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R M Steiner

Publications and source records attributed to R M Steiner.

At least 19 recordsLinked to original sources

Viral burden and disease progression in HIV-1-infected patients with sickle cell anemia.

The spleen and lymph nodes are major sites of human immunodeficiency virus type 1 (HIV-1) replication, mutation, and genetic variation in vivo. If a major portion of the lymphatic tissue, such as the spleen, is removed or otherwise is unavailable for invasion by the HIV-1 virus, will the course of the infection be altered, resulting in a prolonged symptom-free interval or even increased survival? The spleen of most adults with sickle cell anemia (SS) is nonfunctional due to recurrent episodes of microinfarction. If autosplenectomized SS patients are exposed to HIV-1, they may be ideal candidates to examine the question of whether absence of splenic function at the time of infection will positively alter the course of HIV-1-related disease. All SS patients with a diagnosis of HIV-1 infection at five university sickle cell centers were included in the patient cohort. Patients in active treatment or in follow-up (group A, n = 11) underwent a series of quantitative viral studies to determine their HIV-1 viral burden. The studies included the branched-DNA signal amplification assay, quantitative DNA-polymerase chain reaction (PCR), quantitative reverse transcription (RT)-initiated-PCR, and in situ PCR. All patients who died of the complications of the acquired immunodeficiency syndrome (AIDS) or of SS, lost to follow-up, or were otherwise unavailable for study (Group B: n = 7) were included in the total patient group. None of the patients in group B underwent quantitative viral studies. In addition, a control population (group C, n = 36) of HIV-1-infected African Americans without SS, of similar age and gender to the SS patients, were compared with the study population for outcomes. In eight of 11 active patients (group A), the CD4+ T-lymphocyte counts were normal and viral burdens were low for an average of 10.25 years following diagnosis. These eight patients all from group A were the only long-term nonprogressors (44%) among a total of 18 SS patients (groups A and B). In group C (control), only five patients of 36 were long-term nonprogressors (13.9%). Five patients (28%) of the total SS group (groups A and B) succumbed to AIDS. One of the five was from Group A. The evaluation of a limited number of adult individuals suggests that a significant proportion of HIV-1-seropositive SS patients (44%) may be asymptomatic long-term nonprogressors. In these patients, the CD4+ T-lymphocyte counts remained high and their viral burdens were remarkably lower than in non-SS HIV-1-seropositive individuals. Whereas this study does not prove an "autosplenectomy" hypothesis, it suggests that in patients with both SS and HIV-1 infection, the retroviral disease may be ameliorated by host factors of which absence of splenic function prior to HIV-1 infection may be one.

Adolescent↗

Ventilator-associated pneumonia in patients with adult respiratory distress syndrome: CT evaluation.

PURPOSE: To determine the diagnostic accuracy of computed tomography (CT) for pneumonia in patients with adult respiratory distress syndrome (ARDS). MATERIALS AND METHODS: CT scans were obtained within 1 week of bronchoscopic sampling in 31 patients receiving mechanical ventilation for ARDS for more than 48 hours. Of 11 patients with pneumonia, five developed symptoms less than 11 days after the onset of ARDS (early ARDS). CT scans were rated for pneumonia independently by four radiologists who were unaware of the clinical diagnosis. Diagnostic accuracy was defined by means of the area under the receiver operating characteristic curve, or A2. RESULTS: Diagnostic accuracy for pneumonia was fair (A2 = 0.69 +/- 0.04 [standard error]) owing to 70% true-negative ratings (vs 59% true-positive ratings). The generalizability coefficient was good (0.79). No single CT finding was significantly different for the presence of pneumonia. Nondependent opacities predominated in 10 (91%) of 11 patients with pneumonia and 12 (60%) of 20 without pneumonia. Nondependent opacities predominated in nine (56%) of 16 patients with early ARDS and 13 (87%) of 15 with late ARDS. CONCLUSION: CT has fair diagnostic accuracy for ventilator-associated pneumonia in patients with ARDS owing primarily to identification of patients without pneumonia. No single CT sign was significantly different for pneumonia, but dependent atelectasis was more common in patients with early ARDS without pneumonia.

