摘要:

The development of effective methods for producing digital chest radiographs is essential if the totally digital radiology department of the future is to evolve. Digital radiography of the chest is now possible with a variety of techniques. The most promising approach currently in clinical use involves the use of large-area detectors composed of photostimulable phosphors read with a laser to produce high-quality digital chest images. Image processing to modify contrast and latitude of the image display as well as enhancement of selected spatial frequencies and energy subtraction is possible with digital chest radiography. The wide exposure latitude of digital image receptors may allow useful images to be obtained with significantly smaller exposure doses than those required in conventional techniques and may also be used to compensate for inadvertent overexposure, eliminating the need for repeat examinations because of errors in exposure technique. Limitations of many current systems result from inadequate resolution provided by CRT display monitors. The production of hard copy images by laser printer on small format film overcomes this problem, allowing application of digital techniques for chest radiology to be incorporated into clinical practice with images comparable in spatial resolution to those of film-screen systems.

ISSN:0883-5993    

出版商:OVID    

年代:1985

数据来源: OVID

摘要:

The conventional chest radiograph has a number of limitations as a diagnostic method of evaluating chest disease. The wide variation in attenuation between the lung and mediastinum frequently results in images with low contrast over the thicker portions. This, coupled with the presence of intense body-scattered radiation that must be adequately removed, makes chest radiography one of the most challenging diagnostic procedures in conventional radiography. Scanning equalization radiography (SER) is an alternative method of chest imaging that overcomes these limitations without employing other highly complex or expensive solutions such as digital imaging. Recent clinical studies have shown that diagnostic efficacy is improved with SER, and that SER offers the potential of significantly reducing the frequency of diagnostic errors and repeated examinations while producing cost savings.

ISSN:0883-5993    

出版商:OVID    

年代:1985

数据来源: OVID

摘要:

With current high-resolution equipment and proper case selection, intravenous digital subtraction angiography (IVDSA) can consistently demonstrate pulmonary emboli greater than 2.0 mm in size. IVDSA is less traumatic than conventional pulmonary angiography and is preferable for high-risk cases such as patients with pulmonary arterial hypertension. For successful IVDSA studies patients should be able to hold their breath for 10 to 20 seconds. IVDSA should not be used in patients who are extremely dyspneic, who cannot suppress a cough, or who have a low cardiac output. In these instances selective intraarterial DSA is preferable.

ISSN:0883-5993    

出版商:OVID    

年代:1985

数据来源: OVID

摘要:

Plain-film tomography is a quick, accurate, and inexpensive procedure that is valuable for the evaluation of two common problems in chest radiology—the solitary pulmonary nodule and the hilus that is questionably abnormal. An accurate diagnosis can be made in most patients with a solitary pulmonary nodule so that appropriate management can be undertaken. If the diagnosis of an indeterminate nodule is made, further evaluation with computed tomography, transthoracic needle aspiration biopsy, surgery, or careful radiographic follow-up can be suggested. Hilar tomography can determine whether the appearance of the hilus on the chest radiograph is due to prominent but normal vessels, an enlarged pulmonary artery, enlarged hilar lymph nodes, or a pulmonary mass.

ISSN:0883-5993    

出版商:OVID    

年代:1985

数据来源: OVID

摘要:

Because of greatly enhanced contrast resolution and the advantages of cross-sectional visualization of lung anatomy, computed tomography (CT) has the potential to add significantly to the conceptualization of parenchymal lung disease. Although the value of CT has been well documented in the detection and characterization of lung nodules, the role of CT has been less clearly defined for other types of lung disease. This report describes the CT appearance of distal air-space disease. As demonstrated by the use of inflated and contrast-injected lungs obtained at autopsy, air-space disease is definable by the following: poorly marginated nodules ranging up to 1 cm in size; coalescence of nodules; air-bronchograms and air-alveolograms; ground-glass opacification; and distinct zonal patterns of distribution, including central and peripheral configurations. These patterns of air-space abnormalities are further refined by review of case material, including examples of air-space disease secondary to aspiration and primary intraalveolar disease, evaluated by the authors over a five-year period.

ISSN:0883-5993    

出版商:OVID    

年代:1985

数据来源: OVID

摘要:

A series of patients with documented predominantly interstitial pulmonary disease was examined by routine and high-resolution computed tomography (CT) and compared to a series of twenty-one normals. Inspiratory-expiratory lung density measurements were also obtained at predetermined levels. Several basic CT signs of interstitial disease were identified: (1) finely irregular and thickened pleural surfaces; (2) irregular vascular shadows; (3) thickened and irregular bronchial walls making bronchi visible over a longer portion of their course in the lungs; (4) reticular network of lines with three patterns easily distinguishable by the size of their reticular element; (5) hazy patches of increased density of various sizes distinguishable from alveolar filling processes by the fact that vessels can still be visualized through them; and (6) nodules of various sizes. Micronodules are often associated with a small or medium-size reticular network and in most cases seem to represent points of confluence rather than isolated nodules. The hematogenous origin of some nodules can be specifically suggested when feeding vessels arc demonstrated on thin-section scans. Nodules associated with a large network of thickened septa are suggestive of lymphangitic carcinomatosis. Inspiratory-expiratory density gradients can be more useful in confirming the diagnosis of interstitial disease than absolute measurements.

ISSN:0883-5993    

出版商:OVID    

年代:1985

数据来源: OVID

摘要:

Magnetic resonance imaging (MRI) takes advantage of physical properties of matter that are radically different from those that result in radiographic contrast, and therefore, has the potential to provide unique diagnostic information. During the last three years, the author's experience with MRI has suggested that this technique can be advantageous in evaluating some patients with chest disease. Although results to date remain somewhat preliminary, they serve to illustrate some of the strengths as well as weaknesses of this technique.

ISSN:0883-5993    

出版商:OVID    

年代:1985

数据来源: OVID

摘要:

The use of paramagnetic contrast agents in magnetic resonance imaging (MRI) of the lungs and mediastinum has been the subject of preliminary investigation. Gadolinium-DTPA (Gd3+-DTPA) is a suitable intravenous paramagnetic contrast agent for imaging cerebral tumors and liver tumors. Its use in the thorax is more speculative, but early animal experimental data suggest that contrast-enhanced MRI may have a place in the assessment of pulmonary edema and lung parenchymal damage.

ISSN:0883-5993    

出版商:OVID    

年代:1985

数据来源: OVID

摘要:

Positron emission tomography using the ECAT II scanner to image and measure regional lung function is outlined. The combined use of transmission and emission imaging provides quantitative information about regional lung structure (density, extravascular density, and vascular volume) and function (ventilation, perfusion, ventilation-perfusion ratios, glucose metabolic rate). Clinical applications in asthma, chronic obstructive lung disease, pulmonary vascular disease, interstitial lung disease, and squamous cell carcinoma are presented. Future prospects for PET are discussed.

ISSN:0883-5993    

出版商:OVID    

年代:1985

数据来源: OVID

摘要:

Although ultrasound of the thorax has been used mainly for studying the heart, it is also of value for the examination of pathologic conditions in the chest other than cardiac disease and can be used to complement the diagnostic information obtained by other imaging techniques. In addition, ultrasound of the lower thorax is frequently performed “inadvertently” when the upper abdomen, the liver, and the heart are being examined sonographically. Pathologic lesions in the chest may be seen during such examinations and it is therefore important to be familiar with their appearances.

ISSN:0883-5993    

出版商:OVID    

年代:1985

数据来源: OVID