Results of and comments on the 2000 survey of the American Association of Academic Chief Residents in Radiology.

RATIONALE AND OBJECTIVES: The American Association of Academic Chief Residents in Radiology (A3CR2) annually surveys radiology residency programs on issues related to training. The objective is to highlight national similarities, differences, and trends to help programs establish standards and improve residency training. MATERIALS AND METHODS: Questionnaires were mailed to 180 accredited diagnostic radiology residency training programs in the United States. The survey covered the usual general topics and more specific topics considered every 4 years; for 2000 the latter were on-call issues and the chief residency year. RESULTS: Completed surveys were returned from 63 programs (35%). Important findings included increased caseload and call commitments, especially for smaller programs. Resident salaries appear to have increased more than the consumer price index. Nonemergent after-hour coverage and teleradiology are now a large part of the resident work practice. Women continue to be underrepresented, with a trend downward. Chief residents are more involved in organizing preparation for board examinations and have greater office facilities and more administrative duties. CONCLUSION: This survey provided useful insights. All levels of residency face increased workloads. On-call hours have not changed, but the work has intensified and the use of teleradiology has increased. Many programs have adopted a "night-float" system, and nonemergent after-hours coverage should be considered in any program evaluation. Continued vigilance and sustained efforts are required to ensure that radiology is considered as a specialty by both men and women. With increased demands on attending physicians' time, chief residents may need to take on more administrative responsibilities.

Detection of CT-proved pulmonary nodules: comparison of selenium-based digital and conventional screen-film chest radiographs.

PURPOSE: To compare hard-copy digital chest radiographs obtained with a selenium-based system with wide-latitude asymmetric screen-film radiographs for detection of pulmonary nodules. MATERIALS AND METHODS: Fifty patients undergoing thoracic computed tomography (CT) for suspected pulmonary nodules were recruited to undergo both digital and screen-film posteroanterior (PA) and lateral chest radiography. Three chest radiologists blinded to the CT results independently reviewed each digital and screen-film radiograph, identified each nodule, and graded their confidence for its presence. RESULTS: Seventy-eight pulmonary nodules (mean diameter, 1.5 cm; range, 0.5-3.5 cm; 62 soft tissue, 16 calcified) were identified with CT in 34 patients, while 16 patients had clear lungs. The mean sensitivity for the detection of all nodules by all readers (PA and lateral) was 66% (95% Cl, 54%, 76%) for digital radiographs and 64% (95% Cl, 52%, 74%) for screen-film radiographs. Differences between the two techniques were not statistically significant (P > .05, Student t test). There was no difference in mean false-positive-true-positive ratios (PA, 0.35; lateral, 0.53) or positive predictive values (PA, 74%; lateral, 65%), and no significant difference (P > .05) was seen in mean reader confidence rating. CONCLUSION: In detecting pulmonary nodules, radiologists perform comparably with selenium-based digital and wide-latitude asymmetric screen-film radiographs.

Chest radiography: depiction of normal anatomy and pathologic structures with selenium-based digital radiography versus conventional screen-film radiography.

PURPOSE: To compare the subjective visibility of normal anatomy and pathologic structures in the chest on conventional screen-film radiographs versus selenium-based digital radiographs. MATERIALS AND METHODS: Screen-film and digital standard posteroanterior (PA) and lateral chest radiographs were obtained in 49 patients (32 men, 17 women; mean age, 60 years; range, 24-91 years) undergoing chest computed tomography (CT). Conventional images were phototimed at 115 kVp with use of a wide-latitude screen-film system and an antiscatter grid. Digital images were obtained at 150 kVp with use of a commercial system with a selenium detector and an air gap alone for scatter reduction. The image sets were independently compared by four radiologists, and the relative visibility of anatomic and pathologic features (proved at CT) was graded. Statistical significance (P < .0028) was evaluated with a one-tailed t test. RESULTS: Visibility with the digital images was statistically significantly increased for 11 of 13 normal anatomic features and for pathologic structures in the lung, soft tissue, and bone. CONCLUSION: Subjective visibility of pathologic structures and most normal anatomic features in the thorax was statistically significantly improved with selenium-based digital chest radiography compared with conventional screen-film chest radiography.

