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G Gamsu

Publications and source records attributed to G Gamsu.

At least 19 recordsLinked to original sources
PubMed2001

A consensus statement of the Society of Thoracic Radiology: screening for lung cancer with helical computed tomography.

This consensus statement by the Society of Thoracic Radiology is a summary of the current understanding of low dose computed tomography (CT) for screening for lung cancer. Lung cancer is the most common fatal malignancy in the industrialized world. Unlike the next three most common cancers, screening for lung cancer is not currently recommended by cancer organizations. Improvements in CT technology make lung screening feasible. Early prevalence data indicate that about two-thirds of lung cancers that are detected by CT screening are at an early stage. Other data support the postulate that patients with lung cancers detected at this early stage have better rates of survival. Whether this will translate into an improved disease specific mortality is yet to be demonstrated. The suggested technical protocols, selection criteria, and method of handling the numerous benign nodules that are detected are discussed. It is the consensus of this committee that mass screening for lung cancer with CT is not currently advocated. Suitable subjects who wish to participate should be encouraged to do so in controlled trials, so that the value of CT screening can be ascertained as soon as possible.

Humans↗
PubMed2000

Optimization of combined CT pulmonary angiography with lower extremity CT venography.

OBJECTIVE: We wanted to determine the time delay for maximum enhancement of the deep venous system of the lower extremities after standard CT pulmonary angiography. SUBJECTS AND METHODS: In 20 patients who had undergone standard CT pulmonary angiography, we measured arterial and venous enhancement at the level of the greater trochanter. These measurements were obtained at 30-sec intervals immediately after completion of CT pulmonary angiography. Ten measurements were obtained in 5 min. Time-density curves were plotted. RESULTS: We found that the median and average peak venous enhancements were 92 and 95 H, respectively. Time to peak enhancement was variable. Because of the broad shape of the venous time-density curve, near peak enhancement could be achieved in most patients at 2 min after CT pulmonary angiography. CONCLUSION: CT of the deep venous system of the lower extremities after standard CT pulmonary angiography, performed with appropriate timing considerations, allows near maximal enhancement of the venous system in most patients without altering the optimum CT pulmonary angiography protocol.

Female↗
PubMed1999

Parenchymal and pleural findings in patients with and patients without acute pulmonary embolism detected at spiral CT.

PURPOSE: To compare the frequencies of parenchymal abnormalities and pleural effusions in patients with and patients without acute pulmonary embolism (PE) detected at spiral computed tomography (CT). MATERIALS AND METHODS: Contrast material-enhanced spiral CT scans obtained in 92 patients clinically suspected of having acute PE were retrospectively reviewed. The presence or absence of parenchymal abnormalities and pleural effusions was noted. The presence of filling defects consistent with central or peripheral PE was recorded. RESULTS: Twenty-eight patients had CT evidence of PE. Central emboli were evident in 27 (96%) of these patients; 23 (82%) had concomitant central and peripheral emboli, and four (14%) had only central emboli. One patient had an isolated subsegmental clot. Parenchymal abnormalities were seen in 24 (86%) patients with PE and 56 (88%) patients without PE. Atelectasis, the most common finding, was present in 20 (71%) patients with PE and 41 (64%) patients without PE. The only parenchymal abnormality significantly associated with PE was peripheral wedge-shaped opacity, which was seen in seven (25%) patients with PE and three (5%) patients without PE (odds ratio, 6.78; 95% CI = 1.60, 28.62). Pleural effusions were seen in 16 (57%) patients with PE and 36 (56%) patients without PE. In 25 (39%) patients without PE, there were additional CT findings that might suggest an alternative explanation for the acute clinical presentation. CONCLUSION: Parenchymal and pleural findings at CT are of limited value for differentiating patients with PE from those without PE.

Acute Disease↗
PubMed1997

High-resolution CT in the evaluation of clinically suspected Pneumocystis carinii pneumonia in AIDS patients with normal, equivocal, or nonspecific radiographic findings.

