Download Demonstration of Hospital Wide Image Workstation Network System

Demonstration of
Dept. of Veterans Affairs
Hospital Wide Image Workstation Network System
Ruth Dayhoff, M.D., Daniel L. Maloney, M.S.E.E.
Peter M. Kuzmak, M.S.B.M.E., Barclay M. Shepard, M.D.
Washington VA Information Systems Center
50 Irving Street NW
Washington DC 20422
(202) 745-8305
Overview of Demonstration
To support its physicians in providing high quality
health care, the U.S. Department of Veterans Affairs
is installing and evaluating a distributed system that
provides image management and communications
functionality as an integral part of its existing
integrated hospital information system. The network
provides connectivity for multiple image servers,
80386-based high resolution true color image
workstations, and the networked minicomputer-based
DHCP hospital information system. Medical images
handled by the system include images resulting from
cardiology studies, microscopic pathology slide
views, radiology studies, dermatologic or
ophthalmologic examinations, nuclear medicine
scans, and endoscopic exams.
Overview of Distributed System Hardware
To meet physicians needs for comprehensive
automated multimedia patient data including text and
image data, the VA is developing a distributed DHCP
imaging system that consists of color image
workstations connected to image file servers and
patient alphanumeric data servers across a high
speed fiber optic network (see Figure 1).
The imaging workstation is based on an 80386
microcomputer. A TrueVision VISTA imaging circuit
board allows true color image digitization, capture,
storage and display on an analog RGB monitor.
Image resolution is software controlled and displays
vary up to 1024 x 768 x 32 bits. The image display
memory can hold up to four megabytes of image
data for scrolled display. Input can be from a video
camera, directly from medical instruments, via file
format conversion from instruments, or from scanners
(see Figure 2).
Network
Figure 1: Diagram of Hospital Wide Image Workstation
Network
967
01 95-4210/90/0000/0967$01.00 0 1990 SCAMC, Inc.
architecture also accommodates file transfer protocols
allowing image files to be copied to local hard disk or
remote file server.
The hospital-wide network will be equipped with
optical disk juke box units capable of storing
gigabytes of data on removable media, as well as
magnetic mass storage devices for rapid data access.
The workstation software currently includes an
abbreviated clinical record and full integration of
images with the existing DHCP cardiology/medicine
package and a prototype nuclear medicine package.
Images are fully integrated with the existing application
packages in a manner appropriate to the context of
the application. Images are automatically retrieved
and displayed as the corresponding text data appears
on the screen, without user intervention. A wide
variety of types of images have been included in the
abbreviated clinical record database.
Relevance to Medical Informatics and Medical Care
The VA's Decentralized Hospital Computer Program
(DHCP) is currently in use in virtually all 172 VA
Medical Centers, as well as the Department of
Defense, the Indian Health Service, other federal and
state agencies, and private hospitals in the US and
worldwide. The ability of this widely used public
domain HIS to handle images as well as text is
important in planning for future developments. The
approach used here can be used as a model for other
Figure 2: High resolution true color workstation
diagram
Network Architecture
Workstation communications of both text and
images are currently based on ethernet. To
maximize throughput, the network for the hospitalwide system consists of a fiber optic 100 mbit/sec
backbone with dedicated ethernet interfaces to the
workstations. The network software co-resides in the
workstation as two concurrent protocol stacks for text
and image communication. Patient text data from
the MUMPS-based DHCP system can be shared
directly within the MUMPS environment. Using the
workstation, individual data items can be accessed
transparently on remote data servers using
networking facilities provided by various MUMPS
implementations.
systems.
A number of standalone image-producing medical
instruments are beginning to implement methods for
storing and retrieving images. These image storage
systems are implemented as standalone systems,
rather than as part of an integrated clinical information
A few sites are developing one-way
system.
communication paths between the image system and
their hospital information systems. However, the VA's
project is unique in that:
The workstation contains networking software
(Novell Netware) that allows digital image files
(individual files directly under the operating system)
located on remote disks to appear as files on disks
locally connected to the workstation. Therefore, any
program that can access a file on a local disk can
access that file located on the workstation's virtual
disks without any software changes.
This
transparency of software provides modularity that will
allow flexibility for future modifications.
This
(1)
(2)
(3)
it is attempting integration at a higher level in the
hospital information hierarchy than has been
done before
it is a multi-way communication system
it can handle a wide variety of medical images
reaching beyond radiology
Under the VA design, the system will be capable of
delivering more comprehensive medical data to
physicians than has been possible in the past.
968