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S L Primack

Publications and source records attributed to S L Primack.

At least 19 recordsLinked to original sources
PubMed2001

High-resolution CT: normal anatomy, techniques, and pitfalls.

High-resolution CT (HRCT) as a technique has shown an increasing role in the evaluation of known or suspected lung disease. To accurately interpret HRCT, an awareness of normal lung and pleural anatomy is essential. Knowledge of optimal HRCT technique is necessary to avoid misinterpretation and increase diagnostic accuracy. In addition, the potential technical and patient-related pitfalls are many. This article discusses normal lung and pleural anatomy, the technique of HRCT, and potential technical and patient-related pitfalls of HRCT.

Algorithms↗
PubMed2000

Radiographic and CT findings in blunt chest trauma.

Injuries of the thorax are a major cause of morbidity and mortality in blunt trauma patients. Radiologic imaging plays an important role in the workup of the patient with thoracic trauma. The chest radiograph is the initial imaging study obtained, but computed tomography (CT) is now used frequently in the evaluation of chest trauma. The primary role of chest CT has been to assess for aortic injuries, but CT has been shown to be useful for the evaluation of pulmonary, airway, skeletal, and diaphragmatic injuries as well. Magnetic resonance imaging (MRI) has a limited role in the initial evaluation of the trauma patient, but may be of use for the evaluation of the spine and diaphragm in patients who are hemodynamically stable.

Aorta, Thoracic↗
PubMed1999

Chest radiology case exchange program: a paradigm for resident teaching and independent resident learning.

RATIONALE AND OBJECTIVES: The purpose of this study was to test the effectiveness of resident-prepared, independent learning cases in teaching residents chest radiology. MATERIALS AND METHODS: Three 2nd-year residents (one each from the University of Wisconsin, the Oregon Health Sciences University, and the University of Michigan) prepared four chest radiology teaching cases each (total, 12 cases). Radiology residents from each institution were randomly divided into control (n = 30) and experimental (n = 35) groups. Residents from both groups took a pretest of 36 multiple-choice questions covering the material from the 12 teaching cases. Residents in the experimental group reviewed these cases independently, and both groups took the same test (posttest) immediately after the teaching cases had been reviewed and again 3 months later (final test). RESULTS: Test scores were similar across institutions (P > .05) but differed across time and treatment groups (experimental vs control) (P < .0001). Mean differences in test scores between the experimental and control groups at pretest, posttest, and final test were -0.4, +9.0, +4.0, respectively, demonstrating increased performance at posttesting that was still present (though somewhat attenuated) 3 months later at final testing. CONCLUSION: Independent study of resident-prepared chest radiology teaching cases increases the resident's knowledge for as long as 3 months after instruction.

Analysis of Variance↗
PubMed1999

Medical students and radiology residents: can they learn as effectively with the same educational materials?

RATIONALE AND OBJECTIVES: The purpose of this study was to evaluate the effectiveness of resident-prepared, independent-learning materials for teaching chest radiology to medical students. MATERIALS AND METHODS: Students from three U.S. medical schools enrolled in radiology clerkships between March 1998 and June 1998 were randomly divided into control (n = 27) and experimental (n = 31) groups. The experimental group studied 12 chest radiology independent-learning cases (intervention) used to teach radiology residents in a previous study. Both groups took a 36-item, multiple-choice test (previously used to test radiology residents) on three occasions (before intervention [pretest], 1 day after intervention [posttest], and 2-4 weeks after intervention [final examination]). Student scores were then compared with resident scores. RESULTS: Mean scores were similar across institutions at pretest, but increases at posttest and final examination scores differed across time, school, and group (P < .005). Mean differences in scores between experimental and control groups at pretest, posttest, and 2-4-week final examination were -0.22, 9.79, and 9.14, respectively, demonstrating increased performance at posttesting that remained present (though slightly attenuated) 2-4 weeks later. Comparing performance, residents had mean pretest scores of 19.2 and students of 14.1, a five-point difference attributable to the residents' greater experience. Both residents and students gained approximately nine points at posttest. At final examination, the difference between residents and students was only 1.4 points, suggesting the experimental program (teaching materials) brought students close to the long-term retention shown by residents. CONCLUSION: Independent study of resident-prepared chest radiology teaching cases increased medical student knowledge for at least 2 or 4 weeks after instruction. Although starting at lower knowledge levels, students experienced gains in knowledge comparable to those of residents, suggesting the same materials can be used to teach both students and residents.