Networks for electronic radiology.

Next-generation health care systems must successfully integrate hospital information, laboratory automation, and medical-image management to provide a seamless view of the complete medical record to the primary care physician across a distributed medical enterprise. Broadband networks are an important component of the systems required to achieve this goal. This article provides a brief tutorial on relevant network principles and products, a perspective on the evolution of the field, and a simple view of the network requirements posed by electronic radiology.

Limited coronal CT: an alternative screening examination for sinonasal inflammatory disease.

Coronal CT is the definitive procedure for radiologic evaluation of sinonasal inflammatory disease, yet many clinicians rely on the less expensive plain film sinus series. We designed a limited four slice coronal CT and prospectively compared it with conventional coronal CT and plain film sinus series in 25 patients to determine whether a limited CT examination is a suitable alternative to these other radiologic procedures in screening for sinonasal inflammatory disease. The presence, amount, and location of mucous membrane disease, opacification, air fluid levels, retention cysts, erosions, and anomalies were recorded for each technique. The limited CT agreed with the complete CT in 82% of the 200 sinus compartments reviewed. Localized disease, usually mucosal thickening of 3 mm or less and missed on the limited CT, but detected on the complete CT, accounted for 22 of 36 errors of interpretation. Underestimation of mucosal disease, usually 2 mm or less, accounted for eight errors and misinterpretation of partial volume effect for three errors. Using complete CT a s the established standard, plain film missed 37 instances of disease detected on the limited CT; 73% involved an error of mucosal thickening 4 mm or greater. A limited coronal CT of the paranasal sinuses offers a potentially lower cost alternative to complete CT in screening for sinonasal inflammatory disease. It is more accurate than plain film series. Localized disease and osteomeatal disease is underestimated with the current protocol, and so a limited CT should not be used for evaluating potential cancer patients or for surgical planning.

New techniques in chest radiography.

Advances in film-screen radiography (e.g., InSight) and beam equalization radiography (e.g., AMBER) have improved the quality of standard chest radiographs. Despite the improved visibility of the mediastinum and retrocardiac and retrodiaphragmatic lung with AMBER, it is debatable whether this advantage outweighs its disadvantages, especially the increased cost of the unit and decreased reliability. The benefits of storage phosphor systems have largely been in the area of bedside radiography, where consistent image quality over a wide range of exposures and image processing compensate for the lower spatial resolution. More routine application of this technology to standard chest radiography is likely, especially as image processing techniques improve and digital units become more cost effective. Storage phosphor digital imaging may be the most appropriate technique for entry of images into a picture archiving and communication system in which images stored in image management systems can be displayed on high-resolution monitors in local or distant sites. Such systems have the potential of improving patient care by providing more rapid access to radiographic images, especially if the image is accompanied by an immediate report. Because of the significant expense of a picture archiving and communication system, their introduction is likely to be gradual, via networks in specific areas such as between intensive care units and radiology departments.

High-resolution computer display of portable, digital, chest radiographs of adults: suitability for primary interpretation.

OBJECTIVE: The suitability of using a high-resolution computer-display system for primary interpretation of adult chest radiographs obtained with portable apparatus and storage phosphor technology was evaluated with receiver operating characteristic analysis and subjective methods. MATERIALS AND METHODS: Sixty portable digital chest radiographs showing abnormalities that approached the resolution limits of our computed radiography system were selected. The original digital data making up the 2140 x 1760 x 10 bit images were transferred to a cathode ray tube (CRT) display system composed of two Megascan monitors. Postprocessing rendered two images, one for each monitor, to emulate the two-on-one hard-copy format produced by the computed radiography system. Each image set was interpreted independently by three radiologists experienced with hard-copy format. Limited level and window adjustments were allowed during CRT interpretation. For both CRT and hard-copy display, images were graded on the basis of the interpreter's confidence in the presence of pneumothorax and parenchymal abnormalities. Three types of foreign devices were subjectively analyzed: endotracheal tubes, nasogastric tubes, and temporary epicardial pacer wires. RESULTS: No significant differences were found in detecting pneumothorax or focal infiltrates. One radiologist found the hard copy better for detecting diffuse infiltrates (p = .02); two radiologists favored CRT for visualizing nasogastric tubes (p < .005, p < .02); and one radiologist favored CRT for visualizing temporary epicardial pacer wires (p = .05). CONCLUSION: We conclude that an optimized high-resolution CRT system is quite promising for primary interpretation of digital portable chest radiographs, but further investigation and greater statistical power are necessary to confirm our results.

