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B S Leitman

Publications and source records attributed to B S Leitman.

At least 19 recordsLinked to original sources
PubMed1998

Pulmonary nodule detection: low-dose versus conventional CT.

PURPOSE: To quantitate the effectiveness of low-dose computed tomography (CT) in the identification of pulmonary nodules while controlling for anatomic nodule characteristics and to establish what factors lead to reduced diagnostic sensitivity at low-dose CT. MATERIALS AND METHODS: Each of six participating radiologist independently rated 200 image panels by using a four-point confidence scale. Conventional images were obtained at 200 mAs; low-dose images were obtained at 20 mAs. To fully control their characteristics, nodules were simulated with a given diameter, shape, and section thickness while preserving the resolution, noise level, and reconstruction artifacts of the original images. Panels were matched so that nodules on low-dose and conventional images had equivalent sizes, locations, and relationships to blood vessels. RESULTS: Among 864 positive panels, 259 (60%) of 432 low-dose panels and 272 (63%) of 432 conventional panels were correctly interpreted (P = .259). Lowering the x-ray dose significantly reduced the detectability of peripheral nodules (P = .019) and nodules separated from blood vessels (P = .044). Surprisingly, 3-mm nodules were detected with approximately equal sensitivity (P = .181) at conventional and low-dose CT. The specificity of low-dose images was 88% (148 of 168 panels) versus 91% (153 of 168 panels) for conventional images (P = .372). CONCLUSION: Low-dose CT is acceptable for pulmonary nodule identification, making it suitable for primary screening. These results confirm the strong effect of size, location, and angiocentricity on the sensitivity of nodule detection with conventional CT.

Computer Simulation↗
PubMed1996

Diffuse lung disease: assessment with helical CT--preliminary observations of the role of maximum and minimum intensity projection images.

PURPOSE: To evaluate assessment of diffuse lung disease with helical computed tomography (CT) and maximum intensity projection (MIP) and minimum intensity projection images. MATERIALS AND METHODS: Six patients with suspected lung disease (the control group) and 20 patients with documented disease underwent axial helical CT through the upper and lower lung fields. Findings on the MIP and minimum intensity projection images of each helical data set were compared with findings on the thin-section scan obtained at the midplane of the series. RESULTS: Owing to markedly improved visualization of peripheral pulmonary vessels (n = 26) and improved spatial orientation, MIP images were superior to helical scans to help identify pulmonary nodules and characterize them as peribronchovascular (n = 2) or centrilobular (n = 7). Minimum intensity projection images were more accurate than thin-section scans to help identify lumina of central airways (n = 23) and define abnormal low (n = 15) and high (ground-glass) (n = 8) lung attenuation. Conventional thin-section scans depicted fine linear structures more clearly than either MIP or minimum intensity projection images, including the walls of peripheral, dilated airways (n = 3) and interlobular septa (n = 3). MIP and minimum intensity projection images added additional diagnostic findings to those on thin-section scans in 13 (65%) of 20 cases. CONCLUSION: MIP and minimum intensity projection images of helical data sets may help diagnosis of a wide spectrum of diffuse lung diseases.

Adult↗
PubMed1995

Unusual lymphoproliferative disorders in nine adults with HIV or AIDS: CT and pathologic findings.

PURPOSE: To identify characteristic computed tomographic (CT) findings in unusual pulmonary lymphoproliferative disorders seen in adults with the human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS). MATERIALS AND METHODS: The authors retrospectively reviewed the CT scans and pathologic specimens from nine patients with pulmonary lymphoproliferative disorders. CT scans were evaluated for nodules, reticulation, areas of ground-glass attenuation, consolidation, and bronchial disease. Changes seen in pathologic specimens were classified as consistent with classic lymphocytic interstitial pneumonitis (LIP), mucosa-associated lymphoid tissue lymphoma (MALTOMA), or atypical lymphoproliferative disorder (ALD). Immunopathologic results were reviewed when available. RESULTS: Eight patients had AIDS. Five patients had classic LIP. One patient had MALTOMA, and three patients had ALD. Altogether, 2-4-mm-diameter nodules were the predominant CT finding in eight patients; these were peribronchovascular in four patients. The presence of interstitial nodules correlated with the pathologic finding of nodular disease in seven patients. CONCLUSION: Familiarity with these AIDS-related disorders and their CT appearance should assist in the differential diagnosis.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Cytomegalovirus pneumonitis: spectrum of parenchymal CT findings with pathologic correlation in 21 AIDS patients.

