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Nestor L Müller

Publications and source records attributed to Nestor L Müller.

At least 19 recordsLinked to original sources
PubMed2007

Dynamic MRI of solitary pulmonary nodules: comparison of enhancement patterns of malignant and benign small peripheral lung lesions.

OBJECTIVE: The purpose of this study was to compare the dynamic contrast-enhanced MRI enhancement characteristics of malignant and benign solitary pulmonary nodules. MATERIALS AND METHODS: The characteristics of 202 solitary pulmonary nodules (diameter, 1-3 cm; 144 cases of primary lung cancer, 31 cases of focal organizing pneumonia, 15 tuberculomas, 12 hamartomas) were reviewed retrospectively. In all cases dynamic MR images were obtained before and 1, 2, 3, 4, 5, 6, and 8 minutes after bolus injection of gadopentetate dimeglumine. Maximum enhancement ratio, time at maximum enhancement ratio, slope of time-enhancement ratio curves, and washout ratio were assessed. Statistical analyses were performed with the Kruskal-Wallis test with Bonferroni correction, chi-square test, and receiver operating characteristic curves. RESULTS: For 122 (85%) of 144 primary lung cancers, time at maximum enhancement ratio was 4 minutes or less. For all tuberculomas and hamartomas, time at maximum enhancement ratio was greater than 4 minutes or gradual enhancement occurred without a peak time (p < 0.0001). Lung cancers had different maximum enhancement ratios and slopes than benign lesions (all p < 0.005). With 110% or lower maximum enhancement ratio as a cutoff value, the positive predictive value for malignancy was 92%; sensitivity, 63%; and specificity, 74%. With 13.5%/min or greater slope as a cutoff value, sensitivity, specificity, positive predictive value, and negative predictive value for malignancy were 94%, 96%, 99%, and 74%, respectively. CONCLUSION: Dynamic contrast-enhanced MRI is helpful in differentiating benign from malignant solitary pulmonary nodules. Absence of significant enhancement is a strong predictor that a lesion is benign.

Adult↗
PubMed2006

Usual interstitial pneumonia and chronic idiopathic interstitial pneumonia: analysis of CT appearance in 92 patients.

PURPOSE: To retrospectively analyze computed tomographic (CT) findings of chronic idiopathic interstitial pneumonia (IIP) and to determine which findings are most helpful for distinguishing IIP from usual interstitial pneumonia (UIP) with univariate and multivariate analyses. MATERIALS AND METHODS: Institutional review board approval and informed consent were not required for this retrospective review of patient records and images. Two observers working independently and without knowledge of the diagnosis evaluated the extent and distribution of various thin-section CT findings (ground-glass opacity, consolidation, reticulation, and honeycombing) in 92 patients (51 men, 41 women; mean age, 56 years; age range, 29-81 years) with a histologic diagnosis of UIP (n = 20), cellular nonspecific interstitial pneumonia (NSIP) (n = 16), fibrotic NSIP (n = 16), respiratory bronchiolitis-associated interstitial lung disease (RB-ILD) (n = 11), desquamative interstitial pneumonia (DIP) (n = 15), or lymphoid interstitial pneumonia (LIP) (n = 14). Observers used univariate and multivariate statistical analyses to compare their findings with the extent and distribution of UIP. RESULTS: Observers made the correct diagnosis in 145 (79%) of 184 readings. Multivariate logistic regression analysis showed that the independent findings that distinguished UIP from cellular NSIP were the extent of honeycombing and the most proximal bronchus with traction bronchiectasis (odds ratio, 5.16 and 0.37, respectively); the finding that distinguished UIP from fibrotic NSIP was the extent of honeycombing (odds ratio, 2.10). CT features that distinguished UIP from RB-ILD and DIP included extent of ground-glass opacity (odds ratio, 0.76), thickening of bronchovascular bundles (odds ratio, 1.58), the most proximal bronchus with traction bronchiectasis (odds ratio, 0.22), and the number of segments with traction bronchiectasis (odds ratio, 3.64). CONCLUSION: UIP has a characteristic appearance that usually facilitates distinction from other types of chronic IIPs at thin-section CT. The most useful finding when differentiating UIP from NSIP was the extent of honeycombing.