Adolescent↗

Analysis of cell type and radiographic presentation as predictors of the clinical course of patients with bronchioalveolar cell carcinoma.

STUDY OBJECTIVES: Bronchioloalveolar carcinoma is a primary lung neoplasm of variable histopathologic, radiologic, and clinical expression. There are three cell types described in bronchioloalveolar carcinoma: Clara cells, mucin-producing cells, and alveolar type II epithelial cells. It is unclear whether these three tumor cell types are associated with a specific radiologic presentation and clinical course. In this study, we investigated whether tumor cell type, identified by transmission electron microscopy, correlated with a specific radiologic pattern, and whether tumor cell type or radiologic presentation correlated with the patient's clinical course and outcome. DESIGN: Transmission electron microscopy was used to restudy tissue blocks from the original surgical histopathologic specimens in 54 patients with primary bronchioloalveolar carcinoma diagnosed over a 10-year period (1980 to 1990). The pretreatment radiographs were reviewed in each case, and the first chest radiograph obtained at the time of the discovery of the tumor in each patient was compared with the results of the ultrastructural study. The medical records of each patient were examined to obtain pertinent radiologic, clinical, and patient outcome information. MEASUREMENT AND RESULTS: There were 32 Clara cell tumors, 10 mucin-producing cell tumors, and 1 alveolar type II epithelial cell tumor in this series. Eleven additional tumors had mixtures of two or more cell types. No statistically significant relationship was detected between tumor cell type and radiologic presentation or patient mortality pattern. There was increased mortality among patients who presented radiologically with segmental, lobar, multifocal, or diffuse disease compared with those patients exhibiting a solitary pulmonary nodule at presentation. CONCLUSION: Radiologic presentation, rather than tumor cell type, provides prognostic information that aids in predicting patient outcome.

Adenocarcinoma, Bronchiolo-Alveolar↗

A pilot study of intermittent intravenous cyclophosphamide for the treatment of systemic sclerosis associated lung disease.

OBJECTIVE: Pulmonary fibrosis, a frequent manifestation of systemic sclerosis (SSc), is considered incurable. Our aim was to assess the effect of therapy with intravenous (i.v.) cyclophosphamide on the course of pulmonary fibrosis in patients with SSc. METHODS: Five patients with SSc and clinical, laboratory, or radiographic findings of interstitial lung disease were treated with cyclophosphamide (1 g) administered i.v. monthly for 48 weeks. The dyspnea score, pulmonary function tests, arterial blood oxygen content, radiologic abnormalities, and bronchoalveolar lavage (BAL) fluid cellularity were determined before and after therapy. RESULTS: The dyspnea score decreased by 42% after 48 weeks of therapy. Forced vital capacity (FVC, percentage of predicted) increased by 7%, and carbon monoxide diffusing capacity (DLCO) decreased by 12%, but these changes were not statistically significant. Arterial blood oxygenation remained unchanged. At baseline, high resolution computed tomography of the lungs showed honeycombing, reticulonodular, or ground glass patterns in each patient examined. These radiologic abnormalities did not improve during treatment. A marked decrease in BAL fluid cell number, but not in the percentage of neutrophils, was observed after therapy. Nausea and leukopenia were frequent but mild side effects. One patient developed hemorrhagic cystitis. CONCLUSION: The results suggest that intermittent treatment with i.v. cyclophosphamide reduces the severity of dyspnea, but fails to improve FVC or DLCO, or cause resolution of radiologic abnormalities, in patients with SSc.

Adult↗

Image-guided localization for video-assisted thoracic surgery.

Video-assisted thoracic surgery (VATS) has become a useful diagnostic and therapeutic tool in the management of lung, pleural, and mediatstinal disease. Preoperative image-guided localization is performed to aid the surgeon in the thoracoscopic resection of small lung lesions that would otherwise be difficult to resect. This article describes the techniques of localization and reviews our experience with this procedure. While the majority of localization procedures are performed during an immediately preoperative computed tomography (CT), the use of intraoperative lesion localization using an endosonographic probe has been reported. The need for localization before resection is dependent on the skill and experience of the thoracoscopist and the characteristics of the lung lesions.

