Teleradiology.

Teleradiology refers to the transmission of radiographic images from one location to another. Most of the work to date has involved scanning of conventional radiographs at clinics and other medical facilities with no full-time radiologist and transmitting the images to a medical center or hospital, where they are viewed on a television monitor and interpreted by a diagnostic radiologist. In this article, the author describes the 1982 and 1984 Teleradiology Field Trials, the objectives of which were (1) to compare the quality of film and video images in the field, which involved determination of sensitivity, specificity, and overall accuracy under both sets of viewing conditions; (2) to evaluate the reliability, maintenance, and communication functions of the teleradiology system; (3) to determine the costs involved in developing such a system and for day-to-day operation; and (4) to formulate recommendations for hardware, software, communication protocols, operating procedures, staff qualifications, and training requirements for future systems. Today, commercially available systems include high-speed digitization of radiographs, data compression, local storage, automatic transmission, selective retrieval, image enhancement, and interfacing with conventional computer systems.

The Johns Hopkins radiology reporting system.

Radiologists can comprehensively report diagnostic radiographs by computer with a speed approaching that of dictation. This is the main mode of radiographic reporting used at the Johns Hopkins Hospital. Support functions include information storage, retrieval, statistics, and billing. Costs are comparable to stenography. The system can be run from a large time-sharing computer or dedicated minicomputer. A commercial stand-alone version will soon be available.

ROC-study of a teleradiology workstation versus film readings.

PURPOSE: We have used receiver operating characteristic (ROC) analysis to compare screen assessment of digitized radiographic films transmitted by a teleradiology system, with evaluation of the original radiographs on film. MATERIAL AND METHODS: The material contained 120 cases (about 50% with selected pathology) that were difficult to diagnose. Four radiologists each evaluated half of the cases on film, and half on computer screen. The screen display was 1024 x 836 pixels with 8 bits/pixel. RESULTS: We found the accuracy and sensitivity of the teleradiology system to be clearly inferior to film evaluation. CONCLUSION: Improvement is needed both in the teleradiology system, and in the training of radiologists to work on the electronic workstation.

Teleradiology: results of a field trial.

A microcomputer-based teleradiology system was tested over a six-month period by linking a medical center with four distant clinics. Data from more than 4,000 diagnostic x-ray examinations were digitized and transmitted from the clinics to the center, where they were displayed on video terminals and interpreted by 30 military and civilian radiologists. The original radiographs were interpreted independently and the video and film reports compared to determine the feasibility of the teleradiology system. Evaluation of the clinical effectiveness of the system indicated that the quality of the video images resulted in diagnostic findings and impressions that were somewhat less accurate than those reported from comparable film images.

Teleradiology: an evaluation of a microcomputer-based system.

A laboratory evaluation of a microcomputer-based teleradiology system is described. The system used state-of-the-art hardware, and provided for contrast and brightness control by the consulting radiologists. The transmitted, digitized images were compared with conventional radiographs. The radiologists' scores for findings, impressions, and confidence levels were significantly lower for radiographic images viewed on the teleradiology system. However, the quality of the images provided by the teleradiology system was high enough to warrant further study, especially since microcomputer-based teleradiology offers the advantage of providing access to radiology services for rural areas and small hospitals.

Computer-assisted radiology reporting: quality of reports.

Automated medical communication systems for patient care usually enhance timeliness and retrievability. The effect of automated systems on communication quality has not been sufficiently measured. The radiology reports produced with the automated radiology reporting system at the Johns Hopkins Hospital were evalueate for quality and compared to reports produced by dictation. No differences in quality between computer-generated and dictated reports were detected by three consultant radiologists using a specially designed quality rating system.

Receiver operating characteristic analysis of fracture and pneumonia detection: comparison of laser-digitized workstation images and conventional analog radiographs.

Forty pneumonia and 40 fracture cases were matched by patient age and gender with normal cases. Pediatric cases constituted 25% of this sample. All 160 examinations were laser-digitized at a spot size of 210 microns, a contrast resolution of 12 bits, and a spatial resolution of 2.35 line pairs per millimeter. The digitized images were transmitted 5 miles over a dedicated telephone line at a T1 rate from Francis Scott Key Hospital to Johns Hopkins Hospital (both in Baltimore, Md). At Johns Hopkins Hospital, eight radiologists interpreted the original analog radiograph and corresponding soft-copy display (1,280 x 1,024 pixels). Findings, confidence ratings, and image quality were reported for each reading. A receiver operating characteristic (ROC) analysis was conducted to compare observer performance under the analog and digital reading conditions. The overall sensitivity of the analog method was 89% versus 78% for the digital method (P < .001), while the specificity values were 96% and 92%, respectively (P > .20). ROC analysis similarly indicated a statistically significant difference in favor of analog radiographs (P = .028).

