Texas Children's Hospital, a definitive care pediatric hospital Iocated in the Texas Medical Center, has been constructing a large-scale picture archival and communications system (PACS) including ultrasound (US), computed tomography (CT), magnetic resonance (MR), and computed radiography (CR). Developing staffing adequate to meet the demands of filmless radiology operations has been a continuous challenge. Overall guidance for the PACS effort is provided by a hospitallevel PACS Committee, a department-level PACS Steering Committee, and an Operations Committee. Operational Subcommittees have been formed to address service-specific implementations, such as the Emergency Center Operations Subcommittee. These committees include membership by those affected by the change, as well as those effecting the change. Initially, personnel resources for PACS were provided through additional duties of existing imaging service personnel. As the PACS effort became more complex, fulltime positions were created, including a PACS Coordinator, a PACS Analyst, anda Digital Imaging Assistant, Each position requires a job description, qualifications, and personnel development plans that are difficult to anticipate in an evolving PACS implementation. These positions have been augmented by temporary full-time assignments, position reclassifications, and cross-training of other imaging personnel. Imaging personnel are assisted by other hospital personnel from Biomedical Engineering and Information Services. UItimately, the PACS staff grows to include all those who must operate the PACS equipment in the normal course of their duties. The effectiveness of the PACS staff is limited by their level of their expertise. This report discusses our methods to obtain training from outside our institution and to develop, conduct, and document standardized in-house training. We describe some of the products of this work, including policies and procedures, clinical competency criteria, PACS inservice topics, and an informal PACS newsletter. As the PACS system software and hardware changes, and as our implementation grows, these products must to be revised and training must be repeated.

As we become increasingly dependent on our picture archiving and communications system (PACS) for the clinical practice of medicine, the demand for improved reliability becomes urgent. Borrowing principles from the discipline of Reliability Engineering, we have identified components of our system that constitute single points of failure and have endeavored to eliminate these through redundant components and manual work-around procedures. To assess the adequacy of our preparations, we have identified a set of plausible events that could interfere with the function of one or more of our PACS components. These events could be as simple as the loss of the network connection to a single component or as broad as the loss of our central data center. We have identified the need to continue to operate during adverse conditions, as well as the requirement to recover rapidly from major disruptions in service. This assessment led us to modify the physical locations of central PACS components within our physical plant. We are also taking advantage of actual disruptive events coincident with a major expansion of our facility to test our recovery procedures. Based on our recognition of the vital nature of our electronic images for patient care, we are now recording electronic images in two copies on disparate media. The image database is critical to both continued operations and recovery. Restoration of the database from periodic tape backups with a 24-hour cycle time may not support our clinical scenario: acquisition modalities have a limited local storage capacity, some of which will not contain the daily workload. Restoration of the database from the archived media is an exceedingly slow process, that will likely not meet our requirement to restore clinical operations without significant delay. Our PACS vendor is working on concurrent image databases that would be capable of nearly immediate switchover and recovery.

T HE CLINICAL EXPERIENCE base for pediatric Computed Radiography (CR) is even more limited than for general radiological practice. The generally small, but widely varying dimensions of pediatric patients, the lack of compliance, and our concerns about undue radiation exposure make these subjects especially challenging. Accommodation of inappropriate technique and postacquisition image processing, should make CR an ideal detector for pediatric examinations. MATERIALS AND METHODSOur hospital has been using CR in our outpatient pediatric care center since October 1995. Our system initially consisted of an AGFA Diagnostic Console Model ADC70, PC-based Patient Identification (ID) Consoles, Sun-based Processing Station and Review Stations, a dedicated laser camera, and a DICOM PACS network including short and long-term archives and an RIS interface. We expanded our use of CR into our main radiology department in August 1997 with two additional CR devices, presently serving our emergency center. RESULTS AND DISCUSSION Changes in PracticeCR demands changes in practice by the technologist, radiologist, and referring physician.1 CR involves changes in capture of the radiographic projection, development of the image, correction of suboptimal images, control of exposure factor, and interpretation of the image. Complicating factors include maintenance, quality control, technologist training, and fitful system maturation. As advocates of the technology, we embraced these challenges along with our partnership with the manufacturer. Performing the ExaminationWith any new technology, documentation and standards lag behind fielding. Poor reliability is characteristic of new hardware models and soft-