Chest imaging within the radiology department by means of photostimulable phosphor computed radiography: a review.

Photostimulable phosphor computed radiography has been clinically used outside of Japan for more than 8 years. Results of at least 35 quantitative or semiquantitative studies have been published so far in which the clinical utility of computed radiography (CR) is compared with that of conventional screen/film radiography (FR) for the study of the adult chest within the radiology department. The results can be summarized as follows: CR is superior to FR in the mediastinum, retrocardiac region, and subdiaphragmatic recesses, as well as in the evaluation of coronary artery calcifications. CR is reported to be generally superior or equivalent in the detection and evaluation of pulmonary nodules and larger pulmonary opacities. Equivocal results have been reported for pathologies requiring the inspection of fine details, such as interstitial infiltrates or pneumothorax. The studies indicate that image processing algorithms dedicated to the delineation of specific anatomies or pathologies improve clinical performance.

A distributed approach to integrated inquiry and display for radiology.

Picture archive and communications (PACS) systems should be flexible and modular in design so that new advances in storage, computation, and display technology can be introduced into the system without a significant redesign of existing software. The acquisition, storage, and management of radiologic images must be carefully integrated with a radiology information system. Our architecture is based on a four-level data model: (1) patient information, (2) examination information and reports, (3) image information, and (4) instances of images. The PACS being developed at the Mallinckrodt Institute of Radiology within the Electronic Radiology Laboratory consists of three primary components: application clients, database servers and image servers. One type of application client is an image-capable workstation that supports a radiology image viewing application. The application client queries the database server for information regarding patient and examination data in response to user-level requests. The database server responds to the request by retrieving the appropriate patient demographics and examination information, along with a pointer to the image/instance data from a central database. The client then uses the image data pointer to query the image server for the actual pixel data. The image server responds by transmitting the pixel data to the requesting application client or a designated auxiliary display device. Other clients act as image data acquisition nodes. Queries to the database servers are made via a library of callable subroutines. Software integrity is maintained throughout the system by dynamically loading software from a code-control database. Inquiry and display transactions, supported on a local-area network (Ethernet), have been measured and analyzed. Results and observations are presented.

Artifacts in computed radiography.

Storage-phosphor digital radiographic systems are becoming widely used in a variety of diagnostic procedures. The equipment is reliable and produces images of consistently high quality. However, the images may contain artifacts directly related to the digital techniques used, to the phosphor imaging plate, or to radiography in general. This article illustrates many of the artifacts encountered that are specific to computed radiography, some of which can simulate pathologic lesions. Their causes and remedies are discussed briefly.

MR examination of the knee: interpretation with multiscreen digital workstation vs hardcopy format.

A multiscreen imaging workstation was compared with conventional hardcopy format for diagnostic interpretation of MR images of the knee. MR examinations from 30 patients were interpreted by two observers using film displayed both on a standard film panel alternator and an eight-screen digital workstation. Arthroscopic examination of these patients disclosed 30 meniscal tears and five anterior cruciate ligament tears in 28 patients. Two patients had normal arthroscopic examinations. The MR examinations were evaluated with a five-point confidence rating scale. Results were correlated with arthroscopic findings, and receiver-operating-characteristic curves were generated from these data. No significant difference was found between the areas under the receiver-operating-characteristic curves for film and digital display. The time required for image interpretation was greater when using the digital workstation than when using the film by a factor of approximately 2.7. Our data indicate that a multiscreen digital workstation can be used for interpreting MR examinations of the knee without impairment of diagnostic performance, but with increased time required for image interpretation when compared with radiographic film and a film panel alternator.