Education, Medical, Undergraduate↗
PubMed1999

Effectiveness of resident-prepared conferences in teaching imaging utilization guidelines to radiology residents.

RATIONALE AND OBJECTIVES: The authors evaluated the effectiveness of a resident-prepared conference series for teaching imaging utilization guidelines to radiology residents. MATERIALS AND METHODS: Brown University radiology residents (n = 17) gave 61 presentations on imaging utilization to their colleagues during 16 1-hour conferences. The residents were later examined on the topics presented and surveyed about their familiarity with the American College of Radiology appropriateness criteria, their exposure to issues of cost-effectiveness, and their degree of confidence in providing imaging consultation. The same examination and survey were administered to control residents from the University of Wisconsin (n = 14) and the Oregon Health Sciences University (n = 14). Scores were compared by using linear regression and Wilcoxon rank sum tests. RESULTS: Controlling for years in radiology residency, residents at Brown scored on average 16.0% (standard error = 2.2%) higher than residents at the other universities (P < .001). Controlling for institution, 3rd- and 4th-year residents scored on average 7.4% (standard error = 2.1%) higher than 1st- and 2nd-year residents (P = .001). Brown residents expressed more familiarity with American College of Radiology appropriateness criteria and appeared to have more exposure to cost-effectiveness issues in conferences than residents at Wisconsin or Oregon Health Sciences University (P < .005). Residents from the three universities did not differ in their level of confidence in providing imaging consultation. CONCLUSION: Resident-prepared conferences are an effective means of teaching imaging utilization guidelines to residents, but they do not affect the residents' perception of their ability to provide imaging consultation.

Diagnostic Imaging↗
PubMed1998

Radiologic manifestations of the systemic autoimmune diseases.

Advances in thoracic imaging during the past two decades, such as CT scans and MR imaging, have enhanced our understanding of the pleuropulmonary abnormalities that develop in the systemic autoimmune diseases. In this article, the thoracic radiologic manifestations of several connective tissue diseases (systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, polymyositis/dermatomyositis, progressive systemic sclerosis, and anklyosing spondylitis), two granulomatous vasculitides, (Wegener's Granulomatosis and Churg-Strauss syndrome), and antiglomerular basement membrane disease are reviewed.

Autoimmune Diseases↗
PubMed1997

Simulated dose reduction in conventional chest CT: validation study.

PURPOSE: To validate a technique of computer-simulated dose reduction for conventional chest computed tomography (CT). MATERIALS AND METHODS: In 27 patients, CT scans were obtained at 200, 100, and 40 mAs at two levels. The raw data from the 200-mAs scan were modified on a computer workstation to simulate the increased noise present on 100- and 40-mAs scans. Real and simulated 100- and 40-mAs images were independently assessed in random order for overall image quality and radiologic findings by four subspecialty-trained chest radiologists who were blinded to the technique. The four observers were given paired real and simulated images. They were asked to identify the real image and note any difference in diagnostic quality. RESULTS: No difference was seen in overall image quality or radiologic findings between real and simulated images (P > .05). In the paired comparison, 433 of 864 (50.1%) real images were correctly identified. CONCLUSION: Computer modification of 200-mAs raw scan data to simulate 100- and 40-mAs noise levels produces reconstructed images indistinguishable from real 100- and 40-mAs scans. This technique provides realistic reduced-dose images without patient radiation exposure and with identical image registration and motion artifact.

Adult↗
PubMed1996

Neofissure after lobectomy of the right lung: radiographic and CT findings.

PURPOSE: To document the postlobectomy radiographic and computed tomographic (CT) appearance of neofissures of the right lung. MATERIALS AND METHODS: Chest radiographs and CT scans from 25 patients who had undergone right lobectomy were assessed by two chest radiologists, and decisions on the findings were reached by consensus. Analyses included orientation of the neofissure and lobar reorientation of the remaining lobes. RESULTS: Neofissure location after right upper lobectomy (n = 13) was superior and anterior compared with the location of the left major fissure on both lateral radiographs and CT scans. After right middle lobectomy (n = 4), the neofissure had less vertical orientation than the left major fissure (the highest posterior portion was lower and the lowest anterior portion was higher than the left major fissure) on both lateral radiographs and CT scans. After right lower lobectomy (n = 8), two types of lobar reorientation and, accordingly, two types of neofissure were observed in the right lower lung zone (posteriorly and anteriorly high, respectively, on lateral radiographs). CONCLUSION: Analyses of neofissures on lateral radiographs and CT scans enable differentiation among various kinds of lobectomy.