Adult↗
PubMed2006

Thymic epithelial tumors: comparison of CT and MR imaging findings of low-risk thymomas, high-risk thymomas, and thymic carcinomas.

OBJECTIVE: To assess the CT and magnetic resonance (MR) imaging findings of thymic epithelial tumors classified according to the current World Health Organization (WHO) histologic classification and to determine useful findings in differentiating the main subtypes. MATERIALS AND METHODS: Sixty patients with thymic epithelial tumor who underwent both CT and MR imaging were reviewed retrospectively. All cases were classified according to the 2004 WHO classification. The following findings were assessed in each case on both CT and MRI: size of tumor, contour, perimeter of capsule; homogeneity, presence of septum, hemorrhage, necrotic or cystic component within tumor; presence of mediastinal lymphadenopathy, pleural effusion, and great vessel invasion. These imaging characteristics of 30 low-risk thymomas (4 type A, 12 type AB, and 14 type B1), 18 high-risk thymomas (11 type B2 and seven type B3), and 12 thymic carcinomas on CT and MR imaging were compared using the chi-square test. Comparison between CT and MR findings was performed by using McNemar test. RESULTS: On both CT and MR imaging, thymic carcinomas were more likely to have irregular contours (P < .001), necrotic or cystic component (P < .05), heterogeneous contrast-enhancement (P < .05), lymphadenopathy (P < .0001), and great vessel invasion (P < .001) than low-risk and high-risk thymomas. On MR imaging, the findings of almost complete capsule, septum, and homogenous enhancement were more commonly seen in low-risk thymomas than high-risk thymomas and thymic carcinomas (P < .05). MR imaging was superior to CT in the depiction of capsule, septum, or hemorrhage within tumor (all comparison, P < .05). CONCLUSION: The presence of irregular contour, necrotic or cystic component, heterogeneous enhancement, lymphadenopathy, and great vessel invasion on CT or MR imaging are strongly suggestive of thymic carcinomas. On MR imaging, the findings of contour, capsule, septum, and homogenous enhancement are helpful in distinguishing low-risk thymomas from high-risk thymomas and thymic carcinomas.

Adult↗
PubMed2006

Drug-induced lung diseases: most common reaction patterns and corresponding high-resolution CT manifestations.

Drug-induced lung disease is an increasingly common cause of morbidity and mortality. The diagnosis is based on clinical history and consistent radiologic findings. Lung biopsy is performed in a small percentage of cases. High-resolution CT may demonstrate parenchymal abnormalities in patients with normal radiographs and provides a better depiction of the pattern and distribution of findings. Knowledge of the most common high-resolution CT manifestations and the corresponding histologic patterns is important for early recognition and proper management of drug-induced lung disease.

Diagnosis, Differential↗
PubMed2006

Pleural plaques in asbestos-exposed workers: reproducibility of a new high-resolution CT visual semiquantitative measurement method.

OBJECTIVE: To assess the reproducibility of a new high-resolution computed tomography (CT) visual semiquantitative method for pleural plaques in asbestos-exposed workers. MATERIAL AND METHODS: We performed thin-section CT in 752 chrysotile asbestos mining workers and ex-workers. Institutional review board approval and signed written informed consent from subjects were obtained. Two readers independently evaluated the 752 CT scans and identified 57 workers (mean age +/- SD, 61.8 years +/- 8.1; range, 37 to 81 years) who had pleural plaques and no other pleural or parenchymal abnormality. Three independent radiologists then quantified the plaque burden in these 57 workers using a scoring system based on the evaluation of the maximum thickness of parietal pleural plaques and percentage of parietal pleural surface involvement. We also calculated the proportion between the number of CT slices with diaphragmatic plaques and the total number of slices in which the diaphragm was seen (pdiaph). The intraobserver and interobserver agreements were analyzed using weighted Kappa coefficient. RESULTS: Interobserver agreements were good for the pleural plaque score (k = 0.61, 0.75, and 0.79) and ranged from good (k = 0.61) to excellent (k = 0.86) for the pdiaph. Intraobserver agreements ranged from good to excellent for the pleural plaque score (k = 0.79 and 1.00) and for the pdiaph (k = 0.79 and 0.93). CONCLUSION: The method proposed for high-resolution CT pleural plaque quantification in asbestos-exposed workers has a high reproducibility.