Endoscopy↗

Outcome in sarcoidosis. The relationship of relapse to corticosteroid therapy.

STUDY OBJECTIVE: To determine the demographic, clinical, and radiographic characteristics of corticosteroid-treated patients with sarcoidosis who developed relapse following a period of clinical stability lasting longer than 1 month, and to compare these characteristics with those of a group of patients with sarcoidosis who were not treated. DESIGN: Historic, concurrent and prospective, nonrandomized, observational study. SETTING: Ambulatory sarcoidosis clinic in a university city hospital. PATIENTS: Over a 4-year calendar period, 337 patients with sarcoidosis were prospectively enrolled in a registry. One hundred eighteen patients were assigned to a spontaneous remission group when symptoms resolved without treatment, and 103 were assigned to an induced remission group when symptoms resolved following corticosteroid therapy and successful discontinuation. In 116 patients assigned to a recalcitrant group, therapy could not be stopped for 1 month or more owing to severity of symptoms or lack of compliance. We defined relapse as a recurrence of symptoms of sufficient severity to warrant treatment with corticosteroids, following a remission without treatment lasting greater than 1 month. INTERVENTION: Patients who were judged to be sufficiently symptomatic to preclude observation without treatment or who failed to respond to conservative treatment with topical or inhaled corticosteroids or nonsteroidal anti-inflammatory agents were treated with systemic corticosteroids at a target dose of 20 mg prednisone per day for 1 year. MEASUREMENTS AND RESULTS: We observed a 74% relapse rate in the induced remission group, but only an 8% relapse rate in the spontaneous remission group (p < 0.01). Relapse occurred with similar frequency in whites and African-Americans (20% vs 28%), despite a lower treatment rate in white patients than in African-Americans (43% vs 76%; p < 0.01). White patients maintained a sustained remission with twice the frequency of African-Americans (58% vs 29%; p < 0.01). During relapse, 40% of chest radiographs showed no change in type, but there was a significant increase in interstitial profusion (p < 0.05). Initial presentation with asymptomatic chest radiographic abnormalities, erythema nodosum, or peripheral adenopathy portended a favorable prognosis, with sustained remission in 60% of such patients lasting 130 +/- 226 months from time of diagnosis. In contrast, patients who presented with musculoskeletal complaints were nine times, and those with symptoms from hepatic involvement were three times more likely to suffer relapse than to sustain remission without receiving corticosteroids. Most relapses (50%) occurred between 2 and 6 months after discontinuing steroid therapy, but late relapse was not unusual, occurring more than 12 months after discontinuing steroid therapy in 20% of patients with induced remission. CONCLUSIONS: Relapse occurred frequently in patients with sarcoidosis who had been treated with corticosteroids, and rarely occurred in patients who had not been treated with corticosteroids in the past. The striking difference in relapse rate between treated and untreated patients suggests that patients with disease that would later be severe and protracted were almost unerringly identified early in their course. One explanation is that severe presenting symptoms portend a protracted and recurrent course; an alternative explanation is that corticosteroids contributed to the prolongation of the disease by delaying resolution.

Adult↗

Sonographic guidance for the localization of peripheral pulmonary nodules during thoracoscopy.

