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N L Müller

Publications and source records attributed to N L Müller.

At least 19 recordsLinked to original sources
PubMed1992

High-resolution computed tomography of drug-induced lung disease.

In order to determine the potential clinical utility of high-resolution CT (HRCT) in the assessment of drug-induced lung disease, we reviewed the chest radiographs and HRCT scans of 23 patients and five normal controls. The radiographs and HRCT scans were reviewed separately in random order by two independent observers who were not aware of the relative numbers of patients and controls. Abnormal findings were detected in the affected patients in 17/23 radiographs compared to 23/23 HRCT scans. The patients included five cases of bleomycin toxicity, five cases of nitrofurantoin toxicity, two cases each of penicillamine, busulphan, BCNU and amiodarone toxicity, and one case each of cyclophosphamide, procainamide, mitomycin and methotrexate toxicity. The HRCT appearances could be grouped into four categories according to their dominant pattern and distribution of disease. These include fibrosis with or without consolidation (n = 12), ground-glass opacities (n = 7), widespread bilateral consolidation (n = 2), and bronchial wall thickening with areas of decreased attenuation (n = 2). The results of this study indicate that HRCT is more sensitive than the radiograph in the detection of drug-induced lung disease. The appearances demonstrated by HRCT reflect the pathological mechanisms of drug-induced lung disease.

Adult↗
PubMed1992

Diseases of the trachea and main-stem bronchi: correlation of CT with pathologic findings.

This article presents the computed tomographic (CT) features of the most common abnormalities of the trachea and main-stem bronchi and correlates CT and pathologic findings. The abnormalities are classified into focal and diffuse. Focal disease tends to produce a decreased airway diameter, whereas diffuse diseases are divided into those that increase the airway diameter and those that decrease it. Conventional CT with 10-mm collimation was performed in 36 patients to assess their condition. Additional dynamic incremental thin-section (1.5-5.0-mm collimation) CT was performed in patients with focal abnormalities. Findings from conventional CT correlated closely with those from pathologic analysis of specimens from patients with diffuse disease, but dynamic thin-section scans are necessary for optimal assessment of focal abnormalities. CT demonstrates the location and extent of disease; helps characterize abnormal tissues; helps evaluate the thickness of the tracheal and bronchial walls; and helps determine the extent of extraluminal disease, including the presence of mediastinal extension and lymphadenopathy.

Bronchi↗
PubMed1992

Primary tuberculosis in childhood: radiographic manifestations.

The aim of the study was to review the radiologic features of primary tuberculosis in childhood and to determine whether differences in patterns of disease occur among age and ethnic groups. Chest radiographs of 191 children with pediatric primary tuberculosis were reviewed by two observers. Lymphadenopathy, present in 92% of cases, was the most common abnormality identified on the initial chest radiograph and typically involved the hilar and paratracheal regions. Parenchymal abnormalities, identified in 70% of cases, occurred more commonly in the right lung (P less than .001). Children 0-3 years of age had a higher prevalence of lymphadenopathy (P less than .01) and a lower prevalence of parenchymal abnormalities (P less than .001) than older children. A lower prevalence of lymphadenopathy was found in whites than in nonwhites (P less than .02). The radiologic abnormalities often progressed in the initial follow-up. Lymphadenopathy, with or without concomitant parenchymal abnormality, is the radiologic hallmark of primary tuberculosis in childhood. However, distinct age-related and racial differences in presenting patterns of disease exist and should be recognized.

Age Factors↗
PubMed1992

High-resolution CT diagnosis of emphysema in symptomatic patients with normal chest radiographs and isolated low diffusing capacity.

To determine the prevalence of "nonobstructive" (impairment of gas transfer) emphysema in a select population of smokers with dyspnea, a retrospective study of patients with emphysema evident at high-resolution computed tomography (HRCT) was undertaken. Four hundred seventy HRCT studies were reviewed. In 47 cases, centrilobular emphysema was the dominant or sole parenchymal abnormality. Concomitant chest radiographs were available in 41 of these cases; 16 of the 41 lacked radiographic findings of emphysema. Among these 16 patients, pulmonary function testing revealed 10 to have normal flow rates (ratio of forced expiratory volume in 1 second to forced vital capacity and forced expiratory volume in 1 second greater than 80% predicted) and impaired gas transfer (single-breath carbon monoxide diffusing capacity [DLCOSB] less than 80% predicted). With the exclusion of one patient with congestive heart failure from the group of 10, the severity of emphysema at HRCT correlated inversely with DLCOSB (r = -.643). These results indicate that HRCT allows detection of emphysema in symptomatic patients when chest radiographs and pulmonary function tests are nondiagnostic.