Adult↗
PubMed1996

Disease progression in usual interstitial pneumonia compared with desquamative interstitial pneumonia. Assessment with serial CT.

OBJECTIVE: To determine the outcome of areas of ground-glass attenuation and assess disease progression on serial high-resolution CT (HRCT) scans of patients with biopsy specimen-proved usual interstitial pneumonia (UIP) and desquamative interstitial pneumonia (DIP). MATERIALS AND METHODS: Twelve patients with biopsy specimen-proved UIP and 11 patients with biopsy specimen-proved DIP who had initial and follow-up HRCT scans (median interval, 10 months) were reviewed. Eleven patients with UIP and 11 with DIP received treatment between the initial and follow-up CT scans. The scans were evaluated for the presence and extent of ground-glass attenuation, irregular linear opacities and honeycombing, and overall extent of parenchymal involvement. RESULTS: On initial CT scans, all 12 patients with UIP had areas of ground-glass attenuation (mean +/- SD extent, 30 +/- 16%) and irregular lines (mean +/- SD extent, 17 +/- 7%) and 10 patients had honeycombing (mean +/- SD extent, 10 +/- 6%). All 11 patients with DIP had areas of ground-glass attenuation on initial HRCT scans (mean +/- SD extent, 51 +/- 26%), 5 patients had irregular linear opacities (mean +/- SD extent, 5 +/- 5%), and 1 patient had honeycombing. Nine of the 12 patients with UIP showed increase in the extent of ground-glass attenuation (n = 6) or progression to irregular lines (n = 2) or honeycombing (n = 4) on follow-up as compared with only 2 patients with DIP who showed progression to irregular lines (n = 1) or honeycombing (n = 1) (p < 0.01 chi 2 test). CONCLUSION: In patients with UIP, areas of ground-glass attenuation usually increase in extent or progress to fibrosis despite treatment. Areas of ground-glass attenuation in most patients with DIP remain stable or improve with treatment.

Adult↗
PubMed1996

Detection and differential diagnosis of pulmonary infections and tumors in patients with AIDS: value of chest radiography versus CT.

OBJECTIVE: The purpose of this study was to compare the sensitivity and specificity of chest radiography with those of CT in the detection of pulmonary infections and tumors in patients with AIDS. MATERIALS AND METHODS: The study was retrospective and included the radiographs and CT scans of 139 patients. Eighty-nine had one proven thoracic complication, 17 had two proven thoracic complications, and 33 had no active intrathoracic disease at the time of the examinations. The radiographs and CT scans were interpreted blindly by two independent observers from different institutions. The observers assessed for the presence or absence of intrathoracic disease and recorded the most likely diagnosis and the degree of confidence in that diagnosis. RESULTS: The patients were more commonly correctly identified as having or not having intrathoracic disease on the basis of CT findings than on the basis of radiographic findings ( p < .01, chi-square test). Of the 106 patients with intrathoracic complications, 90% (191 of 212 interpretations) were correctly identified by the two observers on the radiograph and 96% (204 of 212 interpretations) at CT. Of 33 patients without intrathoracic disease, 73% (48 of 66 interpretations) were correctly identified at radiography and 86% (57 of 66 interpretations) at CT. Of 89 patients with one proved thoracic complication, the observers confident in their first-choice diagnosis in 34% of the cases (61 of 178 interpretations) at chest radiography and in 47% (83 of 178 interpretations) at CT. This diagnosis was correct in 67% (41 of 61) of confident radiographic interpretations as compared with 87% (72 of 83) of interpretations at CT (p < .01, chi-square test). CONCLUSION: CT is superior to chest radiography in allowing identification of patients with and without thoracic disease and in the differential diagnosis of pulmonary complications of patients with AIDS. However, the improvement in differential diagnosis is modest. Because in most cases the radiographs and CT scans were obtained as part of the clinical evaluation, the study is probably biased toward problematic clinical cases. In the majority of patients, the chest radiograph provides adequate information and CT is not warranted.

AIDS-Related Opportunistic Infections↗
PubMed1996

Diagnosis of diaphragmatic trauma with helical CT in a swine model.

