Bush__The_Essential_Physics_for_Medical_Imaging - Biomedical ...

serving nuclear medicine, whereas a network segment carrying CT, MRI, and digitalradiographs may require a higher-bandwidth medium such as Fast Ethernet orFDDI.Interfaces to the Radiology InformationInformation SystemSystem and HospitalIt is advantageous to have interfaces between a PACS, the RIS, and the HIS. A RISis used for functions such as ordering and scheduling procedures, maintaining apatient database, transcription, reporting, and bill preparation. The RIS is notalways a separate system-it may be part of the HIS or incorporated in the PACS.Such interfaces can provide worklists of requested studies, thereby providing patientdata to the PACS and reducing the amount of manual data entry. The PACS or RISshould supply the operator's consoles of the imaging devices with worklists ofpatient descriptors to identify each study. Communication among the RIS, theHIS, and the PACS is often implemented using a standard called Health Level 7(HL7) for the electronic exchange of medical information (e.g., administrativeinformation, clinical laboratory data). HL7 to DICOM translation, for instance,provides worklists to the imaging devices from the RIS or HIS patient database.Using patient identifying information supplied by the RIS or HIS reduces acommon problem in PACS-the inadvertent assignment of different patient identifiersto studies of a specific patient. This can arise from errors in manual dataentry, such as incorrect entering of a Social Security number by a technologist orclerk. Entering a patient's name in different formats-such as Samuel L. Jones, S.L. Jones, and Jones, Samuel-also may cause problems. These problems are largelyobviated if the technologists must select only patient identifiers from worklists, providedof course that the RIS and/or HIS furnishes unique patient identifiers.These worklists also permit prefetching of relevant previous studies for comparisonby interpreting physicians. The network interfaces to the RIS and HIS can providethe interpreting physicians with interpretations of previous studies and the electronicpatient record via the PACS workstation, saving the time that would be required toobtain this information on separate computer terminals directly connected to the RISand/or HIS. These interfaces can also permit the PACS to send information to the RISand/or HIS regarding the status of studies (e.g., study completed).Provision of Images and Reports to AttendingOther Health Care ProvidersPhysicians andWWW technology provides a cost-effective means for the distribution of imagesand other data over the HIS to noninterpreting physicians and other health careprofessionals. A web server, interfaced to the PACS, RIS, and HIS, maintains informationabout patient demographics, reports, and images. Data is sent from thePACS, typically in a study summary form (i.e., the full image data set is reduced toonly those images that are pertinent to a diagnosis). The full image set may be availableas well. The server provides full connectivity to the PACS database to allowqueries and retrieval of information when requested. Physicians obtain these imagesand reports from the web server using workstations with commercial web browsers.A major advantage to using WWW technology is that the workstations need not be