Female↗
PubMed1992

Thoracic actinomycosis: CT findings in eight patients.

The chest radiographs and computed tomographic (CT) scans obtained in eight patients with pathologically proved cases of thoracic actinomycosis were independently reviewed by two observers. All patients were alcoholic men aged 42-62 years. Air-space consolidation, seen on the radiograph and CT scan in each case, was present in the lower lobes in seven patients (88%) and upper lobes in three (38%). Pleural effusion was present in five (62%). Pleural thickening adjacent to the air-space consolidation was identified on the radiograph in four (50%) and CT scan in all eight. Cavitation or central areas of low attenuation not apparent on the radiograph were seen on the CT scan in five cases (62%). Hilar or mediastinal lymphadenopathy was identified on the radiograph in three cases (38%) and on the CT scan in six (75%). Chest-wall invasion occurred in only one case (12%). Thoracic actinomycosis is characterized on CT scans by air-space consolidation with adjacent pleural thickening. CT is superior to radiography in assessing the thoracic manifestations of actinomycosis.

Actinomycosis↗
PubMed1992

Fibrosing alveolitis: chest radiography and CT as predictors of clinical and functional impairment at follow-up in 26 patients.

Findings on the original and follow-up chest radiographs and computed tomographic (CT) scans were correlated with clinical and functional parameters in 26 patients with fibrosing alveolitis. Assessment of chest radiographs included determination of a standard profusion score and an average profusion score. The CT assessment included pattern, extent, and distribution of disease. The standard profusion score showed no significant correlation with clinical or functional parameters (P greater than .05). However, the average profusion score of the six lung zones correlated with severity of dyspnea and with static lung volumes (P less than .01). Extent of irregular linear opacities on CT scans correlated with severity of dyspnea and impairment in gas transfer (carbon monoxide-diffusing capacity) (P less than .01). The profusion of ground-glass opacities on the radiograph showed no significant correlations (P greater than .05). The profusion and extent of ground-glass opacities on CT scans correlated with severity of dyspnea, impairment in gas transfer, and reduction in static lung volumes (P less than .01). Ground-glass opacities on CT scans preceded and predicted the development of irregular linear opacities on follow-up CT scans and correlated with an increase in the average profusion score of the chest radiograph (P less than .01).

Adrenal Cortex Hormones↗
PubMed1992

Chronic hypersensitivity pneumonitis: high-resolution CT and radiographic features in 16 patients.

To evaluate the manifestations of chronic hypersensitivity pneumonitis at radiography and high-resolution computed tomography (HRCT), findings in 16 patients with this disease were reviewed. To ensure objectivity, 50 patients with other chronic infiltrative lung diseases (fibrosing alveolitis [n = 29], sarcoidosis [n = 16], and miscellaneous conditions [n = 5]) were included. All patients had chronic disease with evidence of fibrosis at HRCT, as indicated by irregular linear areas and architectural distortion. Radiographs and HRCT scans were reviewed separately, in random order, and without knowledge of diagnosis. On radiographs and HRCT scans, the fibrosis in cases of hypersensitivity pneumonitis was situated predominantly in the middle lung zones or showed no zonal predominance. Lung apices and bases were relatively spared in all cases. The distribution of fibrosis in the transverse plane was random in seven cases, subpleural in six, and peri-bronchovascular in three. The distribution of fibrosis can allow distinction of chronic hypersensitivity pneumonitis from other causes of fibrosis in many cases.

Adolescent↗
PubMed1992

Airway narrowing in excised canine lungs measured by high-resolution computed tomography.

