Ultrasonography and PACS

Expectations and problems related to picture archiving and communication systems handling of ultrasound images are discussed. Sonography has peculiarities that must be considered when its integration with picture archiving and communication systems is planned, namely: (1) data volume is about 3 Mb per ultrasound examination and is usually lower than that of other imaging modalities; this makes many requirements less strict; (2) color images represent further problems which can however be solved with systems capable of performing the analog-to-digital conversion in more than 8 bits; (3) the available equipment comes with/without digital ports; the interfaces between the ultrasound unit picture archiving and communication systems are usually based on frame grabbing which might be sufficient for sonography; (4) equipment may be located in different departments or in private offices. Therefore solutions (mini-PACS limited to ultrasound, sub-PACS with a modular development, global PACS) are closely related to the environment. Our personal experience began with the installation of a commercial system 10 years ago. With respect to sonography, picture archiving and communication systems allowed a more reliable and quicker retrieval of previous examinations, the immediate availability of images in different sites throughout the hospital and to avoid filming. About 70000 ultrasound examinations have been archived on optical disks, with a mean of ten images per investigation. Since November 1991, the picture archiving and communication system has been the only archive where such images can be found. The location of workstations in the wards allows the almost real-time availability of images and the immediate availability of reports right after typing. A questionnaire was given to all the hospital's clinicians and the following advantages were pointed out: no examination repetition, no unnecessary investigations, shortening of hospitalization time, impact on treatment choices. Our experience is going on with a new project, DPACS, providing all the services of the former system and offering a full integration with RIS both in the hospital and in the city areas and allowing communication between DICOM and non-DICOM compliant devices.