail and Disaster Recovery following a major event such as a power failure, degraded network services, data loss, Denial of Service attack, etc. MSKCC has adopted a solution whereby Radiology IT services can be provided by either of two geographically separated data centers. Ongoing services are provided by the primary data center, with failover to the second data center if operations of the primary data center are unrecoverable within a reasonable time period.
Based on the MSKCC experience, providing services for business continuity is considered the most important motivation in reexamining the architecture of the Radiology IT installation. TCO is unacceptable because MSKCC must operate five business continuity solutions, each using a unique technology depending on the application: PACS, RIS, diagnostic reporting, Nuclear Medicine mini-PACS, and image storage services. Periodic failover testing has shown that for some systems the failover procedures are very complex, in particular for systems that were not designed to accommodate failover to a remote data center. PACS, RIS, and diagnostic reporting are obvious candidates for a single business continuity solution with an efficient failover procedure, resulting in substantial reduction of TCO.
Research on Infrastructure and Applications Consolidation
While the positive aspects of application and systems consolidation have been emphasized in previous sections using three MSKCC consolidation projects, any development that transforms Radiology IT toward a future architecture must take into account and find solutions for some predictable potential problems. For example, data consolidation raises three key issues: (1) demanding too much information, (2) no effective versioning strategy, and (3) no support for system-level extension [11
Operating systems is another key obstacle. The IT industry has the choice of making the very large investment for Windows/Linux interoperability or a simply deciding that a particular installation will use only one of these two platforms. This conclusion is simply the result of repeatedly observing that specific desired functionality works well when implemented within one technology platform, but cannot be made to work at all when interoperability between two different technology platforms is required. And this conclusion applies even if highly skilled engineers tackle interoperability failures.
RIS and PACS
The most significant benefit for Radiology IT can be achieved by a consolidation of the RIS and PACS applications. The RIS and PACS databases contain a substantial number of data instances that are identical, resulting in wasteful duplication of data sets. Departmental workflow is less than ideal, since the progression from order entry to report delivery must cross the boundary between RIS and PACS. It is worth mentioning that awareness of this problem should not be surprising. The initial implementation of MSKCC PACS, first conceived in the early 1990s, included basic RIS functionality.
Additional insight can be gained by examining the work started by the early visionaries designing PACS [7
] and later expanded upon by others [13
]. Radiology IT will never solve the 80% (support)/20% (new initiatives) problem until RIS and PACS are merged into one application. This opinion is not meant to ignore the fact that consolidation of databases with radically different schemata as incorporated in RIS and PACS may present engineers with an intractable problem at the present time.
There are alternatives to the approach taken at MSKCC, for example, a Grid-Based model [15
] leaves the heterogeneous back-end organization intact, while presenting a single data interface for applications. However, researchers involved in such work are cautioned that the problems with the present Radiology IT architecture run far deeper than can possibly be outlined in a single paper. To mention a few of these issues, environments with multiple RIS and PACS [16
] installations add complexity, radiologists demand more extensive and relevant information about patients during interpretation [17
], and sharing PACS among disparate institutions [18
Another option is a Service-Oriented Architecture (SOA). Full scale conversion to SOA requires a major rebuilding of the IT infrastructure. Nevertheless, selected services should be considered. For example, communication of information to radiologists during a reading session such as reason for study, clinical history, and allergies is a good candidate for an enterprise service. Such an implementation avoids a data truncation problem as information is passed through multiple systems prior to presentation in the radiologist’s reading application. Already implemented at MSKCC is a service to deliver images for viewing while a clinician is accessing patient information in the Electronic Medical Record (EMR). It is not a true SOA configuration, but it is implemented as a service provided by Radiology IT for integration with the EMR.