OBJECTIVE: The purpose of this study was to determine whether diaphragmatic injury can be accurately diagnosed with helical CT in a swine model. The hypothesis of our study was that thin-section helical CT with sagittal and coronal reformations can reliably detect injury of the diaphragm. MATERIALS AND METHODS: The study was performed in a swine model because of the similarity of the swine thorax to the human thorax. Ten swine had a limited abdominal helical CT (enteral contrast; 3-mm collimation; pitch, 1) before and after surgical creation of a 6-cm posterolateral laceration in the left hemidiaphragm. A repeat scan was obtained after 5 cm of gastric fundus was sutured through the laceration. The gastric fundus was used because it is the most commonly herniated viscus in human diaphragmatic injury. No IV contrast was used. Control, laceration, and herniation scans were reconstructed with 1.0-mm overlap and reformated in axial, sagittal, and coronal planes. Three observers scored each reformation as control or injury (defined as laceration or herniation) in a blinded and randomized fashion. RESULTS: Using helical CT, the observers were able to distinguish diaphragmatic injury from controls (p < .0001). The sensitivity and specificity were 92% and 87%, respectively, for sagittal reformations; 85% and 87%, respectively, for coronal reformations; and 73% and 80%, respectively, for axial reformations. Sagittal reformations proved superior to coronal or axial reformations (p = .01). The results were independent of individual observers: We found no significant difference in accuracy among the three observers. CONCLUSION: Helical CT can accurately detect diaphragmatic injury in a swine model.

Animals↗
PubMed1995

Pulmonary tuberculosis and Mycobacterium avium-intracellulare: a comparison of CT findings.

PURPOSE: To compare the computed tomographic (CT) findings of tuberculosis and Mycobacterium avium-intracellulare (MAI) infection in immunocompetent patients. MATERIALS AND METHODS: Seventy-seven consecutive immunocompetent patients with culture-proved pulmonary mycobacterial infection (45 with pulmonary tuberculosis, 32 with MAI) underwent thin-section CT. CT scans were randomized and reviewed by two observers; decisions were reached by consensus. RESULTS: Micronodules, consolidation, and cavity formation in the lung were seen with similar frequency in pulmonary tuberculosis and MAI cases. Twenty-three patients (51%) with tuberculosis and four patients (12%) with MAI had interlobular septal thickening (P < .001). Twelve patients (27%) with tuberculosis and 30 patients (94%) with MAI had bronchiectasis (P < .001). Bronchiectasis was seen in a mean of 4.6 +/- 1.8 and 1.8 +/- 1.6 lobes (+/- standard deviation) in each patient with MAI and with tuberculosis, respectively (P < .01). CONCLUSION: Although CT findings of pulmonary tuberculosis and MAI are similar, interlobular septal thickening is more common in patients with tuberculosis and bronchiectasis is more common and more extensive in patients with MAI.

Adolescent↗
PubMed1995

Acute lung disease in the immunocompromised host. Diagnostic accuracy of the chest radiograph.

PURPOSE: To assess the diagnostic accuracy of the chest radiograph in the evaluation of acute pulmonary complications in immunocompromised patients. METHODS: The study included the chest radiographs in 149 consecutive acute pulmonary complications seen in immunocompromised patients in whom a definitive diagnosis was made. Twenty-four complications were in patients with AIDS and 125 were in non-AIDS patients. The radiographs were separately reviewed in random order by two independent observers. The observers assessed pattern and distribution of radiographic findings and recorded their first-choice diagnosis. RESULTS: The most common complication in patients with AIDS was Pneumocystis carinii pneumonia (n = 21). In the non-AIDS patients, the most common complications included invasive aspergillosis (n = 25), drug reaction (n = 21), and Pneumocystis pneumonia (n = 20). A correct first-choice diagnosis was made in 90% of patients with AIDS and 34% of non-AIDS patients. IN AIDS patients with Pneumocystis pneumonia, the correct first-choice diagnosis was made in 41 of 42 (98%) readings by the two observers. In non-AIDS patients with invasive pulmonary aspergillosis, drug reaction, and Pneumocystis pneumonia, the correct first-choice diagnosis was made in 38%, 26%, and 43% of readings, respectively. CONCLUSION: The chest radiograph is helpful in the differential diagnosis of acute lung disease in the immunocompromised host, particularly in patients with AIDS.

Acquired Immunodeficiency Syndrome↗