David E. Avrin

Computers in imaging and health care: Now and in the future

Early picture archiving and communication systems (PACS) were characterized by the use of very expensive hardware devices, cumbersome display stations, duplication of database content, lack of interfaces to other clinical information systems, and immaturity in their understanding of the folder manager concepts and workflow reengineering. They were implemented historically at large academic medical centers by biomedical engineers and imaging informaticists. PACS were nonstandard, home-grown projects with mixed clinical acceptance. However, they clearly showed the great potential for PACS and filmless medical imaging. Filmless radiology is a reality today. The advent of efficient softcopy display of images provides a means for dealing with the ever-increasing number of studies and number of images per study. Computer power has increased, and archival storage cost has decreased to the extent that the economics of PACS is justifiable with respect to film. Network bandwidths have increased to allow large studies of many megabytes to arrive at display stations within seconds of examination completion. PACS vendors have recognized the need for efficient workflow and have built systems with intelligence in the mangement of patient data. Close integration with the hospital information system (HIS)-radiology information system (RIS) is critical for system functionality. Successful implementation of PACS requires integration or interoperation with hospital and radiology information systems. Besides the economic advantages, secure rapid access to all clinical information on patients, including imaging studies, anytime and anywhere, enhances the quality of patient care, although it is difficult to quantify. Medical image management systems are maturing, providing access outside of the radiology department to images and clinical information throughout the hospital or the enterprise via the Internet. Small and medium-sized community hospitals, private practices, and outpatient centers in rural areas will begin realizing the benefits of PACS already realized by the large tertiary care academic medical centers and research institutions. Hand-held devices and the Worldwide Web are going to change the way people communicate and do business. The impact on health care will be huge, including radiology. Computer-aided diagnosis, decision support tools, virtual imaging, and guidance systems will transform our practice as value-added applications utilizing the technologies pushed by PACS development efforts. Outcomes data and the electronic medical record (EMR) will drive our interactions with referring physicians and we expect the radiologist to become the informaticist, a new version of the medical management consultant.

Measuring the Academic Radiologist's Clinical Productivity

RATIONALE AND OBJECTIVES The purpose of this project was to understand better the academic radiologists clinical workload in order to determine faculty staffing requirements more accurately. MATERIALS AND METHODS Surveys performed by the Society of Chairmen of Academic Radiology Departments (SCARD) collected data for radiologists in 20 departments in 1996 and 1998; the data included work relative value units (RVUs) per full-time equivalent (FTE). Radiologists in each subspecialty were compared with their counterparts in other departments. The data were collected for each radiologist. Summary statistics showing averages, medians, and quartiles were used to describe workload (in RVUs per FTE) for each department and each subspecialty. RESULTS Overall, the average clinical workload was 4,458 RVU/FTE, with 0.62 RVU per procedure. In those sections for which the faculty performed similar types of procedures across departments, the results were useful. The workload data, however, proved inadequate to compare across subspecialty sections. Between 1996 and 1998, the workload increased from 3,790 to 4,458 RVU/FTE. CONCLUSION The SCARD survey provided very useful clinical workload data, measured in work RVUs per FTE for specific subspecialty sections. At practically all surveyed institutions, increasing clinical workload is competing with academic activities.

Reducing the Rate of Repeat Imaging: Import of Outside Images to PACS

OBJECTIVE Repeat imaging at the transfer of care between institutions is a potential source of overutilization. The purpose of this study was to assess whether importing images obtained at one institution to the PACS at another institution reduces the number of repeat imaging examinations performed, sparing patients unnecessary cost and radiation. MATERIALS AND METHODS Informed consent was waived for this retrospective study, which included 267 patients who had undergone CT or MRI of the abdomen at our or another institution within 4 months before transarterial chemoembolization. Patients were divided into the following four groups based on the availability of their images from institutions other than ours (outside images): outside imaging performed but images not available; outside images available on CD or film but not imported; outside images imported to PACS; and no outside imaging, that is, all imaging performed at our institution. The rates of repeat imaging in the four groups were compared. RESULTS When outside images were not available, 72% (13/18) of patients underwent repeat imaging; when outside images were available but not imported, 52% (14/27); when outside images were imported to PACS, 11% (9/79); and when imaging was performed only at our institution, 13% (18/143). Patients whose outside images were imported were significantly less likely to undergo repeat imaging than were both groups whose outside images were not imported (p < 0.001), and their rate of repeat imaging was similar to that of patients who did not undergo outside imaging (p = 0.79). After adjustment for potential confounders, including age, sex, referring institution, and size and number of lesions, the odds that a patient whose images were imported would undergo repeat imaging were significantly lower than those of a patient whose outside images were not imported (odds ratios, 31 for images not available and 9.0 for images available but not imported; both p < 0.001) and were similar to those of a patient who underwent all imaging at our institution (odds ratio, 0.71; p = 0.51). CONCLUSION Importing outside images to PACS reduces the rate of repeat imaging.