Adult↗
PubMed2006

Drug-associated organizing pneumonia: high-resolution CT findings in 9 patients.

OBJECTIVE: To assess the high-resolution computed tomography appearances of drug-associated organizing pneumonia (OP). MATERIALS AND METHODS: Nine patients with clinical and biopsy proven drug-associated OP were included in the study. High-resolution computed tomography exams were retrospectively reviewed by 2 observers for the presence, extent, and distribution of parenchymal abnormalities. RESULTS: The commonest findings consisted of air space consolidation (n = 8) and ground-glass opacification (n = 7). The air space consolidation was bilateral and asymmetric in 7 patients, symmetric in 1 patient and in all cases involved mainly the peribronchial or subpleural regions or both. The ground-glass opacities were predominantly bilateral and asymmetric in 6 patients and unilateral in 1 patient. They had a patchy distribution in 4 patients, were diffuse in 2 patients, and subpleural in 1 patient. CONCLUSION: Drug-associated OP most commonly presents with bilateral, asymmetrical air space consolidation in a predominantly peribronchial and subpleural distribution.

Adult↗
PubMed2006

Pulmonary invasive aspergillosis and candidiasis in immunocompromised patients: a comparative study of the high-resolution CT findings.

The purpose of this study was to compare the high-resolution computed tomography (HRCT) findings of pulmonary invasive aspergillosis and candidiasis in immunocompromised patients. The study included 54 immunocompromised patients (32 men, 22 women; 10 to 68 years of age, median 40 years) with a diagnosis of Aspergillus (n=32) or Candida (n=22) pulmonary infection obtained by sputum culture, bronchoalveolar lavage culture, transbronchial biopsy, surgical biopsy, or autopsy. High-resolution CT images were assessed for the presence and distribution of nodules, consolidation and ground-glass opacities. Presence of the CT halo sign and cavitation was also recorded and the overall distribution of abnormalities was assessed. Comparison was made using the Fisher exact test. Nodules were the most common finding, present in 84% (27 of 32) of patients with aspergillosis and 95% (21 of 22) of patients with candidiasis (P>0.3, Fisher exact test). Centrilobular nodules were more common in patients with aspergillosis (26 of 27, 96%) than in those with candidiasis (11 of 21, 52%) (P<0.001) and random nodules more common in candidiasis (10 of 21, 48%) than in aspergillosis (1 of 27, 4%) (P<0.001). Presence of the CT halo sign, cavitation, and ground-glass opacities was similar in both groups. In summary, pulmonary aspergillosis and candidiasis in immunocompromised patients manifest with similar high-resolution CT findings. Centrilobular nodules and consolidation are more common in aspergillosis. The presence of halo sign or cavitation is not helpful in the differential diagnosis.

Adolescent↗
PubMed2006

Diffuse lung cysts in lymphoid interstitial pneumonia: high-resolution CT and pathologic findings.

Lymphoid interstitial pneumonia is part of a spectrum of pulmonary lymphoproliferative disorders that range from benign, small, and airway-centered cellular infiltrates (follicular bronchiolitis, nodular lymphoid hyperplasia) to low-grade malignant lymphoma. Most of the cases occur in patients with underlying autoimmune disease or immunodeficiency. The characteristic high-resolution computed tomography findings consist of diffuse ground-glass opacities, ill-defined centrilobular nodules, bronchovascular thickening, interlobular septal thickening, and scattered thin-walled cysts. The cysts may be seen in up to 80% of the patients and are typically few in number and measure less than 3 cm in diameter. This case illustrates extensive cysts as the predominant high-resolution computed tomography finding of idiopathic lymphoid interstitial pneumonia in a 64-year-old man who underwent unilateral lung transplant. Such extensive cystic disease and lung transplantation treatment has not been previously described.

