PubMed Health⌕ Search

Biomedical subjects

S L Primack

Publications and source records attributed to S L Primack.

At least 19 recordsLinked to original sources
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↗
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↗
PubMed1995

Diffuse pulmonary hemorrhage: clinical, pathologic, and imaging features.

Diffuse pulmonary hemorrhage (DPH) is a syndrome characterized by the presence of widespread hemorrhage from the pulmonary microvasculature leading to hemoptysis, iron deficiency anemia, and a chest radiography showing bilateral airspace consolidation. Diagnostic imaging consists primarily of chest radiography, but CT and MR imaging may be helpful in selected cases. There are many causes of DPH, and the differential diagnosis and diagnostic approach depend on whether the patient is immunocompetent or immunocompromised. This review summarizes the clinical, pathologic, and imaging features of DPH and the treatment of its more common causes.

Anemia, Iron-Deficiency↗
PubMed1995

CT of the chest: minimal tube current required for good image quality with the least radiation dose.

OBJECTIVE: We wanted to determine minimal tube current (mAs) required for consistently good image quality on conventional 10-mm collimation chest CT and effect of tube current reduction on detection of mediastinal and lung abnormalities. Tube current reduction is desirable to reduce patient radiation dose. SUBJECTS AND METHODS: Prospectively, 30 consecutive patients (mean weight, 68 kg; range, 34-93 kg) older than 45 undergoing conventional chest CT with standard technique (120 kVp, 400 mAs) had four additional sections imaged at reduced tube current (200, 140, 80, 20 mAs) at two levels (tracheal carina and left atrium). CT scans were evaluated in random order by two independent observers who were blinded to technical factors used. Subjective image quality was graded on a five-point scale from non-diagnostic to excellent. Visualization of mediastinal adenopathy (n = 18), pleural plaques (n = 17), effusions (n = 28), lung parenchymal nodules (n = 37), and emphysema (n = 15) were assessed. The 400 mAs scan was considered the reference standard. RESULTS: When compared with the reference technique (400 mAs), the first and second (200 mAs and 140 mAs) reduction levels showed no significant difference (p > .05) in subjective image quality. A significant difference (p < .001) was seen at the third and fourth (80 mAs and 20 mAs) reduction levels. However, no significant difference (p > .05) was seen in detection of mediastinal or lung parenchymal abnormalities with different tube currents. CONCLUSION: A twofold reduction in tube current (400-140 mAs) and resultant radiation dose did not cause a significant change in subjective image quality or in detection of mediastinal or lung abnormalities with conventional chest CT. One hundred forty milliampere-seconds is the minimal tube current required to provide good image quality in patients of average weight.

Aged↗
PubMed1995

Perforated atherosclerotic ulcer of the aorta presenting with upper airway obstruction.

The authors describe an unusual presentation of penetrating atherosclerotic ulcer of the aorta in an 84-year-old man. The ulcer perforated the aorta, and hematoma extended into the soft tissues of the neck, causing upper airway and esophageal obstruction. The results of autopsy proved the findings of prior chest radiography and computed tomography.

Aged↗
PubMed1994

Pulmonary parenchymal abnormalities of vascular origin: high-resolution CT findings.

High-resolution computed tomography (HRCT) is a proved imaging modality for use in assessment of infiltrative lung disease. Findings suggestive of infiltrative lung disease on HRCT scans include ground-glass attenuation, consolidation, nodules, and interlobular septal thickening. Similar patterns, however, may be caused by various vascular abnormalities including regional or diffuse increase in blood flow, pulmonary edema, pulmonary hypertension, and thromboembolism. A correct diagnosis can usually be made by careful analysis of the pulmonary vasculature. Parenchymal abnormalities of vascular origin are associated with increased or decreased vessel diameter, vascular compression, or intraluminal filling defect.

Humans↗
PubMed1994

CT of bronchial and bronchiolar diseases.

Computed tomography (CT) is useful in evaluating bronchial and bronchiolar abnormalities. Common bronchial and bronchiolar abnormalities include bronchiectasis, asthma, bronchial obstruction, and various forms of bronchiolitis. Causes of bronchiectasis include cystic fibrosis, childhood viral infection, allergic bronchopulmonary aspergillosis, and pulmonary fibrosis. On CT scans, cystic fibrosis may manifest with bronchial wall thickening, bronchiectasis (usually cylindrical, with varicose and cystic forms seen in advanced cases), and mucus plugs in the bronchi. Allergic bronchopulmonary aspergillosis is characterized by central, varicose or cystic bronchiectasis, predominantly in the upper lobes, with mucoid impaction in the bronchi. Traction bronchiectasis may be seen on CT scans of pulmonary fibrosis. Asthma is characterized by bronchial wall thickening due to inflammation. Bronchial dilatation and air trapping may also be seen. Bronchiolitis obliterans is manifested by direct and indirect signs on CT scans; the former consist of centrilobular branching structures and nodules, and the latter consist of bronchiectasis and bronchiolectasis, mosaic perfusion, and air trapping. CT findings of bronchiolitis obliterans organizing pneumonia (also known as cryptogenic organizing pneumonia) include air-space consolidation and nodules, with occasional bronchial dilatation and pleural effusions.

Adult↗
PubMed1994

Pulmonary nodules and the CT halo sign.

PURPOSE: To determine whether the "halo sign" at computed tomography (CT) could be used to differentiate hemorrhagic from nonhemorrhagic pulmonary nodules. MATERIALS AND METHODS: CT scans of 12 patients with hemorrhagic pulmonary nodules and of a control group of 10 patients with nonhemorrhagic pulmonary nodules were randomized and reviewed by two chest radiologists. Nodules were considered hemorrhagic if a surrounding halo of ground-glass attenuation was present. RESULTS: Nodules were correctly identified as either hemorrhagic or nonhemorrhagic by both observers in 19 of the 22 cases (86%). Eight of the 12 patients with hemorrhagic nodules had an infectious process including invasive aspergillosis, candidiasis, cytomegalovirus, herpes simplex virus, or coccidioidomycosis. Four of 12 patients with hemorrhagic nodules had a noninfectious cause including Wegener granulomatosis, metastatic angiosarcoma, and Kaposi sarcoma. CONCLUSION: Most hemorrhagic pulmonary nodules have a characteristic CT appearance consisting of a central area of soft-tissue attenuation with a surrounding halo of ground-glass attenuation that allows distinction from nonhemorrhagic nodules.

Adult↗