OBJECTIVE: We prospectively studied AIDS patients with a high clinical pretest probability of Pneumocystis carinii pneumonia (PCP) in whom chest radiographic findings were normal, equivocal, or nonspecific with high-resolution CT (HRCT) to determine the incidence of PCP in these patients, to assess the diagnostic accuracy of HRCT for the presence or absence of PCP, to evaluate the role of HRCT in patient management, and to determine the clinical outcome of all patients 1 month after evaluation. SUBJECTS AND METHODS: All patients were referred to the Division of Pulmonary and Critical Care Medicine for diagnosis of clinically suspected PCP. Thirty-three patients were prospectively evaluated with HRCT within 24 hr of diagnostic bronchoalveolar lavage; 18 other patients who underwent HRCT were managed according to the HRCT interpretation and followed up clinically. All HRCT scans were independently reviewed by three chest radiologists; patchy or nodular ground-glass attenuation was considered to indicate "possible PCP." RESULTS: The incidence of PCP was 12% (6/51). The sensitivity of HRCT was 100%; specificity, 89%; and accuracy, 90% (p < .005). We had five false-positive and no false-negative interpretations. Some form of "airways disease" (n = 23) was the single most common HRCT interpretation. CONCLUSION: HRCT may allow exclusion of PCP in patients with findings that are normal, equivocal, or nonspecific on chest radiographs. Empiric therapy or immediate bronchoscopy can be avoided in many patients on the basis of the HRCT findings.

AIDS-Related Opportunistic Infections↗
PubMed1996

High-resolution computed tomography of airway changes after induced bronchoconstriction and bronchodilation in asthmatic volunteers.

RATIONALE AND OBJECTIVES: We examined whether high-resolution computed tomography (HRCT) would detect and quantify induced airway changes in asthmatic volunteers. METHODS: We performed pulmonary function tests and HRCT on eight asthmatic adults and two nonasthmatic control adults under three conditions: baseline, after methacholine inhalation, and after albuterol inhalation. Changes in pulmonary function, airway internal luminal diameter (AILD), and airway wall thickness (AWT) in the three conditions were compared. RESULTS: After methacholine inhalation, pulmonary function showed significant airflow obstruction in the asthmatic volunteers compared with two nonasthmatic control volunteers. The median value for AILD decreased by 17% (p = .04). After subsequent inhalation of albuterol, pulmonary function improved to above the baseline levels in the eight asthmatic volunteers. The median value for AILD increased by 18% above the baseline value (p = .001). No changes in pulmonary function or AILD were seen in the two nonasthmatic volunteers. AWT did not change significantly in either the asthmatic or nonasthmatic volunteers after inhalation of methacholine or albuterol. CONCLUSION: HRCT can quantify changes in the internal luminal diameter of asthmatic airways provoked by methacholine and albuterol inhalation.

Adult↗
PubMed1996

Pulmonary tuberculosis: comparison of CT findings in HIV-seropositive and HIV-seronegative patients.

PURPOSE: To determine the differences in the computed tomographic (CT) appearance of pulmonary tuberculosis (TB) between patients with and patients without human immunodeficiency virus (HIV) infection. MATERIALS AND METHODS: CT scans and chest radiographs of 42 HIV-seropositive and 42 HIV-seronegative patients with pulmonary TB were reviewed. CD4 T-lymphocyte counts, measured in 40 seropositive patients, were at least 200 cells per microliter in 10 patients and were less that 200 cells per microliter in 30. RESULTS: Seropositive patients had a higher prevalence of lymphadenopathy at chest radiography (P< .05). The seropositive patients had a lower prevalence of consolidation (P< .05), cavitation (P< .01), and postprimary pattern (P< .05) at CT. HIV-seropositive patients had a higher frequency of miliary (P< .01) and extrapulmonary disease (P< .001). Similar features of pulmonary TB were observed in seropositive patients with mild and severe immunosuppression. CONCLUSION: HIV-seropositive patients had a lower prevalence of localized parenchymal disease and a higher prevalence of disseminated disease at CT.