Cysts↗
PubMed2006

The value of thoracic computed tomography scans in clinical diagnosis: a prospective study.

BACKGROUND: Computed tomography (CT) scans are used extensively to investigate chest disease because of their cross-sectional perspective and superior contrast resolution compared with chest radiographs. These advantages lead to a more accurate imaging assessment of thoracic disease. The actual use and evaluation of the clinical impact of thoracic CT has not been assessed since scanners became widely available. OBJECTIVE: To identify patterns of utilization, waiting times and the impact of CT scan results on clinical diagnoses. DESIGN: A before and after survey of physicians who had ordered thoracic CT scans. SETTING: Vancouver General Hospital--a tertiary care teaching centre in Vancouver, British Columbia. SUBJECTS: Physicians who had ordered CT scans. INTERVENTION: Physicians completed a standard questionnaire before and after the CT scan result was available. MEASUREMENTS: Changes in the clinical diagnosis, estimates of the probabilities for the diagnosis both before and after the CT scan, and waiting times. RESULTS: Four hundred fifty-four thoracic CT cases had completed questionnaires, of whom 80% were outpatients. A change in diagnosis was made in 48% of cases (25% with a normal CT scan and 23% with CT scan findings that indicated a different diagnosis). The largest change in probability scores for the clinical diagnosis before and after the CT scan was 43.9% for normal scans, while it was 36.3% for a different diagnosis and 26.3% for the same diagnosis. High-priority scans were associated with decreased waiting time (--7.89 days for each unit increase in priority). CONCLUSIONS: The CT scan results were associated with a change in diagnosis in 48% of cases. Normal scans constituted 25% of the total and had the greatest impact scores. Waiting times were highly correlated with increased urgency of the presenting problem.

British Columbia↗
PubMed2006

Idiopathic interstitial pneumonias: prevalence of mediastinal lymph node enlargement in 206 patients.

OBJECTIVE: The purposes of our study were to determine the prevalence of mediastinal lymphadenopathy in idiopathic interstitial pneumonias, correlate their presence with high-resolution CT (HRCT) findings, and assess the potential value of mediastinal lymphadenopathy in the differential diagnosis of idiopathic interstitial pneumonias. MATERIALS AND METHODS: The study included 206 consecutive patients from three medical centers with pathologically proven idiopathic pulmonary fibrosis (n = 136), non-specific interstitial pneumonia (NSIP) (n = 47), cryptogenic organizing pneumonia (COP) (n = 16), respiratory bronchiolitis-interstitial lung disease (RB-ILD) (n = 5), and desquamative interstitial pneumonia (DIP) (n = 2). HRCT scans were retrospectively reviewed for the presence of mediastinal lymphadenopathy (short-axis diameter, >or= 10 mm), predominant parenchymal pattern, and extent of disease. RESULTS: Mediastinal lymphadenopathy was seen in 139 (67%) of 206 patients, including 90 (66%) of 136 with idiopathic pulmonary fibrosis, 38 (81%) of 47 with NSIP, six (38%) of 16 with COP, and five (71%) of seven with RB-ILD or DIP. The presence of enlarged nodes was less common in COP than in the other idiopathic interstitial pneumonias (p = 0.04). No significant difference was found in the prevalence of lymphadenopathy in patients with predominant ground-glass opacity (53%) or predominant reticulation (40%). The extent of parenchymal abnormalities was 25-50% in 74 patients (53%), 50-75% in 30 (22%), < 25% in 22 (16%), and > 75% in 13 (9%). A positive correlation between the extent of disease and presence of lymphadenopathy was seen in patients with NSIP (p = 0.01). CONCLUSION: Mediastinal lymphadenopathy is a common feature in idiopathic interstitial pneumonias, being slightly less common in COP than in the other idiopathic interstitial pneumonias. The presence of lymphadenopathy therefore has limited value in the differential diagnosis. In patients with idiopathic pulmonary fibrosis, the presence of lymph node enlargement did not correlate to any specific HRCT pattern or to the extent of disease.

