St. Joseph Health Care in London, Ont., which was the first facility to deploy PACS in the fall of 2004, said its digital diagnostic imaging has become filmless and paperless. When clinicians were previously dealing with film-based medical images, various problems would arise, such as difficulty in tracking down films or films getting lost, which sometimes resulted in having to perform duplicate tests, explained Beattie.

The London Health Sciences Center claimed it has gained a savings of C$1.2 million (US$1.04 million) in film savings alone. By spring of 2005, all eight hospitals have deployed and were online with the Digital Imaging Network project, Beattie said.

PACS consists of a two-tiered storage system, according to Peter Gilbert, IT director for St. Joseph Health Care and London Health Sciences Center. At the top of the architecture is a 10-terabyte-array digital storage system that holds the more recent and relevant images, Gilbert said. The system is based on Hewlett Packard's (HP's) storage area network architecture.

"If an exam is taken within a year, then that image will be sitting in the first-tier storage," said Gilbert. The image is also replicated in the second-tier storage, which uses HP's Medical Archiving (HPMA) system.

The HPMA runs on HP's ProLiant servers with x86 processors and HP StorageWorks Modular Smart Arrays. HPMA has a dual function, said Gilbert. It serves as a backup in the event that the first storage layer becomes unavailable. The HPMA also serves as a long-term cache for older images capable of housing up to 60 terabytes of storage or five years worth of archiving capacity, he added.