If your Radiology or Cardiology PACS is at least two years old, you’re probably running out of on-line storage capacity. A more strategic approach to expanding the PACS on-line storage capacity is to deploy a completely separate storage solution, rather than simply adding more media to the storage solution that came with the PACS. The right standalone Storage Subsystem could be the seed that grows into a PACS-Neutral Enterprise Archive.
In the two or more years since your existing PACS was installed, advances in CT and MR imaging have produced larger and larger data sets. The addition of Full Field Digital Mammography has also added a large volume of digital image data to the PACS. Echo and Cath Lab runs are also growing in data volume. It is easy to understand how the amount of on-line storage you originally projected for the PACS can no longer meet today’s actual storage requirements.
Up until a few years ago it was a common practice to configure a Radiology or Cardiology PACS with sufficient on-line storage media to manage the most recent 18 to 24 months of study data and install a Hierarchical Storage Management system to support near-line media in a jukebox, for example a digital tape library. The near-line library has nearly unlimited expansion capabilities if it is linked to a shelf storage repository. While this approach creates a sense of unlimited storage capacity, the practicality of the near-line library is limited by cartridge access rates and the manual loading and unloading of the tape cartridges. All of this activity results in delays in image access. After a few years of experience with the work flow associated with tape management, it is clear why the better solution is the expansion of the on-line storage solution.
Even if the Radiology PACS was configured with an all-spinning storage solution, the volume of storage required two or more years later has probably been underestimated. Whether the PACS is configured with a single or multiple tier storage solution, a storage upgrade is probably inevitable. The question is, “What is the most strategic upgrade solution?”.
Adding additional media (drives), especially of the same type to the existing storage solution may not be the best solution. In the last two or more years, the storage media technology has changed dramatically. If the existing storage solution is approaching five years in age, it should probably be replaced, not expanded. A completely new storage solution based on the latest technology would represent the best value, the most capacity per dollar invested.
Of course this type of upgrade, total replacement of the existing storage solution with a current generation storage solution with three to four times the capacity for the same dollars, will require a media to media data migration. This type of data migration is not the onerous DICOM data migration that is required when one changes PACS, and that is the point! A simple media to media migration moves all of the study data over to a new storage solution, preserving all of the ID errors, and retaining all of the DICOM idiosyncrasies of the existing PACS. In my opinion, this could be viewed as a wasted opportunity.
The need for a storage expansion should be viewed as an opportunity to upgrade the storage technology AND normalize the image data format.
There are numerous arguments in favor of creating a PACS-Neutral Enterprise Archive: [1] Consolidation of multiple department PACS storage requirements into a single centrally administered storage solution, [2] Elimination of the cost of future DICOM data migrations, [3] Provision of data Acquisition and Management resources for imaging departments that have no PACS resources, and [4] Creation of a consolidated data repository for the Electronic Medical Record, accessible through the Physician Portal, viewable by a UniViewer display application. The most significant problem limiting the deployment of this Enterprise Archive is the initial expense.
The same problem limited the early development of the Radiology PACS market. Full-featured PACS was pretty expensive back in those days. What finally got the PACS market going, what put the market on the upswing of the technology adoption curve was the invention of baby steps in the form of Teleradiology Systems and mini-PACS, individual systems that addressed individual needs that might be upgraded expanded or assimilated in to the larger more encompassing PACS that is commonplace today.
The emerging PACS-Neutral Enterprise Archive market needs a baby step, a “starter kit”, a “mini-PACS”. I suggest that that starter kit could be a PACS-Neutral Storage Expansion subsystem for an existing PACS. In my next post, I’ll attempt to describe what I mean by a Neutral Storage Expansion subsystem, and why I believe that such a system is the right strategic move for any organization facing the need to expand their image storage.