Diagnosis, Differential↗
PubMed2006

High-resolution MDCT of pulmonary septic embolism: evaluation of the feeding vessel sign.

OBJECTIVE: The objective of this study was to use high-resolution MDCT to assess the relation of the pulmonary vasculature to septic emboli with particular attention to the feeding vessel sign. MATERIALS AND METHODS: The MDCT scans of nine patients with septic emboli were retrospectively, blindly evaluated by two observers. A control group of 10 patients with documented pulmonary metastasis and pathologically proven carcinoma also were included. Transverse images, multiplanar reconstructions, and maximum intensity projections were used to analyze nodules and the pulmonary vasculature. The CT scans were obtained with 1- to 1.25-mm collimation on a 4-, 8-, or 16-MDCT scanner. The feeding vessel sign was defined as a vessel coursing directly into a nodule. RESULTS: The patients with septic embolism had a total of 141 nodules and 52 wedge-shaped opacities. Transverse images showed that 52 (37%) of the nodules and 11 (22%) of the wedge-shaped opacities had a vessel that appeared to enter the nodule, but multiplanar reconstructions (without IV contrast enhancement) and maximum intensity projections (with IV contrast enhancement) showed the vessels passed around the nodules. Twenty-one (15%) of the spherical nodules and seven (13%) of the wedge-shaped opacities exhibited a central vessel entering the lesion in all imaging planes. All of these vessels were traced to the left atrium on transverse images, a finding consistent with pulmonary vein branches. Similar findings were seen in pulmonary metastatic lesions. CONCLUSION: Although pulmonary septic emboli often appear to have a feeding vessel on conventional cross-sectional images, multiplanar reconstructions show that most of these vessels course around the nodule and that the others are pulmonary veins.

Adolescent↗
PubMed2006

Conventional high-resolution CT versus helical high-resolution MDCT in the detection of bronchiectasis.

OBJECTIVE: The purpose of this study was to compare conventional high-resolution CT (HRCT) with helical 16-MDCT in the detection of bronchiectasis. MATERIALS AND METHODS: We retrospectively evaluated 80 patients including 61 with bronchiectasis (mean age, 64 years; range, 22-87 years) and a control group of 19 patients with normal MDCT of the chest. Two sets of images were blindly, randomly analyzed by two observers: contiguous 1-mm slices (MDCT set) and 1-mm slices every 10 mm (HRCT set) derived from the MDCT set. Images were scored independently for presence, extent, and severity of bronchiectasis, followed by a consensus interpretation. Kappa analysis assessed inter- and intraobserver agreement. MDCT was the radiologic gold standard. RESULTS: Of the 61 patients with bronchiectasis diagnosed with MDCT, 56 (92%) were positive for bronchiectasis on conventional HRCT. Seven patients had positive MDCT scans only, and two patients had positive HRCT scans only. Of 479 lobes, 59 were positive for bronchiectasis on MDCT and negative on HRCT, and 19 lobes were positive for bronchiectasis on HRCT and negative on MDCT (p < 0.0001). MDCT showed 25 more lobes with cylindric, 11 more lobes with varicose, and four more lobes with cystic bronchiectasis than did HRCT. Sensitivity, specificity, and positive and negative predictive values of HRCT in detecting bronchiectasis were 71%, 93%, 88%, and 81%, respectively. Interobserver agreement for presence, extent, and severity of bronchiectasis ranged from moderate to good for MDCT (kappa values, 0.64, 0.5, and 0.48, respectively) and poor to good for HRCT (kappa values, 0.65, 0.46, and 0.25, respectively). CONCLUSION: Contiguous helical 16-MDCT with 1-mm collimation is superior to HRCT at 10-mm intervals in showing the presence and extent of bronchiectasis.