OBJECTIVE: The value of sonographic guidance during video-assisted thoracoscopic surgery (VATS) was studied in 13 patients with one or more peripheral pulmonary nodules who later underwent wedge resection. SUBJECTS AND METHODS: After a review of the chest radiographs and CT scans of each patient, sonographic guidance for VATS was requested by the attending surgeon when the nodule or nodules in question were determined to be too small or too deep in the lung parenchyma from the pleural surface for location by VATS. A multifrequency (5.0-, 6.5-, or 7.5-MHz) sonographic probe was introduced through a thoracoscopic port during VATS. The nodule or nodules in question were located by intraoperative sonography or determined by inspection and confirmed by sonography before wedge resection. The size and location of each lesion and the time needed for sonographic guidance were recorded. RESULTS: Sonography revealed a peripheral pulmonary nodule in 12 of the 13 patients. Of these, it confirmed the suspected location of the pulmonary nodule in six. In the remaining six patients, the surgeon was unable to locate the nodule without the use of sonography. The additional operative time required for sonographic guidance during VATS averaged 7.5 min. However, the time commitment of radiology personnel during surgery varied and was sometimes lengthy (maximum, 150 min). CONCLUSION: Sonographic guidance during thoracoscopy helped to locate lesions and determine their size and proximity to pleural surfaces. Sonographic guidance can be done safely and can be completed expeditiously. Unlike percutaneous hookwire techniques, sonographic guidance does not require an additional invasive procedure to locate the peripheral pulmonary nodule.

Aged↗

The relationship of thoracic lymphadenopathy to pulmonary interstitial disease in diffuse and limited systemic sclerosis: CT findings.

OBJECTIVE: Mediastinal lymphadenopathy is frequently associated with interstitial lung disease (ILD) in patients with systemic sclerosis (SSc). This study compared the extent of lymphadenopathy in diffuse and limited SSc with the presence and type of ILD found on CT scans. SUBJECTS AND METHODS: Seventy-three patients with diffuse and limited SSc underwent thoracic CT. The presence of lymphadenopathy was correlated with the frequency and type of ILD. RESULTS: Fifty-eight percent (18/31) of patients with diffuse cutaneous SSc and 40% (17/42) of patients with limited cutaneous SSc had lymphadenopathy. A significant relationship was found between lymphadenopathy and the presence of interstitial disease (p = .0002). Seventy-two percent (18/25) of patients with a ground-glass parenchymal pattern of interstitial disease and 74% (14/19) of patients with a honeycomb pattern had lymphadenopathy. CONCLUSION: Lymphadenopathy is prevalent in patients with SSc and ILD regardless of clinical subtype or interstitial pattern. Lymphadenopathy appears to increase as a function of the profusion rather than the morphology of ILD.

Female↗

A history of radiology and radiation oncology at Thomas Jefferson University.

The Departments of Radiology and Radiation Oncology have evolved during the last 100 years from a small combined facility into two large comprehensive departments characterized by the highest quality of patient care. Both departments, now under the direction of David C. Levin and Walter J. Curran, Jr., are leaders in graduate education and research productivity. As a result, both departments clearly represent another golden age in the history of radiology at Thomas Jefferson University.

Administrative Personnel↗

Role of thoracoscopy and preoperative localization procedures in the diagnosis and management of pulmonary pathology.

Video-assisted thoracic surgery is an important component of modern thoracic surgery, providing a safe, less invasive alternative to open thoracotomy in the evaluation of pleural, mediastinal, and parenchymal pathology. Advancements in endoscopic techniques and video-optics have permitted greater visualization of the thoracic cavity and allowed limited pulmonary resections with significantly reduced postoperative morbidity. Thoracoscopy is indicated for diagnosis of intrathoracic pathology when usual methods of diagnosis, including fine-needle aspiration and transbronchial biopsy, are inconclusive. The diagnostic accuracy of video-assisted thoracic surgery approaches 100%. Increasingly, the indications for thoracoscopy include therapeutic resections of pulmonary nodules in cases of limited lung metastases and bronchogenic carcinoma when pulmonary function is poor. Successful diagnostic and therapeutic resection by thoracoscopy requires intraoperative localization of the lesion within the collapsed lung. The indications and methods of thoracoscopic surgery and preoperative localization are discussed.

Biopsy, Needle↗

Congenital heart disease in the adult patient: the value of plain film chest radiology.

