Search PubMed⌕ Search

Biomedical subjects

R M Steiner

Publications and source records attributed to R M Steiner.

At least 55 records · Page 3Linked to original sources

Infection with Mycobacterium avium complex in patients without predisposing conditions.

Pulmonary disease caused by Mycobacterium avium complex usually occurs in patients with chronic lung disease or deficient cellular immunity, and its prevalence is increasing. We describe 21 patients (mean age, 66 years) with such infection without the usual predisposing factors, representing 18 percent of the 119 patients surveyed. Seventeen women and 4 men were given a diagnosis of M. avium complex from 1978 to 1987, with a stable incidence over the decade, on the basis of pulmonary symptoms, abnormalities on chest films, positive cultures, and in 14, biopsy evidence of invasive disease. Most of the patients (86 percent) presented with persistent cough and purulent sputum, usually without fever or weight loss. The cough was present for a mean of 25 weeks before the correct diagnosis was made. Radiographic patterns of slowly progressive nodular opacities predominated (71 percent); only five patients had cavitary disease at presentation. All patients responded initially to antimycobacterial therapy, but eight eventually relapsed when it was stopped. Four patients died of progressive pulmonary infection caused by M. avium complex. The extent of the initial pulmonary involvement was greater in patients with progressive disease than in those whose condition improved. We conclude that pulmonary disease caused by the M. avium complex can affect persons without predisposing conditions, particularly elderly women, and that recognition of this disease is often delayed because of its indolent nature.

Acquired Immunodeficiency Syndrome↗

Cross-sectional imaging of the chest wall.

Computed tomography and magnetic resonance imaging are now commonly performed for a variety of pulmonary and mediastinal lesions. However, some of the lesions that affect these areas also involve the chest wall. These include tumors, infections, trauma, and congenital processes. In such cases, a knowledge of chest wall anatomy combined with careful analysis of cross-sectional images is necessary to make the diagnosis. This article describes the basic cross-sectional anatomy of the chest wall and the principal pathologic chest wall lesions.

Humans↗

Clinical experience with rapid acquisition cardiovascular CT imaging (cine CT) in the adult patient.

In this overview of cine-CT technology and its clinical application, the authors discuss the unique features of the imaging unit and describe the scanning programs and projections available for cardiac studies. Application of the unit to physiologic studies (e.g., cardiac output and ejection fractions) are illustrated, and examples of the value of the unit for the diagnosis of septal defects, aortic dissection, valvular regurgitation, prosthetic value malfunction and coronary artery bypass graft occlusion are presented.

Cardiac Output↗

The prevalence of avascular necrosis in sickle cell anemia: correlation with alpha-thalassemia.

The purpose of the present study was to investigate the effect of alpha-thalassemia on the prevalence of avascular necrosis in 52 adult patients with sickle cell anemia. alpha-Globin genotypes were determined by restriction endonuclease mapping of genomic DNA extracted from peripheral blood leukocytes. Radiographs of humeral and femoral heads were interpreted by two radiologists who were not aware of the clinical picture and the genotype of the patients in the study. We present data showing that there is a significant positive correlation between alpha-gene deletion and the prevalence and extent of avascular necrosis in our patient population.

Adult↗

Assessment of lung water by magnetic resonance in three types of pulmonary edema.

Pulmonary edema was produced in nine mongrel dogs by: (a) saline lavage; (b) intravenous injection of oleic acid; and (c) intravenous injection of propranolol followed by ureteral ligation. The resulting effect could be characterized by varying the protein concentration in the pulmonary edema fluid. After induction, all dogs were killed and 20 samples from each passively deflated lung were obtained. Proton T1 and T2 values were measured on a Praxis II NMR spectrometer operated at 10.7 MHz and 37 degrees C. The water content of all samples was determined gravimetrically. Correlation between T1 or T2 measured in vitro and the ratio of wet to dry weight was highly significant (r greater than 0.95, P less than 0.001) in each pathological state. Regression curves indicate that although all three types of pulmonary edema can be characterized by slightly different slopes, the differences are statistically insignificant. Moreover, the slopes of previous studies, when recast in the same format, are very similar to our findings despite the use of different magnetic field strengths and different animal models. This study indicates that quantitation of pulmonary edema is possible, but in vitro measurements do not give useful information for characterizing the etiology of pulmonary edema.

Animals↗

The radiology of cardiac valve prostheses.

The radiographic findings associated with the complications of valve implantation are presented. Complementary roles of echocardiography and cine fluoroscopy in the recognition of complications associated with this procedure are emphasized. Identification of prosthetic valves and the knowledge of the modes of action of the various types of valves are stressed.

Bioprosthesis↗

Pseudoaneurysm of the ascending aorta following cardiac surgery.