PURPOSE: To identify characteristic features of cytomegalovirus (CMV) pneumonitis at computed tomography (CT), particularly markers that may help differentiate CMV from Pneumocystis carinii pneumonia. MATERIALS AND METHODS: Bronchoalveolar lavage (BAL) and biopsy results in 21 patients with acquired immunodeficiency syndrome, cytopathologic evidence of CMV infection without other infections, and available CT scans were retrospectively evaluated. CT findings were correlated with radiographic and pathologic findings when available. RESULTS: BAL findings were positive for CMV in only six cases, 13 patients had extrathoracic CMV infection, and 10 had Kaposi sarcoma. CT findings included ground-glass attenuation, dense consolidation, bronchial wall thickening or bronchiectasis, and interstitial reticulation without air-space disease (12 patients had discrete pulmonary nodules or masses). Biopsy revealed air-space disease as the dominant process in eight cases. Histopathologic findings correlated well with CT appearances. CONCLUSION: CMV pneumonitis should be suspected in patients with either extrathoracic CMV or documented Kaposi sarcoma, especially when radiographic or CT evidence of pulmonary nodules or masses exists.

AIDS-Related Opportunistic Infections↗
PubMed1993

Bronchiectasis: CT evaluation.

CT is the imaging method of choice after standard chest radiography for examining patients with suspected bronchiectasis. In most institutions throughout the world, CT has largely eliminated the need for bronchography in the diagnosis of bronchiectasis. Nonetheless, controversy persists concerning the overall accuracy of CT. In an effort to improve overall diagnostic accuracy, we review the wide range of CT appearances of this protean disorder, and emphasize potential problems and technical pitfalls that may arise in routine clinical imaging.

Bronchiectasis↗
PubMed1992

The left atrial catheter: its uses and complications.

The authors describe the radiographic appearance of the left atrial catheter, a widely used postsurgical intracardiac device. Recognition of the characteristic appearance of this catheter should be of value in detection of potential complications, including line fracture with resultant retention and/or embolization, infection, prosthetic valve dysfunction, and even cardiac tamponade.

Aged↗
PubMed1991

Cystic fibrosis: scoring system with thin-section CT.

The progression of lung disease in patients with cystic fibrosis (CF) was evaluated with chest radiography. The severity and extent of the various radiographic changes were scored with the Chrispin or the Birmingham method, which involves the use of imprecise and subjective terms, such as line shadows, large pulmonary shadows, and nodular cystic lesions. Although computed tomography (CT) has been shown to be helpful in the evaluation of lung disease in CF, no scoring system or other objective criteria have been developed for the evaluation of the wide range of pulmonary changes in these patients. A CT scoring system was devised that incorporates all of the changes seen in the lungs of patients with CF. Such a scoring system may facilitate objective evaluation of existing and newly developed therapeutic regimens and may be a valuable tool in the preoperative evaluation of patients being considered for lobectomy or bullectomy and in the selection of patients for lung transplantation.

Adolescent↗
PubMed1991

Imaging of the intensive care unit patient.

Despite advances in "high tech," it is anticipated that plain chest film radiography will continue to play a significant role in the management of patients in the ICU. Digital radiography will most likely displace conventional approaches. As demonstrated throughout this article, CT has played an increasingly important role in the evaluation of the critically ill patient. The results are especially impressive, because most were obtained on earlier-generation CT machines, which are now totally outdated. Newer scanners have many technical improvements, including rapid scanning, which permits breathholding, and thin-section scanning, which has been discussed in great detail throughout this volume. Whether MR imaging will play an important role in ICU care remains to be determined.

Catheterization↗
PubMed1990

Lung hernia: radiographic features.

Lung hernia is an abnormal protrusion of the lung beyond the confines of the thoracic cage. Hernias are classified as cervical, intercostal, or diaphragmatic. Each of these types can be either congenital or acquired. Acquired hernias can be spontaneous, posttraumatic, or pathologic as a result of a neoplastic or inflammatory process. This report describes five cases of lung hernias. Two were congenital cervical hernias, detected as incidental findings on chest radiographs of infants. One was a posttraumatic intercostal hernia detected on a chest radiograph and confirmed with CT. The remaining two were acquired intercostal hernias at the site of prior chest-tube drainage of tuberculous empyemas. Although both of these were clearly shown on CT scans, only one was visible on chest radiographs.

Aged↗
PubMed1986

The Hermansky-Pudlak syndrome: radiographic features.