Multimedia in the radiology environment: current concept.

Multimedia has different meanings according to its context. Here, multimedia in the radiology environment is defined as the integration of multiple radiology and medical information systems to facilitate the practice of radiology. These information systems include the hospital information system, radiology information system, picture archiving and communication systems, voice reporting, library information systems, and electronic mail and file systems. The concept of multimedia within the context of integration of these database systems will be presented. An example is given on how to access these information systems by a radiologists desktop personal computer.

Clinician-Educator Pathway for Radiology Residents

Faculty clinician-educator tracks have become increasingly common at US academic medical centers. Although many radiology faculty members belong to such tracks, there is little training in radiology residencies to prepare residents to take on these roles. The authors present a summary of a novel radiology residency clinician-educator pathway developed and piloted at their institution. The key components of the pathway include protected time to work on a substantive education project and a small number of high-quality didactic lectures. Publication or presentation in some form is expected. The pathway includes regular mentorship from highly regarded clinician-educators, as well as didactic training in education techniques and skills. A formal application process was established, as were methods of evaluation during and after the experience.

PACS databases and enrichment of the folder manager concept

Current challenges facing picture archiving and communication systems (PACS) center around database design and functionality. Workflow issues and folder manager concepts such as autorouting, prefetching, hanging protocols, and hierarchical storage management are driven by a properly designed database that ultimately directly impacts the clinical utility of a PACS. The key issues in PACS database design that enable radiologist-friendly, cost-effective, and datasecure systems will be discussed, including database difficulties of the DICOM standard, HIS/RIS/PACS (hospital information system/radiology information system) connectivity, and database issues in data acquisition, data dissemination, and data display.

Development of a dedicated hepatopancreaticobiliary program in a university hospital system

In 2001, a dedicated hepatopancreatobiliary (HPB) cancer program was established at a large, university hospital. Changes included recruitment of specialized HPB faculty, standardization of patient protocols, development of coordinated multidisciplinary research and clinical efforts, collection of prospective surgical outcomes data, and construction of a dedicated cancer hospital. The aim of this study was to evaluate the impact of this program on a university health system including effects on patient volume, surgical volume, outcomes, costs, resident education, and research productivity. Hospital and departmental databases were reviewed for all records pertaining toHPBsurgical cases, diagnosis,and financial information over a 6-year period, including 2 years before (1999-2000) and 4 years after (2001-2004) HPB program development. A more than two-fold increase in the number of distinct patients who had HPB diagnosis was seen across all pertinent departments. A five-fold increase in surgical volume was observed. A multidisciplinary approach to care was implemented, leading to a four-fold increase in sharing of patients across departments. Improvements in operative mortality, hospital contribution margin, resident operative experience, and research productivity were observed. The implementation of a dedicated HPB cancer program with coordinated and standardized research, educational, and clinical efforts had measurable institutional benefit.

Automated examination notification of Emergency Department images in a picture archiving and communication system

This study compares the timeliness of radiology interpretation of Emergency Department (ED) imaging examinations in a picture archiving and communication system (PACS) before and after implementation of an automated paging system for notification of image availability. An alphanumeric pager for each radiology subspecialty (chest, pediatrics, bone, neuroradiology, and body) was used to alert the responsible radiologist that an ED imaging examination is available to be viewed on the PACS. The paging system was programmed to trigger off of the PACS database when an image is received on the appropriate radiology display station. The pager message includes the radiology accession number and examination description (such as chest, two-view, or c-spine, etc). The PACS paging tool performance was assessed by calculating the time elapsed, for each ED imaging examination, from the Time Imaged to the Time of Interpretation, where the Time Imaged is the actual image completion time measured at the imaging modality, and the Time Interpreted is the time a radiology interpretation is rendered to the ED, and is measured from the Radiology-to-ED fax time stamp. These measures were analyzed pre- and post-paging system implementation to determine any impact of the automated notification tool on radiology service turnaround time. Results show an improved radiology response time from image completion to interpretation rendered to ED clinicians, down from hour(s) to minutes, with the automated paging examination notification system. Examinations are read by the appropriate radiology specialty section in a more timely fashion, and fewer cases go unread by radiology.