Congenital heart disease (CHD) is a major clinical problem in children, occurring in 0.8% of newborns (1). In the past, most patients with CHD died in infancy. With improved surgical and postoperative care, as well as more accurate preoperative evaluation, the overall 10-year survival rate is > 90%. As a result, > 500,000 adults in the United States have surgically treated CHD (2). In addition, at least 150,000 adults are thought to have unrecognized, misdiagnosed, or recognized but untreated CHD (3,4). Diagnostic imaging procedures for the evaluation of CHD include plain film radiology, fluoroscopy, angiocardiography, echocardiography, scintigraphy, computed tomography (CT), and magnetic resonance imaging (MRI). Each has unique as well as overlapping abilities to characterize precisely cardiovascular anatomy and pathophysiology. We emphasize those congenital cardiac disorders found predominantly in adults. In addition, conditions that are usually unrecognized in childhood, "slip through the system", and become clinically recognized in adults for the first time, often with an atypical clinical presentation, are discussed (5). The interpreter of the plain film radiograph has a unique opportunity to identify and often characterize the severity of a congenital cardiac disorder that may be unrecognized by the patient's physician. Important clues found on plain film radiographs will suggest either additional studies to pin-point the type of CHD more precisely or that no additional studies are needed because the recognized lesion is incidental and not of clinical significance.

Adult↗

Filter wheel equalization for chest radiography: a computer simulation.

A chest radiographic equalization system using lung-shaped templates mounted on filter wheels is under development. Using this technique, 25 lung templates for each lung are available on two computer controlled wheels which are located in close proximity to the x-ray tube. The large magnification factor (> 10X) of the templates assures low-frequency equalization due to the blurring of the focal spot. A low-dose image is acquired without templates using a (generic) digital receptor, the image is analyzed, and the left and right lung fields are automatically identified using software developed for this purpose. The most appropriate left and right lung templates are independently selected and are positioned into the field of view at the proper location under computer control. Once the templates are positioned, acquisition of the equalized radiographic image onto film commences at clinical exposure levels. The templates reduce the exposure to the lung fields by attenuating a fraction of the incident x-ray fluence so that the exposure to the mediastinum and diaphragm areas can be increased without overexposing the lungs. A data base of 824 digitized chest radiographs was used to determine the shape of the specific lung templates, for both left and right lung fields. A second independent data base of 208 images was used to test the performance of the templates using computer simulations. The template shape characteristics derived from the clinical image data base are demonstrated. The detected exposure in the lung fields on conventional chest radiographs was found to be, on average, three times the detected exposure behind the diaphragm and mediastinum.(ABSTRACT TRUNCATED AT 250 WORDS)

Biophysical Phenomena↗

Participation by radiologists and other specialists in percutaneous vascular and nonvascular interventions: findings from a seven-state database.

PURPOSE: To determine the relative degree of participation by radiologists and other specialists in percutaneous interventional procedures. MATERIALS AND METHODS: By using 1992 Medicare Part B claims data that covered seven states, the specialty of the physician provider was determined for all services performed within various percutaneous vascular and nonvascular interventional procedure codes. RESULTS: Radiologists' performance of interventional procedures in descending percentage of participation was as follows: renal cyst aspiration (92.7%), biliary decompression (90.5%), abdominal or retroperitoneal mass biopsy (87.7%), lung or mediastinal biopsy (84.2%), noncardiac angioplasty (76.8%), pancreatic biopsy (75.2%), upper urinary tract decompression (73.7%), liver biopsy (43.7%), renal biopsy (38.4%), certain types of abscess drainages (38.2%), and thoracentesis with tube insertion (29.4%). They had only small roles in thoracentesis for aspiration (4.7%) and tube thoracostomy (1.7%). CONCLUSION: Despite controversy between radiologists and other specialists over who should perform percutaneous interventions, radiologists have maintained strong predominance in many types of these procedures. In others, they have a shared, but still major, role.

Angioplasty, Balloon↗

The value of ultrasound-guided fiberoptic bronchoscopy.

Flexible fiberoptic bronchoscopy is the procedure of choice for the diagnosis of endobronchial neoplasm. Because of technical limitations of fiberoptic bronchoscopy, the use of ultrasound assistance was initiated and evaluated. This article reviews the technique, study design, and clinical results of ultrasound-assisted fiberoptic bronchoscopy.