The exact site of airway narrowing in asthma and chronic obstructive pulmonary disease is unknown. High-resolution computed tomography (HRCT) is a sensitive noninvasive imaging technique that can be used to measure airway dimensions. After determining the optimal computed tomographic parameters using a phantom, we measured lobe volume and airway dimensions of isolated canine lung lobes at a transpulmonary pressure of 25 cmH2O. These measurements were repeated after deflation and administration of aerosolized saline and carbachol (256 mg/ml). Lobe volume decreased with all treatments. The maximal lobar volume change was 26% at 6 cmH2O after carbachol. Average airway lumen area decreased with all treatments. After carbachol, at transpulmonary pressures of 25, 15, 10, 8, and 6 cmH2O, lumen area decreased by 7.3 +/- 4.1, 62.0 +/- 4.9, 77.5 +/- 3.0, 31.9 +/- 9.0, and 95.2 +/- 1.0% (SE), respectively. When the airways were divided into four categories on the basis of initial lumen diameter (less than 2, 2-4, 4-6, and greater than 6 mm), the greatest decreases in luminal area after carbachol were seen in intermediate-sized airways (2-4 mm, 56 +/- 4%; 4-6 mm, 59 +/- 3%). HRCT can be used to make accurate measurements of airway dimensions and airway narrowing in excised lungs. HRCT may allow measurement of airway wall thickness and determination of the site of airway narrowing in asthma.

Administration, Inhalation↗
PubMed1992

High-resolution computed tomography of experimental hydrostatic pulmonary edema.

To better understand the distribution and clearance mechanisms of extravascular lung water (EVLW) in pulmonary edema, computed tomographic (CT) scans of isolated canine lungs were obtained. In this model, there is no active lymphatic drainage. Fourteen isolated lobes were inflated with oxygen, and edema was induced by infusion of normal saline solution. Two volumes of saline were used, 50 percent and 150 percent of initial wet lobar weight. Six 10-mm- and 1.5-mm-collimation CT scans were obtained at 10-mm intervals from the hilum to the periphery of the lobe before and after each of the two stages of pulmonary edema. The CT scans were reviewed independently by two chest radiologists and were assessed by CT densitometry. Both subjective analysis and CT densitometry showed a predominantly central peribronchial distribution of EVLW in the isolated lungs. Airway wall thickness also increased from the control value (average thickness, 1.0 mm) to 150 percent edema (average thickness, 1.5 mm) (p less than 0.001). We postulate that the peribronchial distribution of fluid is due to a pressure gradient from the alveolar interstitium to the interstitium around the blood vessels and airways at the hilum. This gradient may play a major role in the characteristic perihilar and peribronchial distribution of EVLW seen radiologically in patients with hydrostatic pulmonary edema.

Animals↗
PubMed1992

Value of MR imaging in the evaluation of chronic infiltrative lung diseases: comparison with CT.

The value of MR imaging was compared with that of high-resolution CT in assessing chronic infiltrative lung disease in 25 patients. The cases included nine patients with usual interstitial pneumonia, six with sarcoidosis, four with hypersensitivity pneumonitis, and six with miscellaneous conditions. The diagnosis was proved by biopsy (n = 17) or by means of clinical, laboratory, and radiologic criteria (n = 8). All patients had 1.5-T MR imaging and CT of the chest. Cardiac-gated T1-, proton density-, and T2-weighted spin-echo sequences were obtained. Initially, the MR images were assessed independently; later they were compared directly with the corresponding CT scans. In six patients, MR images and CT scans were obtained before open lung biopsy, and the images and scans were assessed prospectively. CT was superior to MR imaging in the anatomic assessment of the lung parenchyma and in showing fibrosis. However, areas of air-space opacification (ground-glass opacities) were seen as well on MR as on high-resolution CT. In the six patients who had open lung biopsy, areas of air-space opacification seen on MR and on CT corresponded to areas of active alveolitis or air-space infiltrates pathologically. Follow-up in six patients showed equal degrees of change in the air-space opacification over time on MR and CT. We conclude that, although MR imaging is inferior to high-resolution CT in the assessment of chronic infiltrative lung diseases, it may play a role in the assessment and follow-up of patients with air-space opacification.

Adult↗
PubMed1992

High-resolution CT of bronchioloalveolar carcinoma.

Bronchioloalveolar cell carcinoma has a wide spectrum of pathologic and radiologic appearances. Some of the radiologic features are characteristic enough to suggest the underlying pathologic changes. This article illustrates the various manifestations of bronchioloalveolar cell carcinoma on high-resolution CT (1.5-mm collimation reconstructed with a high-spatial-frequency algorithm). Correlations between the CT and pathologic findings are included.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1992

Pulmonary sarcoidosis: changes on follow-up CT examination.