AIDS-Related Opportunistic Infections↗
PubMed1996

Causes of pulmonary impairment in asbestos-exposed individuals with diffuse pleural thickening.

To examine whether diffuse pleural thickening (DPT) causes impairment of pulmonary function independent of other manifestations of asbestos-related disease, we studied individuals selected from 1,150 men with occupational asbestos exposure who had undergone pulmonary function testing and computed tomographic (CT) scanning. The CT scans revealed 84 subjects with DPT as defined for CT. Of these 84 subjects, 53 eligible study cases were matched by age with a referent group without DPT from the same exposed group. No difference was demonstrated between cases and referents in smoking history, length of exposure, latency, or the proportion with either interstitial fibrosis or pleural plaques. Individuals with DPT demonstrated significantly reduced forced vital capacity (FVC) (p = 0.002) and diffusing capacity for carbon monoxide (DLCO) (p = 0.002) as compared with the referents. No difference was found in the two groups' FEV1 to FVC ratio (FEV1/FVC). Individuals with DPT and either interstitial fibrosis or pleural plaques showed a significantly lower FVC than did those with fibrosis or pleural plaques alone. Individuals with DPT and rounded atelectasis had similar pulmonary function to those with DPT and no rounded atelectasis. Subjects with DPT had a more frequent history of coronary bypass surgery than referents (19% versus 2%; p = 0.008). We conclude that subjects with DPT have restrictive pulmonary function and reduced diffusing capacity independent of other manifestations of asbestos-related disease.

Aged↗
PubMed1996

Artifacts in chest radiographs with a third-generation computed radiography system.

Photostimulable phosphor computed radiography (CR) is a developing and increasingly widespread technology. The purpose of this pictorial essay is to familiarize readers with the appearance and cause of image artifacts that can occur in a third-generation computed radiographic system. Artifacts are described that relate to imaging plates, image readers, image processing, and film processing.

Adult↗
PubMed1995

High-resolution computed tomography sampling for detection of asbestos-related lung disease.

RATIONALE AND OBJECTIVES: We determined whether a limited number of high-resolution computed tomography (HRCT) scans will effectively screen for interstitial lung disease (ILD) in a population of individuals exposed to asbestos. METHODS: We retrospectively reviewed the computed tomography studies of 49 patients exposed to asbestos. HRCT in the supine and prone positions had been performed at specifically preselected levels. Two teams of thoracic radiologists evaluated, on separate occasions: (1) all images, (2) prone images only, and (3) a single prone image through the lung bases for the presence of diffuse ILD. RESULTS: A relatively high level of accuracy was obtained with a single prone scan. However, improvement to 95% or better was found when additional prone images were used. CONCLUSION: A screening study for ILD, in this case patients exposed to asbestos, may be performed by preselected prone HRCT images only. The ease and decreased time of performing the procedure make screening relatively large patient groups for ILD more feasible.

Asbestos↗
PubMed1995

AIDS-related Kaposi sarcoma of the lung: radiographic findings and staging system with bronchoscopic correlation.

PURPOSE: To determine the chest radiographic findings in patients with tracheobronchial Kaposi sarcoma (KS) and to develop a radiographic staging system that allows comparison of radiographic to bronchoscopic findings and allows assessment of the typical temporal progression of pulmonary KS. MATERIALS AND METHODS: The chest radiographs and medical records of 76 male patients, aged 23-60 years (mean, 36 years 4 months) with bronchoscopically proved KS were retrospectively reviewed. Tumor extent at bronchoscopy (grade 1-3) was compared with severity of parenchymal disease (radiographic stage 0-3). RESULTS: There was a statistically significant relationship between extent of tracheobronchial disease and radiographic stage (P = .01). However, in some patients, parenchymal KS of advanced stage was present with no visible endobronchial disease. CONCLUSION: The proposed staging system describes features of early, moderate, and advanced KS. Although there is a correlation between tracheobronchial and parenchymal disease, the latter can occur in the absence of endobronchial lesions.

