Chest teleradiology in a teaching hospital emergency practice.

OBJECTIVE: New standards for hospital accreditation and health care reimbursement may require that faculty subspecialists be more available after regular working hours to supervise residents in academic radiology departments. We designed a receiver operating characteristic study to determine whether a thoracic radiologist who evaluated computed radiography (CR) images of the chest at a home-based teleradiology workstation could add significant value to a junior resident's interpretations of films within the hospital for acutely ill patients. SUBJECTS AND METHODS: Using a hybrid cassette, we obtained analog chest films and CR images simultaneously for each of 252 acutely ill patients in the emergency department and in an intensive care unit. Interpretations of the analog films by three first-year residents were analyzed for 11 parameters deemed critical for patient management. Likewise, CR images of the same chest studies were viewed on a home teleradiology workstation by a faculty thoracic radiologist who analyzed the images for these 11 interpretive parameters. All interpretations by radiology residents and by the home-based thoracic radiologist were then compared with the interpretations of a consensus panel consisting of another thoracic radiologist and a full-time emergency department radiologist. RESULTS: Analysis of the pooled results from the three junior residents as a group failed to show significant differences between their interpretations of chest films and the interpretations of CR images by a thoracic radiologist at a home workstation. However, we observed significant differences for several image interpretation parameters between individual residents and the home-based radiology subspecialist. CONCLUSION: The data confirm that significant value can be added to the interpretations of chest films by individual junior residents when a home-based thoracic radiologist uses teleradiology to provide expert interpretations. Accordingly, it is reasonable to infer that on-line supervision by faculty subspecialists via teleradiology could be used to complement the scheduled visits that are being made now by individual faculty members of our institution to interpret films periodically with a radiology resident during overnight and weekend periods.

Effect of conversion from a fee-for-service plan to a capitation reimbursement system on a circumscribed outpatient radiology practice of 20,000 persons.

PURPOSE: To assess the effect of a capitation reimbursement plan with attendant changes in service arrangements on the utilization of radiologic services, financially on the payer, and on the satisfaction of patients and referring physicians. MATERIALS AND METHODS: Outpatient radiologic services for a defined population of 20,000 company employees and their dependents were converted from a point-of-service managed care plan to a capitation payment plan. Under the capitation plan, nonemergent outpatient diagnostic imaging was performed at a newly constructed imaging center staffed by general radiologists. All cross-sectional images and certain projectional studies were also over-read (read again after the initial reading by local radiologists) by subspecialists. Utilization data obtained before and after the conversion were analyzed. The financial effect on the employer and the satisfaction of patients and physicians were also assessed. RESULTS: Quality imaging services were provided under the capitation plan with financial savings by the employer. Use was higher for cross-sectional imaging, especially magnetic resonance imaging studies, and was lower for nonmammographic plain radiography. Consumer satisfaction was high. CONCLUSION: Under certain conditions, conversion to a capitation system for imaging can lead to improved quality of care and decreased overall health-care costs.

Comparison of hard- and soft-copy digital chest images with different matrix sizes for managing coronary care unit patients.

OBJECTIVE: This study was to determine whether different digital display formats for portable chest radiographs of coronary care unit patients would provide comparable information for clinical care. In particular, we tried to ascertain whether 1024 x 1024 pixel (1K) images on a picture archiving and communication system (PACS) workstation would be comparable to 1760 x 2140 pixel (2K) images on workstations or to digital films. If comparability could be proved, we hypothesized that 1K workstations could considerably lower equipment and film costs and facilitate image transmission from point to point. MATERIALS AND METHODS: Four chest radiologists read a panel of chest studies assembled from 98 coronary care unit patients, comparing 1K and 2K soft-copy images with digital hard copies. For all three image types for the 98 patients, the readers evaluated nine image parameters that the cardiologists deemed essential for clinical decision making. Two other chest radiologists reviewed each patient's three image types, historical chest images, current and prior radiologic reports, and medical record to determine the consensus, or "truth findings." RESULTS: With one exception (small pleural effusions), the receiver operating characteristic analysis showed no significant differences in the clinical information derived from the three image types. CONCLUSION: For clinical management in a coronary care unit, comparable information can be obtained from digital radiologic chest studies using a 1K x 1K soft-copy format, a 2K x 2K soft-copy format, or a hard copy (film). Substantial savings in cost and time are therefore possible by using soft-copy images and lower resolution (1K x 1K) workstations and, when necessary, by transmitting images on regular telephone lines.

Technical considerations in planning a distributed teleradiology system.

A large-scale teleradiology project is under way to link a Florida imaging center to the UCLA Department of Radiology. The initial goal is to provide Florida patients in a routine clinical practice environment with subspecialty consultation by academic radiologists. The plan then calls for the addition of other domestic and international sites. Technical issues in planning to establish the necessary teleradiology infrastructure include wide area network design, image compression, distributed archiving, and special viewing station features. Special emphasis is placed on archive design that makes intelligent use of information, such as triggering events from the radiological information system (RIS) for image prefetching and visual cues from photo-icons for full-size image retrieval. Concepts such as teleconsultation and remote procedure monitoring are aimed at providing the same level of services at distant sites that would be available in-house. This article highlights the system design parameters that must be considered to engineer a scalable distributed teleradiology system.