A prototype of a high-resolution computerized radiology teaching file.

Computers provide an excellent tool for handling the task of organizing a radiology teaching file. Currently available computerized teaching files are either film-based, slide-based, or use laser-disc video technology for image display. There are obvious advantages to having the management of radiologic images under the control of a computer, and the need for a higher resolution alternative to video laser-disc technology becomes apparent when one tries to computerize a chest radiology teaching file. We describe the prototype of such a system, named MIRTLE, (the Mallinckrodt Institute of Radiology Teaching and Learning Environment) which was designed to integrate text under the control of a custom data base with high-resolution digital images from a Picture Archiving and Communications System. This system with its easy-to-use windows environment should allow a significant increase in the use of the radiology teaching file.

Hospital-wide distribution of nuclear medicine studies through a broadband digital network.

Nuclear medicine provides a good environment for the evaluation of picture archiving and communication systems (PACS) because of the relatively small quantity of digital data that are generated, leading to reduced requirements for storage, display, and transmission compared with those found in radiology. The PACS in nuclear medicine is characterized by use of a single computer as a central storage, display, and analysis node. Images are acquired with use of small, low-cost computers attached to each camera. This network configuration offers advantages of convenience, but with great reliance on a single computer. A campus-wide picture network is under development at Washington University employing broadband cable television technology supplemented by baseband Ethernet (Digital Equipment Corp, Maynard, MA) components. All areas of diagnostic radiology and nuclear medicine are connected via a PACS testbed project. A radiology information system, supporting over 250 terminals, provides digital tracking of patients and report generation and retrieval. A new image workstation is under development in conjunction with Digital Equipment Corp. This system will permit display in multiple windows of report information and images from various modalities. A lung scan demonstration project is now beginning that is designed to test the value of a PACS in nuclear medicine. Digitally acquired chest radiographs will be displayed on an image workstation in nuclear medicine along with digital ventilation and perfusion lung scans. It is hoped that time-consuming logistic bottlenecks now encountered in lung scan interpretation will be reduced.

Digital mobile radiography.

A storage phosphor digital imaging system has been used to perform virtually all of an increasing number of mobile (portable) projectional roentgenographic examinations in a busy hospital. Approximately 130 such studies are done per day, of which about 110 are chest examinations. The processing unit suffices to keep pace with peak activity in the radiology department. This technique has decreased the repeat rate for portable anteroposterior chest radiographic examinations from 4.5% to less than 1% and has resulted in an even more dramatic reduction in the rate for lateral or decubitus chest examinations as well as for studies of the abdomen and those done in the operating room. The diagnostic accuracy and confidence level achieved in interpreting the complementary pair of digital images has been equivalent to or has exceeded that obtained with conventional mobile analog film-screen radiographs.

Student analysis of imaging studies. A radiology clerkship exercise.

Senior radiology clerkships often must cope with medical students whose overly optimistic course goals are quite different from the objectives of the radiology faculty. Conference formats that satisfy both the clerks and the teachers are therefore difficult to design. We use a conference based on student assessments of radiology examinations that attracts student interest while accomplishing staff objectives. This learning session relies on student-prepared analyses of radiologic examinations. The five-year experience with this teaching method has been quite positive from the perspectives of students and the staff.

The senior radiology clerkship. Disparate goals of students and faculty.

A survey of medical students taking our radiology elective over the past five years revealed that 51% were chiefly interested in learning "to read x-rays." Other motivations for taking the elective, such as learning "radiographic workups" were relatively low-priority goals. On the other hand, a survey of our staff revealed a low priority placed on teaching medical students to interpret radiographic images and a high value placed on imparting an understanding of the role of radiology in clinical diagnosis and management. This disparity between the goals of the students and teachers delineates one of the major challenges in designing a radiology curriculum for medical schools.

Radiology reporting.

Several different computer methods have been developed to assist in the production of radiology reports. Some systems require the radiologist to interact directly with the computer; in other departments, it is the transcriptionist who types the report into a computer terminal. Automated reporting systems, if they are well designed, offer a significant benefit to most departments, providing an efficient method to produce, store, and distribute radiology reports.