Acquired Immunodeficiency Syndrome↗
PubMed1995

CT quantification of interstitial fibrosis in patients with asbestosis: a comparison of two methods.

OBJECTIVE: The likelihood of interstitial lung disease being detected on high-resolution CT scans and having functional significance is often related to the severity of the disease. The extent and severity of the abnormalities seen on high-resolution CT are usually assessed subjectively. This study was undertaken to investigate whether a subjective semiquantitative scoring method or a method using a cumulation of the different high-resolution CT features of asbestosis were comparable in suggesting asbestosis in a group of patients with histopathologic confirmation of disease. A secondary objective was to compare the results of these two high-resolution CT methods with chest radiographs in the same population. MATERIALS AND METHODS: This study group consisted of 24 patients and six lungs obtained at autopsy. Histopathologic asbestosis was present in 25 of the 30 patients or lungs. The patients or lungs were imaged using selected high-resolution CT scans. The high-resolution CT scans were assessed in two ways. One used a subjective semiquantitative extent and severity score consisting of four levels of severity, while the other was a cumulative score adding the different types of high-resolution abnormalities in asbestosis. The commonest high-resolution CT abnormalities in the cases with confirmed asbestosis were interstitial lines (84%), parenchymal bands (76%), and architectural distortion of secondary pulmonary lobules (56%). Subpleural lines and honeycombing were less frequent. The histopathologic severity of asbestosis was independently graded on a four-point scale. Chest radiographs, when available, were classified according to the International Labor Organization (ILO) classification of pneumoconioses. RESULTS: With the subjective semiquantitative high-resolution CT severity score, asbestosis was suggested in 16 (64%) instances, all with disease. With the cumulative method, any one type of abnormality was present in 88% of cases with asbestosis, two types in 78%, and three in 56%. However, to include only cases with asbestosis, three different abnormalities had to be present. The high-resolution CT scans were normal or near normal in five instances of asbestosis. Chest radiographs using the ILO classification predicted asbestosis with a lesser frequency than high-resolution CT in this selected population. CONCLUSION: We conclude that a subjective semiquantitative grading system of the extent and severity of asbestosis and a method using a cumulative addition of the different findings in asbestosis give similar results in suggesting the presence of disease. Thus, for the high-resolution CT detection of asbestosis, a combination of the cumulative number of different findings and an assessment of the extent and severity of the abnormalities could be complimentary. We also conclude that asbestosis can be present histopathologically with a normal or near normal high-resolution CT scan.

Aged↗
PubMed1995

Dyspnea in ambulatory patients with SLE: prevalence, severity, and correlation with incremental exercise testing.

OBJECTIVE: We sought to determine the prevalence and severity of dyspnea, and to correlate dyspnea with clinical features and exercise limitation in ambulatory patients with systemic lupus erythematosus (SLE). METHODS: Twenty-five consecutive patients were evaluated with a validated pulmonary questionnaire, chest radiograph, 2-dimensional echocardiography, resting pulmonary function tests, and incremental exercise testing. RESULTS: Dyspnea was reported by 60% (95% CI 39-79) of patients; 20% (95% CI 7-40) had severe dyspnea (inability to dress without dyspnea) and 12% (95% CI 3-31) had moderate dyspnea (dyspnea after walking 100 yards). Compared to patients without dyspnea, patients with dyspnea were more likely to have had a history of clinical lupus involving the lung (80 vs 40%, p = 0.05), a lower total lung capacity (77.5 vs 94.8%, p = 0.002), and a reduced maximum oxygen consumption (VO2max of 53.4 vs 67.7%, p = 0.01). Patients with severe dyspnea and patients without dyspnea did not differ in duration of prednisone use, activity of disease, weight, or in frequency of Raynaud's phenomenon (p > 0.05). Only 4% of all patients had abnormal left ventricular motion on 2-dimensional echo; patients with moderate or severe dyspnea had normal left ventricular motion. Of the 5 patients with severe dyspnea, 4 (80%) had restrictive lung disease and 1 (20%) had an isolated diffusion defect. All patients with dyspnea had an abnormal exercise test, but so did 9/10 without dyspnea (p > 0.05). Severity of dyspnea correlated highly with maximum exercise tolerance measured by VO2max (R2 = 0.51, p = 0.0001). CONCLUSION: In ambulatory patients with SLE, dyspnea is common, frequently disabling, associated with a history of lupus involvement of the lung, and correlates highly with objective measures of exercise limitation.

