A hospital-wide distributed PACS based on intranet.

A hospital-wide Picture Archiving and Communication System (PACS) is currently under development at the University Hospital of Geneva. After a first implementation including two oneterabyte optical libraries, the system is expanded to integrate all the imaging modalities of the hospital. The new storage requirement is 10 terabytes to cover three year archive. A large distributed image archive has been designed including new archive servers for long-term storage and display servers for medium-term storage. The acquisition, archive and distribution cycles are performed using separated networks combining Fast Ethernet and Ethernet. Image files are distributed to the wide-hospital using a prefetching strategy or an Intranet server, RADIOLAB. The first mode takes advantage of the fully integrated hospital information system DIOGENE 2 to allow the automatic retrieval of studies in advance. The second mode provides a convivial study selection from any conventional WWW (World Wide Web) browser. Image files are then transmitted to the user's display station using HTTP (HyperText Transfer Protocol) and handled by OSIRIS software, which acts as a helper or viewer. Such a system is expected to meet the time requirement, which is less than three seconds per image.