Monday, December 14, 2009

PACS AND Hospital Information System(HIS), Radiology Information System(RIS)

One of the most important benefits of a PACS system is the workstation! Image viewing on a workstation is available within seconds of being captured by the PACS server. Because the system recognizes patient information data from RIS and HIS hubs it is easy to bring up images using the patient's medical record number, or name and other connecting data such as their date of birth. Before we talk about how the workstation works within the PACS network we should discuss how the PACS server makes viewing images and information possible at the workstation.
Patient information such as the medical record number, name, date-of-birth, type of study, date of study and the like is entered into the PACS record through a data bridge. The data bridge is also a DICOM compatible device that adheres to DICOM subclass standards. Pre-selected information fields from the hospital information system (HIS) and radiology information system (RIS) servers are preset to populate PACS text data fields. This is coordinated with the generation of new images sent to the PACS server from a base device (CR, CT, MRI, etc). DICOM includes compatibility of HIS and RIS information systems networked to a PACS system. The DICOM standards are structured so that the PACS server will distribute images and information as if it were the primary base installed device that originated the data. DICOM also addresses interface standards between network peripheral devices based on "underlying" technologies such as HL7, V2, and 3, which allows information transfer in bulk using document paradigm.
The new DICOM standards version 3.0 of 1993 included the development and expansion of PACS to interface with medical information systems. This was an inclusive enterprise extending from the 1987 formation of Health Level Seven, Inc (HL7). HL7 is a non profit organization that in 1963 acquired ANSI accredited standing as a developing organization. This cooperative group of over 2,000 members representing over 500 corporations encompassing greater than 90% of the vendors of healthcare information system services.
Hospitals input and store patient data using what is known as a hospital information system (HIS). The hospital information system is a network of computers used to enter and store patient’s personal data, such as their full name, date of birth, social security number, insurance billing information, and the like. It contains highly personal and sensitive patient information and legal documents pertaining to the patient. These documents are specifically privacy protected by Federal legislation such as the Health Insurance Portability Act (HIPAA). The Radiology Information System (RIS) is a sub-network of HIS that uses certain data fields from HIS to compile the radiology exam and procedures requisition. HIS and RIS may use the same or different servers to interface with PACS through what is called a HIS/RIS gateway or PACS broker. The gateway uses Health Level Seven protocol since it is the most shared protocol for HIS/RIS records and supports DICOM standards for managing its synchronization into PACS. The functions of the HIS/RIS gateway includes managing, sorting, archiving, distributing, and translating patient text information into PACS and onto images.
The typical scenario is that the radiology department receives a computer generated request for an x-ray study that was place by a unit secretary. In order to enter the study all pre-selected fields would have been filled, such as the ordering physician, type of study, etc. Pertinent clinical data is taken from the clinical information system (CIS) and HIS patient file, and attached to the request to complete it. The accession number (A1015046) or exam number assigned to each study can be used for easy retrieval from PACS.
The radiology request (above) contains pertinent information as it was retrieved from the RIS/HIS gateway. Data fields are set-up according to the specific criteria of the hospital and billing services as well as the way the radiologist inputs. Because the data is populated from the RIS database the requisition and examination selected from the base device worklist matches. Entry errors are abolished since the technologist selects from a workflow list that edits patient information onto the digital images and into PACS for display at the workstation. The union between DICOM and HL7 is even stronger since the new April 2004 upgrades. Transcribed reports are also entered into PACS as HL7 documents so that they are displayed along with image documents.
The picture to the right demonstrates how the RIS/HIS gateway is used to add text patient information to each radiographic image as they are displayed and archived into PACS. Because this information comes from a universal RIS/HIS server that the technologist selected from a work list, patient information errors are minimized. And when patient information is entered incorrectly it can be changed throughout all of the patient's records image and text data files because of the interconnectivity of HIS & RIS to all patient files. This interconnectivity is the precursor to what will in the near future be a totally electronic patient enterprise file made up of Clinical information Systems (CIS), Hospital information system (HIS), and Radiology Information System (RIS), and emerging laboratory and surgical information systems.

Detailed patient information is not transferred to PACS, only those specific data fields needed to add information to radiographic images, reports, or identify files accessed by the RIS/HIS broker. PACS limited query of RIS/HIS information is in compliance with HIPAA standards for accessing patient information on a need-to-share basis. Detailed patient information enterprise files are currently being developed by researchers as a tool to easily access PACS documents, Hospital Information (HIS), and Clinical Information (CIS) files, and the like as a unit file, to enhance patient care strategies.
The picture to the right demonstrates how images can be displayed on the PACS workstation with the same image and study information as contained on the film. This is because of the cooperative nature of DICOM and HL7 data sharing. The simple workstation seen in the picture is used by technologist and file room clerks to verify images on PACS and to retro print images and reports

References
Smith, R., "The digital effectiveness of CR," Journal of Imaging Technology Management., Available at:http://www.imagingeconomics.com/library/200107-13.asp., 2001. PC Consultant Group, Inc.,

"PACS & RIS, P practical outline," Available at:http://www.pccgroup.com/pacs_in_a_pic.htm 2004. U.Ewert, H. Heidt, "Current Status of

European Radiological Standards for DND, ASNT spring conference ANSD IIW micro symposium," Orlando, Fl. 03/22-03/27, 1999, proceedings p. 171-173

U.Ewert, H. Heidt, "Approach for Standardization of X-ray Film Digitizers and Computed Radiography,"

Spring conference ANSD IIW micro symposium,” Orlando, Fl. 03/22-03/27, 1999, proceedings p. 171-173 Kodak Learning Center., available at:http://www.kodak.com/global/en/health/learningCenter/elearn/pacs/adv_sys_con/course/pa... 2004.

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