Adult↗

The practice of chest radiology in departments with residency programs.

OBJECTIVES: The authors assessed to what extent radiology teaching programs employed dedicated chest radiologists and their functions. METHODS: Information regarding the clinical, teaching, and research role of the chest radiologist was available from responses to a survey of radiology departments with residency training programs in the United States and Canada. Emphasis was placed on the role of chest subspecialists, "dedicated chest radiologists" (DCRs), who spent at least two thirds of their clinical time interpreting and directing chest-related imaging studies and procedures. RESULTS: Among the 171 residency programs that responded, 118 had DCRs. There were 262 full-time and 233 part-time DCR positions, of which 43 were not filled. Among departments with DCRs, 66% were medical school programs while the remaining 34% were independent or medical-school-affiliated programs; 30% were organized by organ system, 5% by technology, and 65% had a combination of both; and 78% had more than 12 residents. DCRs interpreted routine chest radiographs in 96%, critical care radiographs in 94%, chest computed tomography (CT) studies in 72%, and chest magnetic resonance imaging (MRI) studies in 44% of their departments. Departments without DCRs were usually smaller, 70% having 12 or fewer residents. Their designated chest radiologists interpreted all chest radiographs in 21%, all critical care radiographs in 19%, all chest CT studies in 13% and all chest MRI studies in 8% of these departments. CONCLUSIONS: Dedicated chest radiologists were more involved than non-DCRs in all aspects of chest imaging, teaching, and research including analysis of image quality and acquisition of new technology. The highest quality of chest radiology training, defined as programs in which the chest fellowship positions were filled in 1991, was found in departments in which DCRs interpreted all chest radiographs, all chest CT studies, and most MRI studies.

Canada↗

Single breath-hold pulmonary magnetic resonance angiography. Optimization and comparison of three imaging strategies.

RATIONALE AND OBJECTIVES: Ultrafast gradient-recalled-echo techniques for obtaining high-quality pulmonary magnetic resonance angiograms within a single breath-hold were optimized. METHODS: Fourteen subjects were imaged with both the body coil and a phased-array surface coil, using three gradient-recalled-echo pulse sequences: 1) two-dimensional sequential; 2) two-dimensional interleaved; and 3) volumetric acquisitions. Image quality was assessed with varied flip angle, receiver bandwidth, slice thickness/number, and matrix size. Cardiac compensation diminished ghost artifacts in the interleaved sequence. Individual sagittal sections and maximum intensity projections were reviewed. RESULTS: Pulmonary magnetic resonance angiograms acquired with volumetric and two-dimensional interleaved gradient-recalled-echo pulse sequences benefit greatest from intravenous gadolinium and result in greater pulmonary arterial visualization than traditional time-of-flight techniques. Phased-array coils result in improved vessel detection. CONCLUSIONS: High-quality breath-held pulmonary magnetic resonance angiography can be obtained with an intravenous contrast-enhanced gradient-recalled-echo acquisition; however, image quality is dependent on the pulse sequence.

Adult↗

US-assisted bronchoscopy with use of miniature transducer-containing catheters.

PURPOSE: To demonstrate the value of ultrasound (US) guidance during flexible bronchoscopic procedures in a series of patients with known or suspected pulmonary neoplasms. MATERIALS AND METHODS: US-guided bronchoscopy was carried out as an adjunct to conventional bronchoscopy for the diagnosis of mediastinal, hilar, or parenchymal neoplasms in 25 patients with masses previously detected with chest radiography or computed tomography. Miniature transducer-containing catheters were inserted through the biopsy port of the flexible bronchoscope, and cross-sectional real-time US scans of tumors, lymph nodes, and blood vessels were obtained. RESULTS: Among six cases of peripheral masses and 19 cases of central masses, additional information was provided in 18 cases (72%). This information was used to choose the optimal site for transmural biopsy. CONCLUSION: These preliminary results suggest that this US procedure may become an important diagnostic tool during bronchoscopy, due to the ability to identify structures beyond the lumen of the tracheobronchial tree.

Adult↗