Pseudoaneurysm of the ascending aorta is an unusual and potentially fatal complication of cardiovascular surgery. Most pseudoaneurysms are associated with aortic valve or coronary artery bypass graft surgery and are often mycotic in origin. Chest roentgenography and aortography have been the principle methods of diagnosis. Recently, contrast enhanced computed tomography (CT) has proven to be a useful means of diagnosis, providing a less invasive method of distinguishing pseudoaneurysm from other causes of fever and mediastinal widening in the postoperative cardiovascular patient. Thirty one cases of postoperative pseudoaneurysm of the ascending aorta occurring since 1963 are reviewed, including seven cases from our experience.

Adolescent↗

Obstructive emphysema due to mucus plugging in quadriplegia.

A quadriplegic patient with obstructive emphysema caused by mucus in the bronchi of the hyperinflated lung, demonstrated by chest radiograph and corrected by bronchoscopic aspiration of secretions from the hyperexpanded side, is reported. Subsequently, this phenomenon recurred in the opposite lung. This case is of particular interest, as it is the only documented report of obstructive emphysema due to mucus plugging in an adult with grossly normal airways. This case contrasts markedly with the usual picture of atelectasis and lobar or segmental collapse observed with large airway obstruction by mucus in this setting.

Adult↗

Bronchoalveolar cell carcinoma of the lung.

A multivariable analysis was performed of all patients registered and confirmed to have bronchoalveolar cell carcinoma of the lung in the Tumor Registry of Thomas Jefferson University Hospital between 1969 and 1983. These 122 patients were reviewed for age, sex, smoking history, occupational exposure, symptoms, radiographic findings, methods of diagnosis, clinical and pathologic staging, methods of treatment, survival, and complications of treatment. No correlation could be found in this series between a patient's age, sex, smoking history, or occupational exposure and the incidence or outcome of the disease. Seventy-one of the 122 patients in this series were asymptomatic, and the carcinoma was discovered in them by routine chest roentgenogram. Of these asymptomatic patients, 50 were seen with pathologic stage I disease. Of the 51 symptomatic patients, 32 (65%) were seen with stage IIIm0 or IIIm1 disease. Despite medical evaluations, 77% of the T1 and T2 lesions required thoracotomy for diagnosis. The overall five-year survival rate was 42.3%, ranging from 75% for those with stage I disease to 8.7% for those with stage IIIm1 disease.

Adenocarcinoma, Bronchiolo-Alveolar↗

Painful sickle cell crisis: bone marrow patterns observed with MR imaging.

Eleven patients with homozygous sickle cell anemia (SCA) undergoing painful crisis were studied with magnetic resonance (MR) imaging. The signal intensity of bone marrow was diffusely decreased in the axial and peripheral skeleton on short repetition time (TR)/echo time (TE) images and long TR/TE images, which suggested hematopoietic marrow hyperplasia and was confirmed by isotope marrow scans in five patients. Focal areas of further decrease in signal intensity were seen on short TR/TE images in 12 of the 14 (86%) painful joints and three of the five (60%) painless joints. In the painful joints, these focal areas converted to high signal intensity on long TR/TE images, presumably due to edema, which suggested acute marrow infarction. In the painless joints, these low-intensity focal areas remained as low signal on long TR/TE images, which suggested absence of edema and thus areas of old infarction or fibrosis. These results indicate that MR imaging may enable differentiation between acute and chronic marrow infarcts in patients with SCA and serve as a useful guide in monitoring and directing therapy.

Adult↗

Clinical applications of magnetic resonance imaging (MRI) of the heart.

The rapid progress of MRI has been remarkable, and it is clear that it will become an important method for cardiac imaging. Its major advantages are the lack of ionizing radiation and the ability to obtain excellent global images of the cardiac walls and chambers without the need for contrast injection or cardiac catheterization. High resolution surface coil imaging, tissue spectroscopy, and other improvements and applications should be rapidly forthcoming.

Coronary Disease↗

Multimodality approach to pericardial imaging.

In this chapter, three modalities--computed tomography, nuclear magnetic resonance imaging, and echocardiography--have been discussed. Each of these techniques offers unique advantages in the diagnosis of pericardial disease. Although echocardiography is the least expensive, most sensitive, and least invasive technique for the identification of pericardial effusion, false-positive and negative studies may be encountered. These are often resolved with the use of computed tomography and may be resolved with magnetic resonance imaging. Plain film radiography still has the advantage of identifying pericardial calcifications and will suggest the diagnosis of large pleural effusions at low cost and radiation dose. Exquisite portrayal of cross section anatomy using CT will aid in the diagnosis of multiple small tumor deposits and will clearly identify pericardial thickening. The value of magnetic resonance imaging awaits carefully controlled blinded studies, but its role in characterization of the content of pericardial effusions appears especially promising.

Cardiomyopathy, Restrictive↗