Adult↗
PubMed1994

Chronic pulmonary disorders in sickle cell disease: findings at thin-section CT.

PURPOSE: To characterize the non-acute abnormalities seen at computed tomography (CT) in patients with sickle cell (SC) disease and a prior history of acute chest syndrome (ACS)-pneumonia. MATERIALS AND METHODS: Twenty-nine patients with SC disease who had experienced one to more than 10 (median, six) previous episodes of ACS-pneumonia were prospectively studied with thin-section CT of the thorax. Scans were graded for interstitial disease and assigned a disease index ranging from 0 to 3. Twenty-four patients underwent pulmonary function tests (PFTs) and measurement of their blood gasses. RESULTS: Twelve of the 29 patients (41%) had significant interstitial disease that was multifocal. A correlation was found between the disease index and number of episodes of ACS-pneumonia (P = .02) but not between the disease index and PFT results. CONCLUSION: Thin-section CT demonstrates significant multifocal interstitial lung abnormalities in 41% of selected patients with SC disease. The pattern is most consistent with scarring from episodes of infarction or infection.

Acute Disease↗
PubMed1994

Pulmonary aspergillosis: imaging findings with pathologic correlation.

Pulmonary involvement with Aspergillus fumigatus is varied and largely dependent on the patient's underlying pulmonary and immune status. Hypersensitivity reactions from inhalation of spores can cause acute allergic alveolitis, and bronchial colonization can cause allergic bronchopulmonary aspergillosis (ABPA). The latter is found mainly in patients with asthma or cystic fibrosis. Mycetomas develop from secondary colonization of preexisting lung cavities. Invasive and semi-invasive aspergillosis affect mostly patients with altered immune status. This essay illustrates the radiologic findings of pulmonary aspergillosis and shows the correlation between the imaging and pathologic findings.

Aspergillosis↗
PubMed1994

Dynamic quantitative computed tomography. A predictor of pulmonary function in obstructive lung diseases.

RATIONALE AND OBJECTIVES: Nine patients were examined using dynamic electron beam computed tomography to assess the utility of this technique in detecting airway obstruction and air trapping, and to compare this technique with pulmonary physiologic testing. METHODS: Dynamic computed tomography (C-100 Ultrafast CT scanner, Imatron, Inc., South San Francisco, CA) was performed, with a series of ten, 100-msec images obtained in a 6-second period during forced inhalation and exhalation. Time-attenuation curves were calculated from the observed changes in lung attenuation. Estimates of the percentage of each lung that showed air trapping were made at each level scanned, using a 5-point scale. Specific correlations were made for pulmonary function test results and air-trapping score. RESULTS: In all nine patients, dynamic computed tomography demonstrated one or more sites that failed to show a normal increase in lung attenuation during forced exhalation. Four of these 9 patients showed a paradoxical decrease in lung attenuation during exhalation in at least one region of the lung. Extent of air-trapping correlated well with forced expiratory volume in one second (r = -.92). CONCLUSIONS: Based on this small sample, the authors believe that this technique will prove sensitive for detecting abnormalities of ventilation and may be a useful adjunct to conventional diagnostic procedures in the management of disorders of airway obstruction.

Adult↗