Interpretation of Emergency Department radiographs: a comparison of emergency medicine physicians with radiologists, residents with faculty, and film with digital display.

OBJECTIVE: We determined the relative value of teleradiology and radiology resident coverage of the emergency department by measuring and comparing the effects of physician specialty, training level, and image display method on accuracy of radiograph interpretation. MATERIALS AND METHODS: A sample of four faculty emergency medicine physicians, four emergency medicine residents, four faculty radiologists, and four radiology residents participated in our study. Each physician interpreted 120 radiographs, approximately half containing a clinically important index finding. Radiographs were interpreted using the original films and high-resolution digital monitors. Accuracy of radiograph interpretation was measured as the area under the physicians' receiver operating characteristic (ROC) curves. RESULTS: The area under the ROC curve was 0.15 (95% confidence interval [CI], 0.10-0.20) greater for radiologists than for emergency medicine physicians, 0.07 (95% CI, 0.02-0.12) greater for faculty than for residents, and 0.07 (95% CI, 0.02-0.12) greater for films than for video monitors. Using these results, we estimated that teleradiology coverage by faculty radiologists would add 0.09 (95% CI, 0.03-0.15) to the area under the ROC curve for radiograph interpretation by emergency medicine faculty alone, and radiology resident coverage would add 0.08 (95% CI, 0.02-0.14) to this area. CONCLUSION: We observed significant differences between the interpretation of radiographs on film and on digital monitors. However, we observed differences of equal or greater magnitude associated with the training level and physician specialty of each observer. In evaluating teleradiology services, observer characteristics must be considered in addition to the quality of image display.

Subtle orthopedic fractures: teleradiology workstation versus film interpretation.

The purpose of this study was to evaluate whether radiologists perform equally well with plain radiographs or digitized images displayed on a video monitor in interpretation of difficult orthopedic trauma cases. Interpretations with film and those made from a teleradiology system with spatial resolution of 2.35 line pairs per millimeter were compared in 120 difficult cases, 60 with the selected abnormality (ie, fracture or dislocation) and 60 that were control cases. Seven senior radiology residents and one radiology fellow each interpreted 60 randomly ordered cases with the teleradiology system (1,280 x 1,024-pixel monitors) and 60 cases with the original radiographs. The overall accuracy of the readers was 80.6% for film interpretations and 59.6% for teleradiology screen readings (P < .001). Sensitivity was 78.5% for film and 48.8% for on-screen images (P < .001), and specificity was 83.2% for film and 72.3% for on-screen images (P < .025). Receiver operating characteristic analysis showed rejection of the null hypothesis in favor of film interpretation (P < .0049). It was concluded that the teleradiology system was not acceptable for primary diagnostic interpretation of difficult fracture cases.

Interpretation of emergency department radiographs by radiologists and emergency medicine physicians: teleradiology workstation versus radiograph readings.

PURPOSE: To compare accuracy of interpretation by radiologists and emergency medicine physicians of conventional radiographs and digitized images on a workstation. MATERIALS AND METHODS: One author selected 120 radiographs from the radiology department library, including 62 musculoskeletal, 20 abdominal, and 38 chest examinations. Analog radiographs were digitized. There were 60 positive and 60 control cases. Positive cases demonstrated clinically important disease and had a high degree of diagnostic difficulty. Thirty-one cases were judged to be critical to the patient's immediate care, requiring prompt accurate interpretation. Four groups of readers were used: staff radiologists and emergency medicine physicians and second-year radiology and emergency medicine residents. RESULTS: All reader groups performed better when interpreting conventional radiographs than digitized images. Differences in favor of radiograph reading were statistically significant for overall accuracy related to all cases and to critical cases (P < .05, one-tailed test). CONCLUSION: Results with the teleradiology system were found unacceptable for primary interpretation of the spectrum of radiographs seen in an emergency department.