One of the most common information systems used in hospitals by clinicians is the picture archiving and communications system (PACS). These systems manage digital images and videos for the hospital or clinic and are needed as these files often have a very high resolution and hence high file size (8,9). To enable a clinician to review a medical image efficiently and from multiple locations in the hospital (and sometimes also at home when on-call), the PACS system must be able to deliver these large files quickly and effectively and offer tools for viewing and manipulating images and generating reports. The PACS system also must be electronically linked to the systems that generate the images such as digital radiography systems, ultrasound machines, and computed tomography (CT) and magnetic resonance imaging (MRI) systems. The PACS system will also link the PAS and any EMR/EHR system within the facility to pull in patient identifiers and demography and show relevant reports alongside images (10). PACS systems are therefore quite complex but the benefits of using digital radiology instead of physical media (film) usually out-weigh the cost and complexity of maintaining PACS systems. This has meant that PACS systems are one of the few information systems used in hospitals that have a clear business case and have made it one of the most widely adopted types of systems in healthcare to date (11,12).
The need for interoperability across the different sources of imaging data and other information systems has driven the need for an information technology standard that is agreed by all manufacturers (of both information systems and medical imaging hardware). The Digital Imaging and Communication in Medicine (DICOM) standard was first published in 1993 and has since been very widely adopted around the world and is now recognised by the International Organisation for Standardisation as ISO 12052 (13,14). The standard is managed by the Medical Imaging and Technology Alliance which is a division of the National Electrical Manufacturers Association who own the copyright of the DICOM publications.
The PACS system is used through the hospital but a different system, the radiology information system (RIS), is used for supporting the information needs of the radiology department. This includes such features as registering patients, facilitating the process of capturing medical images and storing images and communication with PACS and HIS systems.
Paton, C (2024). Textbook of Digital Health.