Adult↗
PubMed2005

Pulmonary candidiasis after hematopoietic stem cell transplantation: thin-section CT findings.

PURPOSE: To retrospectively evaluate thin-section computed tomographic (CT) findings in hematopoietic stem cell transplant (ie, bone marrow transplant) patients with histopathologically proved pulmonary candidiasis. MATERIALS AND METHODS: Ethical approval was obtained from the institutional review board of each of the three institutions; informed consent was not required. The study included 17 hematopoietic stem cell transplant recipients with proved pulmonary candidiasis. Histopathologic specimens were acquired at transbronchial biopsy (n = 8), open lung biopsy (n = 6), and autopsy (n = 3). The patients included seven men and 10 women (age range, 20-62 years; mean age, 37 years). The thin-section CT scans were retrospectively reviewed by two thoracic radiologists for the presence, appearance, and distribution of parenchymal abnormalities. RESULTS: Multiple nodules were present in 15 (88%) patients, including centrilobular nodules and tree-in-bud pattern in seven (41%) patients. Nodules were bilateral in 12 patients and unilateral in three. An associated halo of ground-glass opacity was identified in five (33%) patients. Nodules were the only CT finding in five patients (29%). Areas of air-space consolidation were identified in 11 (65%) patients. Areas of ground-glass opacity were seen in six (35%) of 17 patients and were always associated with other abnormalities. Other less common CT findings included pleural effusion (n = 3), thickening of the bronchial walls (n = 2), and cavitation (n = 1). CONCLUSION: The most common thin-section CT findings of pulmonary candidiasis in hematopoietic stem cell transplant patients are multiple bilateral nodular opacities often associated with areas of consolidation.

Adult↗
PubMed2005

Metabolic lung disease: imaging and histopathologic findings.

Metabolic lung disease includes pulmonary alveolar proteinosis (PAP), pulmonary amyloidosis, metastatic pulmonary calcification, dendritic pulmonary ossification, pulmonary alveolar microlithiasis, and storage diseases. In pulmonary alveolar proteinosis, CT demonstrates air-space consolidation with thickened interlobular septa, producing the so-called "crazy paving" appearance. Pulmonary amyloidosis can appear as parenchymal nodules (nodular parenchymal form), diffuse interstitial deposit (diffuse interstitial form), or submucosal deposits in the airways (tracheobronchial form). Metastatic pulmonary calcification may appear on high-resolution CT as numerous 3- to 10-mm diameter calcified nodules or, more commonly as fluffy and poorly defined nodular opacities. In pulmonary microlithiasis, high-resolution CT demonstrates diffuse punctuate micronodules showing slight perilobular predominance resulting in apparent calcification of interlobular septa. Niemann-Pick disease appears as ground-glass attenuation in the upper lung zone and thickening of the interlobular septa in the lower lung zone. Radiologic study including high-resolution CT will be helpful for the diagnosis and follow-up of these diseases.

Adult↗
PubMed2005

Myeloid leukemias and lung involvement.

Myeloid leukemias are clonal malignancies characterized by the presence of increased numbers of immature myeloid cells in the marrow and peripheral blood. Pulmonary involvement by myeloid leukemia is relatively uncommon and seen mainly in patients with severe disease. The most common form of pulmonary involvement consists of leukemic infiltration along the lymphatics in the peribronchovascular, septal, and pleural interstitial tissue. Less common manifestations include myeloid sarcoma, leukostasis, leukemic cell lysis pneumopathy, and hyperleukocytic reaction. The radiological manifestations of pulmonary leukemic cell infiltration and leukostasis consist mainly of bilateral thickening of the peribronchovascular interstitium and interlobular septa, a pattern that resembles that of interstitial pulmonary edema. The radiological manifestations of leukemic cell lysis pneumopathy and hyperleukocytic reaction consist of symmetric bilateral areas of consolidation. This manuscript reviews the histological and radiological intrathoracic manifestations of myelogenous leukemias.

Diagnosis, Differential↗