2.1 Background
National Taiwan University Hospital (NTUH) was established in 1895. It is a large scale healthcare center and has been operating over hundred years. NTUH has about 2,200 beds for Inpatient services and serves about 7,000 Outpatient daily in average.
In order to deal with the such huge affairs every day, NTUH designs Healthcare Information System (HIS) to cope with the daily work of hospital, HIS has over 30 major independent systems. These systems consist of clinical information applications focused at patient care, pharmacy systems, laboratory systems, radiology systems, administrative systems, financial systems, resource management, etc.
Medical Image Maintenance System is of course one of them.
NTUH in the early stage use the paper medical record to record the patient situation, such the way is not only difficult to store but also spending a lot of time to find the patient relevant medical records. And the medical record often requires the image to record together, doctors will do direct editing of these images but these images are usually only one if the image be used broken. We have to wait a period of time for images to be generated. It is often wasted a lot of time. These images are easily fade and deform so preservation of the environment too wet or dry
will shorten the life of the paper medical records. Therefore, it is very difficult to properly preserve these paper medical records.
Based on the above various reasons, I design Medical Image Maintenance System used in the HIS system at NTUH, it enables the medical image record can be electronicalize, it will do not have the issue of the preservation of the paper medical image record and doctors can quickly query the patient relevant medical image records, do not need to manually to find relevant information of patients to increase the efficiency of the implementation of NTUH. And doctors can repeat to edit the image; the image no longer has the problem of broken.
Therefore, Medical Image Maintenance System reduces the traditional medical image file storage cost required for a large number of economic and space costs. Also, it enhances the work efficiency.
2.2 HIS System
Figure 2.1 HIS architecture overview
The overview of HIS framework those individual components
requirement analysis, HIS choose 4
Service-Oriented Architecture (SOA) as Healthcare Information System (HIS) developing and deploying platform.
For user friendly browsing interfaces,
The Portal Servers and the Web User Interface (WebUI) Servers are
ystem Overview
Figure 2.1 HIS architecture overview
The overview of HIS framework is depicted in Figure 2.1. In the diagram, components are described as the followings.
requirement analysis, HIS choose 4-tiers infrastructure
Oriented Architecture (SOA) as Healthcare Information System and deploying platform.
or user friendly browsing interfaces, HIS adopts web based services.
The Portal Servers and the Web User Interface (WebUI) Servers are the diagram, are described as the followings. By infrastructure and Oriented Architecture (SOA) as Healthcare Information System
web based services.
The Portal Servers and the Web User Interface (WebUI) Servers are Web
Servers.
The Portal Servers support the login process with the Single Sign on Service (SSOS) features. The servers construct dynamic web URL linkages, direct to HIS components in the architecture. To enable the SSOS features, the authentication and authorization Web Service (Auth-WS) is introduced. During the HIS operations, any validation needs to be verified through the Auth-WS. The Auth-WS integrates the Web-session Servers and Win-session Servers.
The Web-session Servers interact with all other servers in the architecture under the .NET Web Services environment. The Win-session Servers are implemented as daemons (Window Services).
All established conversations, sessions are executed by the daemons including database access.
The Web User Interface (WebUI) Servers generate web-based pages for users’ interactive activities. The State-session Servers store the user’s web session status variables for analyzing user logic and validation.
Furthermore, the ancillary Sub-systems provide the connectivity between the WebUI Servers and HIS database (HIS DB) for HIS applications. The messages communicated between the Sub-systems and WebUI Servers are exchanged via the HL7 Framework.
The HL7 Framework is the Middleware Integration Engine of the HIS architecture. It supports message management, routing, mapping, and
database access. Detailed information about the processing of each message is also automatically logged by the Engine. Moreover, the Engine glues the medical systems (or applications) together. The HL7 Middleware accesses HL7 message, embedded in XML format, over Simple Object Access Protocol (SOAP).
In order to achieve the data consistency, we introduce a Data Exchange Server that only receives the message sending from the HL7 Middleware.
While Data Exchange server receiving messages, it will perform the data synchronization among patient demographic data in HIS, patient radiology information orders to Outsourcing Systems, i.e., RIS (Radiology Information System) database, or laboratory orders to LIS (Laboratory Information System), i.e. Legacy HIS, database. This data exchange processing can ensure all data in systems, i.e., HIS and Outsourcing Systems, are updated and consistent.
To increase the performance of the NTUH HIS, a cluster of identical servers are deployed and dispatched dynamically by introducing Layer 4 Switches and Layer 2 Switches. All the servers are configured running under load balancing as well as failover modes to ensure the system’s availability and concurrency. The firewalls are also installed to enhance the security of the architecture.