Surveillance of patients with prostate cancer after treatment: the roles of serologic and imaging studies.

The asymptomatic patient who has been treated with a curative intent by surgery or irradiation for cancer of the prostate needs only a PSA and a baseline bone scan for his initial (post-treatment) follow-up. Rising serum PSA levels which still remain in the moderate range may signal a local recurrence, but this must be documented histologically. The therapeutic options to consider for a documented local recurrence include pelvic irradiation for the previously operated patient, or surgery for a post-irradiation recurrence. A serum PSA which rises to high levels following treatment will often be associated with distant metastases, and this is more certain if the original tumor was locally advanced and/or the histology was poorly differentiated or aneuploid. A newly elevated serum acid phosphatase in a treated patient with prostate cancer will usually signify disseminated disease also. Whether to wait until a patient becomes symptomatic from a recurrence or to initiate endocrine treatment solely on the basis of a rising serum marker still remains a point of controversy. The overall survival of Stage D2 patients has not been prolonged by endocrine manipulations which were instituted before symptoms of widespread dissemination appeared. The routine use of periodic imaging studies to follow asymptomatic patients with prostate cancer after they have received treatment cannot be justified for clinical decision-making purposes. On the other hand, in treated patients who develop new symptoms suggesting bone metastases, radionuclide scans which are correlated carefully with the patient's symptoms and with radiographs of "hot" areas on the scans are indicated. When a suspected diagnosis of metastatic disease still remains in doubt, elevated serum tumor markers may provide additional evidence. Imaging studies can also be used to guide percutaneous biopsies of suspected metastases in bones (radionuclide scans and radiographs), or of persistent tumor in an irradiated prostate gland or at the urethro-vesical junction after surgery (TRUS). Since cancer of the prostate often progresses slowly and disseminated disease remains incurable at this time, some degree of uncertainty about the presence of metastases or of recurrent local disease might be safer and less costly than the use of multiple diagnostic studies and aggressive treatment (including endocrine manipulations) in nonsymptomatic patients.

The pediatric patient with suspected adrenal neoplasm: which radiological test to use?

To establish which radiological test to use in a pediatric patient with suspected neoplasm, we retrospectively studied 19 children with proven adrenal neoplasm who had a combination of ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI). The results show that US should remain the initial imaging modality for evaluating abdominal masses in children but that MRI is more accurate than CT and US in detecting the organ of origin and the extent of an adrenal lesion and should, therefore, be the modality of choice for the definitive evaluation of adrenal neoplasm in children.

Mediastinal masses: magnetic resonance imaging in comparison with computed tomography.

Seventy-eight patients with mediastinal abnormalities were imaged with magnetic resonance imaging (MRI) to evaluate mediastinal masses and associated lung, pleural, or chest wall disease. Magnetic resonance images were compared with computed tomography (CT) scans, which were available in 45 patients. While MRI and CT were equally effective in demonstrating mediastinal lesions, CT was superior for displaying calcification within a mass in eight patients and for demonstrating associated lung abnormality in four patients. Computed tomography should remain the imaging procedure of choice after chest radiography to evaluate mediastinal masses, although MRI may be indicated in selected patients.

Routine imaging studies for the posttreatment surveillance of breast and colorectal carcinoma.

Current recommendations on follow-up procedures for patients who have been treated for cancer include imaging studies and other laboratory tests at relatively frequent intervals. At least two questions should be asked to evaluate the benefits of this practice for patients: Do frequent routine surveillance tests detect recurrences "earlier" in asymptomatic patients? and Does earlier treatment of these recurrences reduce morbidity or prolong survival? The practical import of surveillance with imaging and laboratory tests for recurrence in patients with cancer of the breast and colon is discussed. Reported autopsy data, findings at elective reoperation, and clinical data have been examined to ascertain the justification for routine periodic tests in the treated but asymptomatic patient. It is concluded that earlier detection of a local recurrence or of metastatic disease through periodic tests in the asymptomatic patient with breast or colon cancer rarely alters the treatment or the outcome. A notable exception is regular screening mammography following treatment for adenocarcinoma of the breast.

Metastatic tumors of unknown origin.

The clinical appearance of metastatic lesions without an obvious primary source for the tumor is a common event. Tumor Registry figures and epidemiologic data grossly understate the actual frequency of unknown primaries, because primary sites are often "assigned" to patients on a best-guess basis without positive proof of a tumor's origin. In the majority of patients whose primary tumors have continued to elude detection, the extensive use of diagnostic imaging studies fails to produce information that alters the patients' clinical course. Rare exceptions will be cited, but these exceptions prove the general rule. Imaging studies should therefore be targeted for selected patients with disseminated malignancies in whom identification of their primary tumors could benefit quality of life or length of survival.