Gary S. Norton

Evolution of teleradiology in the defense medical establishment.

The Medical Diagnostic Imaging Support (MDIS) System is a four-year contract to install large-scale picture archival and communications systems (PACS) and teleradiology in Army and Air Force medical treatment facilities. MDIS specifications were based on the results of three years of tri-service research and development through the Digital Imaging Network Systems Project and the Tactical Air Command Teleradiology Project. At the time of the governments request for proposals, MDIS functional specifications represented the most comprehensive understanding of the requirements for large-scale PACS and teleradiology complied by a composite team of radiologists, physicists, clinical engineers, hospital administrators, technologists, and computer systems engineers. As MDIS sites become operational, a better understanding of the capabilities and limitations of teleradiology is emerging. This paper reviews functions and subsystems common to all teleradiology systems, MDIS specifications for teleradiology, installation planning, and the status of Army and Air Force Teleradiology with special emphasis on early installations that validate routine teleradiology operations.

Optimization and quality control of computed radiography

Computed radiography (CR) is a relatively new technique for projection radiography. Few hospitals have CR devices in routine service and only a handful have more than one CR unit. As such, the clinical knowledge base does not yet exist to establish quality control (QC) procedures for CR devices. Without assurance that CR systems are operating within nominal limits, efforts to optimize CR performance are limited in value. A complete CR system includes detector plates that vary in response, cassettes, an electro-optical system for developing the image, computer algorithms for processing the raw image, and a hard copy output device. All of these subsystems are subject to variations in performance that can degrade image quality. Using CR manufacturer documentation, we have defined acceptance protocols for two different Fuji CR devices, the FCR 7000 and the AC1+, and have applied these tests to ten individual machines. We have begun to establish baseline performance measures and to determine measurement frequencies. CR QC is only one component of the overall quality control for totally digital radiology departments.

Objective measures of quality assurance in a computed radiography-based radiology department

Parameters are needed to assess quality assurance in a radiology department where computed radiography (CR) is the principal means of image acquisition. Laser-printed computed radiographs were collected for all patients examined over a period of several days. A sample of 1200 was sorted by subject anatomy and the associated exam information was entered into an EXCEL spreadsheet. Sensitivity (S) numbers were sorted into histogram and analyzed using standard descriptive statistics. Each film was over-read by a board-certified radiologist to assess whether the image was diagnostic and to determine if there were pathologic findings. A significant proportion of images were acquired using inappropriate menu codes. The histogram of S numbers for a given menu code describes a log normal distribution. The S number depends on the technologists ability to control the technique. A significant proportion of the images were deemed non diagnostic, and many correlated to excessive S numbers. Some were a result of mispositioning. The S number is a valid retrospective measure of radiographic quality assurance. Departments using CR should strive for control on menu codes selected and S numbers produced. Such data should be available from PACS databases.

PACS: acceptance test, quality control, warranty, and maintenance continuum

As PACS gain greater acceptance and use in medical facilities the question of life cycle management must be addressed in terms that relate to the common business practices for medical information system and medical devices. The issues in life cycle management of such a system are relatively new to the industry. Increased use of PACS within the medical community requires that standardized life cycle management practices by developed and implemented. This paper develops a new of life cycle issues as cyclic and related events that are not only manageable, but also predictable in terms, of, frequency, duration data content, data exchange, potential outcomes, staffing requirement, documentation, and staff interaction. This view is presented as a continuum that begins at the acceptance testing of a PACS and continues throughout its life cycle. The continuum incorporates the required relationship between quality control testing and maintenance actions during warranty period and the maintenance years. Interrelated cyclic events are described that bind these processes together and provide a basis for long-term proactive management of PACS in a medical environment.

Task allocation chart: quality control of a picture archive and communication system (PACS)

With radiology departments moving into a digital environment, Quality Control (QC) has shifted from film processor monitoring, and film-screen contact tests to computed radiography (CR) calibrations, soft copy display evaluations, and thread test of the imaging chain and the supporting data flow. An analog QC plan encompasses each piece of equipment and everyone in radiology, from the radiologists providing image quality feedback and the technologists performing film processor checks, to the biomedical maintenance technicians calibrating exposure rooms, everyone has input to a good analog QC plan. The digital radiology environment is no different; it requires user and maintainer involvement at all levels. This paper will explain the Task Allocation Chart and how it fits into the QC, warranty, and maintenance continuum that must be in place for an effective installation, implementation, and operation of a PACS.