We present the radiologic features of four patients proven to have Hermansky-Pudlak syndrome. All four patients had evidence of pulmonary involvement characterized by a progressive, diffuse, bilateral interstitial fibrosis. Extensive bullous changes were seen in one patient. Two patients with evidence of diffuse colitis exhibited an asymmetrical pattern of focal, superficial, and deep ulcerations similar to that of Crohn's disease. The association of these radiographic abnormalities with albinism, ocular abnormalities, bleeding diathesis, and Puerto Rican ancestry establishes the diagnosis.

Adult↗
PubMed1984

Fibrobullous disease of the upper lobes: an extraskeletal manifestation of ankylosing spondylitis.

Fibrobullous disease of the upper lobes of the lungs is a rare extraskeletal manifestation of ankylosing spondylitis, occurring in 1.3% of patients with ankylosing spondylitis. We present a patient with this disease, and discuss this pulmonary manifestation. Because the radiographic appearance of the chest in this disease resembles that in tuberculosis, many patients are misdiagnosed and treated for tuberculosis despite negative bacteriology. Computed tomography is useful in delineating the extent of pleural thickening, bullous changes, volume loss, parenchymal fibrosis, and bronchiectasis, as well as identifying or excluding an intracavitary pulmonary mycetoma.

Adult↗
PubMed1983

The use of computed tomography in evaluating chest wall pathology.

Forty-nine patients with chest wall lesions were evaluated by computed tomography (CT) and conventional radiography. Computed tomography was found to be indispensable for detecting and precisely localizing these lesions. It revealed unsuspected bone destruction and lung, pleural, and mediastinal involvement, as well as invasion of the spinal canal. In more than two thirds of the patients, CT provided additional information of clinical importance in management and, in one third, treatment was altered or the surgical approach modified because of the CT findings. Computed tomography is an essential diagnostic modality in evaluating chest wall lesions.

Adolescent↗
PubMed1983

Computed tomography of lobar collapse: 1. Endobronchial obstruction.

The computed tomographic (CT) appearance of lobar collapse has yet to be defined. In an attempt to determine the characteristic appearance of collapse 95 cases were reviewed retrospectively in a wide variety of clinical settings over a 3 year period ending January 1983. In this report 38 cases of lobar collapse secondary to endobronchial occlusion are analyzed; the appearance of collapse without endobronchial obstruction forms the basis of a subsequent report. Computed tomography was accurate in determining the site of bronchial occlusion in all cases. In 36 of 38 cases collapse was caused by endobronchial tumors, including bronchogenic carcinoma, bronchial carcinoids, endobronchial metastases, and lymphoma. Differentiation between these tumors was not feasible with CT. Most cases of collapse were caused by central tumor. In those cases in which a bolus of contrast material was used differentiation between tumor mass and collapsed pulmonary parenchyma was possible. Two of 38 cases were found to have benign bronchial occlusion. In one case a mucous plug obstructing the left lower lobe bronchus was accurately defined. In another case a bronchial stricture occluded the right lower lobe bronchus. This represented the only false positive case in this series. It is concluded that CT is an accurate means for establishing the diagnosis of endobronchial obstruction. In most cases the diagnosis of neoplasia was possible, provided a bolus of contrast material was used to define tumor mass. The potential role of CT in evaluating patients with lobar collapse is discussed.

Adenocarcinoma↗
PubMed1983

Computed tomography of lobar collapse: 2. Collapse in the absence of endobronchial obstruction.

The computed tomographic appearance of collapse without endobronchial obstruction is reviewed. These 57 cases were classified by the etiology of collapse. The largest group consisted of 29 patients with passive atelectasis, i.e., collapse secondary to fluid, air, or both in the pleural space. Twenty-three of 29 proved secondary to malignant pleural disease. Computed tomography accurately predicted a malignant etiology in 22 of 23 cases. The second largest group of patients had lobar collapse secondary to cicatrization from chronic inflammation. In all cases the underlying etiology was tuberculosis. Radiation caused adhesive atelectasis in six patients secondary to a lack of production of surfactant. In each case a sharp line of demarcation could be defined between normal and abnormal collapsed pulmonary parenchyma. Three cases of unchecked tumor growth caused a peripheral form of collapse (replacement atelectasis). This form of collapse was characterized by an absence of endobronchial obstruction and extensive tumor not delineated by the normal boundaries of the pulmonary lobes.

Cicatrix↗