Current opinion in radiology最新文献

Picture archiving and communication systems (PACS) are among the most promising information technologies in health care. They are, however, still in the development phase, and their implementation is taking longer than was predicted in the 1980s. Evaluation of these PACS implementations is also much more difficult than was expected. Local, very specific settings and lack of standard methodology make a comparison of tangible and intangible factors very cumbersome. This difficulty has resulted in very divergent opinions in the literature regarding the objectives, realizations, and achievements of PACS. Different approaches for image acquisition, processing, communication, and display have been supported in a wide variety of conferences and in a few key publications. Different approaches are particularly noticeable in Europe and are exemplified by a spectrum of single and multivendor PACS realizations. Some of the most significant of these developments are reviewed.

Compliance with screening mammography guidelines is affected by complex factors, including cost, accessibility, education, and attitudes of referring physicians. High-volume mammography facilities have lower fees and higher quality. Quality assurance is the focus of the voluntary American College of Radiology Mammography Accreditation Program, and over half of all mammography units are accredited. Nonetheless, pressure for mandatory quality standards is increasing. Mobile mammography reduces costs and increases access, but it presents challenges in financing and quality assurance. These screening issues, especially quality assurance, are not taught adequately in radiology residency training programs. Yet public awareness of the benefits of early detection has resulted in more lawsuits for failure to diagnose and delay in diagnosis. Preventive measures reduce medicolegal risks. On a personal level, the psychologic trauma of screening mammography is greater than was previously suspected. However, associated anxiety and stress do not seem to affect compliance with screening guidelines adversely.

Magnetic resonance imaging has played a role in the diagnosis of thoracic disease; however, the role has been limited compared with that of CT. In the past year, there were a few additional reports of MR imaging in the diagnosis of thoracic disease, which include a multi-institutional study comparing MR imaging with CT and histopathologic correlative studies evaluating gadopentetate dimeglumine-enhanced MR imaging. Furthermore, several excellent reviews of MR imaging of thoracic disease were published. In general, the recent literature supports information previously reported. In the future, developments in lung parenchymal imaging and pulmonary vascular imaging are anticipated.

The contribution of isotope imaging to the investigation of respiratory disease has been primarily limited to the detection of ventilation and perfusion abnormalities and the investigation of inflammation or cancer. In recent years, there has been a growing interest in the metabolic function of the lung and in measurements of alveolar capillary permeability in a variety of conditions. This review will deal with these newer applications of isotope techniques in the lung in addition to developments in ventilation-perfusion imaging.

Over the past year, concerns regarding breast cancer screening guidelines and the benefits of mammography have been raised. These concerns were fueled by a leak of information from the Canadian National Breast Screening study that suggested first an increase in mortality in women aged 40 to 49 years and then, after further investigation, no change in mortality for women screened with mammography as compared with those who relied on physical examination. No benefit from the addition of mammography to physical examination was reported for women aged 50 to 59 years. Published data demonstrate poor mammographic images in the first 3 years of the study. Direct evidence of benefit in women aged 40 to 49 years is available only in the Health Insurance Plan trial in which two-view mammography plus physical examination resulted in a delayed reduction in mortality equal to that in older women. The other trials, except for the Canadian trial, used less sensitive protocols and frequently used single-view mammography at 2- or 3-year intervals. Evidence from the Breast Cancer Detection Demonstration Project suggested benefit in screening women aged 40 years or older with annual mammography and physical examination. This paper reviews 11-year results from the Swedish two-county study and the results of other studies and discusses factors related to frequency, sensitivity, and lead-time.

Radiologic imaging plays a critical role in the management of congenital abnormalities affecting the tracheobronchial tree, lung parenchyma, pulmonary vessels, and the mediastinum. Although procedures such as bronchoscopy, bronchography, and angiography may at times still be required, diagnosis is now usually established noninvasively using ultrasound, CT, MR imaging, or radionuclide imaging techniques. Earlier diagnosis, even in the antenatal period, is possible, thus allowing more prompt and effective treatment. Patients with congenital abnormalities that were previously fatal in infancy and childhood are surviving into adulthood. Clinicians and radiologists alike must now be able to recognize congenital disorders in patients who may have minimal or absent symptoms.

The highlight of recent articles published on pediatric chest imaging is the potential advantage of digital imaging of the infant's chest. Digital chest imaging allows accurate determination of functional residual capacity as well as manipulation of the image to highlight specific anatomic features. Reusable photostimulable phosphor imaging systems provide wide imaging latitude and lower patient dose. In addition, digital radiology permits multiple remote-site viewing on monitor displays. Several excellent reviews of the imaging features of various thoracic abnormalities and the application of newer imaging modalities, such as ultrafast CT and MR imaging to the pediatric chest, are additional highlights.

Magnetic resonance spectroscopy provides information about metabolic processes in living tissues. The resulting information may be more sensitive and specific than that obtained using techniques that rely on functional or structural measurements. Although the preponderance of applications to date have been in physiologic investigations in animals, clinical applications are emerging. Reports in the past two years have appeared evaluating the clinical use of phosphorus spectroscopy to detect ischemic heart disease, cardiomyopathy, and cardiac transplant rejection. Active research using nuclei other than phosphorus for spectroscopy will expand the potential clinical applications. Technical developments, including improved surface coil design, wider use of high-field magnets and new pulse sequences, will allow improved sensitivity and spatial localization in the future.

Significant progress is being made in the field of pediatric cardiovascular imaging. The application of color Doppler transesophageal echocardiography has proven to be extremely useful in both intra- and perioperative examinations. The introduction of the long-axis pediatric probe has expanded the abilities of transesophageal imaging in clinical pediatric practice. MR imaging is continuing to evolve as a noninvasive imaging technique. The development of cine-MR imaging now permits simultaneous evaluation of cardiac anatomy and function and is forecasting a larger role for this technology. In the field of interventional cardiovascular radiology, there have been further reports describing percutaneous balloon valvoplasty both at valve and vascular levels, as well as the application of balloon expandable intravascular stents for a variety of obstructive lesions.

The past ten years have seen the introduction of a number of new techniques for the treatment of biliary diseases. In this report, we discuss the roles of both extracorporeal shock-wave lithotripsy and percutaneous treatment of gallstones, and we emphasize the changing role of these techniques since the advent of laparoscopic cholecystectomy. The literature on chemical cholecystectomy is reviewed with particular reference to experience in humans. Biliary endoprosthesis using expandable metallic stents is discussed in patients with benign and malignant biliary obstruction. Finally, we review the role of interventional radiologic procedures on liver transplant patients.