Continuing quality improvement procedures for a clinical PACS

The University of California at San Francisco (USCF) Department of Radiology currently has a clinically operational picture archiving and communication system (PACS) that is thirty-five percent filmless, with the goal of becoming seventy-five percent filmless within the year. The design and implementation of the clinical PACS has been a collaborative effort between an academic research laboratory and a commercial vendor partner. Images are digitally acquired from three computed radiography (CR) scanners, five computed tomography (CT) scanners, five magnetic resonance (MR) imagers, three digital fluoroscopic rooms, an ultrasound mini-PACS and a nuclear medicine mini-PACS. The DICOM (Digital Imaging and Communications in Medicine) standard communications protocol and image format is adhered to throughout the PACS. Images are archived in hierarchical staged fashion, on a RAID (redundant array of inexpensive disks) and on magneto-optical disk jukeboxes. The clinical PACS uses an object-oriented Oracle SQL (systems query language) database, and interfaces to the Radiology Information System using the HL7 (Health Languages 7) standard. Components are networked using a combination of switched and fast ethernet, and ATM (asynchronous transfer mode), all over fiber optics. The wide area network links six UCSF sites in San Francisco. A combination of high and medium resolution dual-monitor display stations have been placed throughout the Department of Radiology, the Emergency Department (ED) and Intensive Care Units (ICU). A continuing quality improvement (CQI) committee has been formed to facilitate the PACS installation and training, workflow modifications, quality assurance and clinical acceptance. This committee includes radiologists at all levels (resident, fellow, attending), radiology technologists, film library personnel, ED and ICU clinian end-users, and PACS team members. The CQI committee has proved vital in the creation of new management procedures, providing a means for user feedback and education, and contributing to the overall acceptance of, and user satisfaction with the system. Well developed CQI procedures have been essential to the successful clinical operation of the PACS as UCSF Radiology moves toward, a filmless department.

Relevant priors prefetching algorithm performance for a picture archiving and communication system

Proper prefetching of relevant prior examinations from a picture archiving and communication system (PACS) archive, when a patient is scheduled for a new imaging study, and sending the historic images to the display station where the new examination is expected to be routed and subsequently read out, can greatly facilitate interpretation and review, as well as enhance radiology departmental workflow and PACS performance. In practice, it has proven extremely difficult to implement an automatic prefetch as successful as the experienced fileroom clerk. An algorithm based on defined metagroup categories for examination type mnemonics has been designed and implemented as one possible solution to the prefetch problem. The metagroups such as gastrointestinal (GI) tract, abdomen, chest, etc, can represent, in a small number of categories, the several hundreds of examination, types performed by a, typical radiology department. These metagroups can be defined in a table of examination mnemonics that maps a particular mnemonic to a metagroup or groups, and vice versa. This table is used to effect the prefetch rules of relevance. A given examination may relate to several prefetch categories, and preferences are easily configurable for a particular site. The prefetch algorithm metatable was implemented in database structured query language (SQL) using a many-to-many fetch category strategy. Algorithm performance was measured by analyzing the appropriateness of the priors fetched based on the examination type of the current study. Fetched relevant priors, missed relevant priors, fetched priors that were not relevant to the current examination, and priors not fetched that were not relevant were used to calculate sensitivity and specificity for the prefetch method. The time required for real-time requesting of priors not previously prefetched was also measured. The sensitivity of the prefetch algorithm was detarmined to be 98.3% and the specificity 100%. Time required for on-demand requesting of priors was 9.5 minutes on average, although this time varied based on age of the prior examination and on the time of day and database traffic. A prefetch algorithm based on metatable examination mnemonic categories can pull the most appropriate relevant priors, reduce the number of missed relevant priors, and therefore reduce the time involved for the manual task of on-demand requests of priors. Network and database traffic can be reduced as well by decreasing the number of priors selected from the archive and subsequently transmitted to the display stations, through elimination of transactions on examinations not relevant to the current study.