Medical diagnostic imaging support early experience and efficacy of wide-area intercontinental teleradiology

Intercontinental teleradiology is a newly implemented operational environment for the Medical Diagnostic Imaging Support (MDIS) system project, with phased teleradiology implementation at five sites coming on-line on the Korean peninsula, and four sites being phased in on the island of Oahu, Hawaii, between September 1993 and November 1994. Early implementation and testing efforts began between McConnell Air Force Base, Kansas, and the MDIS Project Office, Fort Detrick, Maryland, in the Summer of 1993. Emphasis is on explaining lessons learned and technical considerations for improving patient care on a global basis. Data on system speed, reliability, image quality, image interpretation and report turn-around is presented. The discussion will cover lessons learned on setting up an intercontinental teleradiology system and various configuration requirements for global teleradiological imaging, diagnosis, and reporting. The scope of the MDIS teleradiology implementation includes U.S. based Picture Archival Communications Systems at major medical treatment facilities which will do consultative and primary diagnostic reading of radiological images sent to them from smaller facilities all over the world.

Benchmark testing of DICOM PACS

The Government released a Request for Proposal (RFP) in January 1997 for a Digital Imaging and Communications in Medicine (DICOM) Picture Archiving and Communication System (PACS) known as the Digital Imaging Network-Picture Archival and Communication System (DIN-PACS). The RFP included the requirement for each of the submitting vendors to support benchmark testing of their proposed architectures. The benchmark test equipment, protocols, and procedures, were developed through a joint effort between the Government, its contracting office, and consulting engineers. The intent of the benchmark test was to evaluate each proposed architecture in nine specific areas. This paper presents the final benchmark test methods used to evaluate a DICOM PACS architecture.

Strategy of DIN-PACS benchmark testing

The Digital Imaging Network -- Picture Archive and Communication System (DIN-PACS) procurement is the Department of Defenses (DoD) effort to bring military medical treatment facilities into the twenty-first century with nearly filmless digital radiology departments. The DIN-PACS procurement is unique from most of the previous PACS acquisitions in that the Request for Proposals (RFP) required extensive benchmark testing prior to contract award. The strategy for benchmark testing was a reflection of the DoDs previous PACS and teleradiology experiences. The DIN-PACS Technical Evaluation Panel (TEP) consisted of DoD and civilian radiology professionals with unique clinical and technical PACS expertise. The TEP considered nine items, key functional requirements to the DIN-PACS acquisition: (1) DICOM Conformance, (2) System Storage and Archive, (3) Workstation Performance, (4) Network Performance, (5) Radiology Information System (RIS) functionality, (6) Hospital Information System (HIS)/RIS Interface, (7) Teleradiology, (8) Quality Control, and (9) System Reliability. The development of a benchmark test to properly evaluate these key requirements would require the TEP to make technical, operational, and functional decisions that had not been part of a previous PACS acquisition. Developing test procedures and scenarios that simulated inputs from radiology modalities and outputs to soft copy workstations, film processors, and film printers would be a major undertaking. The goals of the TEP were to fairly assess each vendors proposed system and to provide an accurate evaluation of each systems capabilities to the source selection authority, so the DoD could purchase a PACS that met the requirements in the RFP.

Teleradiology network to improve patient care in a peacekeeping military operation

The Imaging Science and Information Systems (ISIS) Center of the Department of Radiology at Georgetown University Medical Center recently collaborated with the US Army in developing an off-the-shelf teleradiology network for Operation Joint Endeavor, the peace-keeping mission in Bosnia-Herzegovina. The network is part of Operation Primetime III, a project to deploy advanced communications and medical equipment to provide state-of-the-art medical care to the 20,000 US troops stationed there. The network encompasses three major sites: the 212th Mobile Army Surgical Hospital (MASH) near Tuzla, Bosnia-Herzegovina; the 67th Combat Support Hospital (CSH) in Taszar, Hungary; and the Landstuhl Regional Medical Center (LRMC) in Landstuhl, Germany. Planning for the project began in January 1996, and all three sites were operational by April 1996. Since the system was deployed, computed radiography (CR) has been sued almost exclusively at the MASH and CSH for all general x-ray exams. From mid- May to September 1996, over 2700 CR images were acquired at the MASH and over 1600 at the CSH. Since there was not a radiologist a the MASH, the images were transferred to the CSH for primary diagnosis and archiving. In the same time period, over 550 patient folders were sent from the MASH to the CSH.