OBJECTIVE: To determine serial changes in the pattern, distribution, and extent of disease over time, and to determine if any specific findings could be used to predict prognosis in patients with pulmonary sarcoidosis, we reviewed the CT scans of 18 patients with pulmonary sarcoidosis. MATERIALS AND METHODS: The study included 18 patients with biopsy-proved sarcoidosis and pulmonary abnormalities who had two serial high-resolution CT examinations (1.5-mm collimation, high-spatial-frequency reconstruction algorithm) 4-49 months apart. Initial and follow-up CT scans were evaluated independently and then directly compared with each other by two observers. Scans were assessed for the presence, extent, and severity of ground-glass, nodular, and irregular linear opacities; interlobular septal thickening; cystic air spaces; and architectural distortion. If a finding was predominant, it was noted. RESULTS: Reversible findings included ground-glass, nodular, and irregular linear opacities and septal thickening. Irreversible findings included cystic air spaces and architectural distortion. Follow-up CT showed overall improvement in 12 of 18 patients, progression in five, and no change in one. A predominant pattern of disease could be determined for each patient. Fourteen patients had predominant nodular opacities; of these, 11 had improved by follow-up. Four had predominant irregular linear opacities; of these, three showed progression of disease on follow-up. The presence of any other specific abnormalities, including ground-glass opacities, was not helpful in predicting improvement or worsening of disease on the follow-up examination. CONCLUSION: In pulmonary sarcoidosis, ground-glass, nodular, and irregular linear opacities and interlobular septal thickening represent potentially reversible disease, while cystic air spaces and architectural distortion are irreversible findings. Follow-up CT usually shows improvement in patients with predominant nodular opacities, while disease tends to progress in patients with predominant irregular opacities.

Adult↗
PubMed1992

MR imaging of the lungs: value of short TE spin-echo pulse sequences.

OBJECTIVE: An experimental short echo delay (TE = 7 msec) T1-weighted spin-echo sequence was compared with a conventional (TE = 20 msec) T1-weighted spin-echo sequence in the assessment of normal and abnormal lung parenchyma. Comparison was also made with high-resolution CT of abnormal lung parenchyma. SUBJECTS AND METHOD: At 1.5 T, an experimental short echo delay T1-weighted multislice spin-echo sequence (TR = RR interval, TE = 7 msec) was compared with an optimal conventional T1-weighted spin-echo sequence (TR = RR interval, TE = 20 msec, spatial presaturation). Ten healthy volunteers were examined with both sequences. The mean signal intensity and signal-to-noise ratios were calculated in lung parenchyma for both sequences. Two radiologists compared the visualization of normal lung parenchymal structures with the two techniques. In 24 patients with diffuse lung disease, results with both MR sequences and with high-resolution CT were compared. RESULTS: The signal intensity was significantly greater (p < .001) with the TE of 7 msec than with the TE of 20 msec, resulting in a 3.5-fold improvement in the signal-to-noise ratio. The 7-msec TE improved visualization of lung parenchymal structures, including peripheral vessels, interlobular septa or veins, and centrilobular arteries. In the patients with diffuse lung disease, pulmonary parenchymal abnormalities were better visualized on the images with TEs of 7 msec than on images with TEs of 20 msec. When compared with high-resolution CT, the sequence with a TE of 7 msec provided comparable assessment of air-space opacification and dense consolidation, but it was inferior to high-resolution CT in the anatomic assessment of lung parenchyma. CONCLUSION: This experimental spin-echo sequence with a TE of 7 msec significantly improves the signal-to-noise ratio, allowing improved visualization of normal and abnormal pulmonary parenchyma when compared with conventional spin-echo images with a TE of 20 msec. Although anatomic detail remains inferior to that seen with high-resolution CT, the improved image quality with a TE of 7 msec suggests that assessment and follow-up of parenchymal lung disease might be possible with MR, thereby avoiding ionizing radiation.

Adult↗
PubMed1992

The diaphragm.

Intrinsic disorders of the diaphragm are uncommon. However, the diaphragm is a useful radiographic landmark for detecting adjacent pulmonary, pleural and abdominal abnormalities, which may lead to the elevation of one or both hemidiaphragms or to focal irregularities in the diaphragmatic contour. In this review the authors summarize the most common diaphragmatic abnormalities and suggest the optimal approach for each to allow a specific diagnosis.

Diaphragm↗
PubMed1992

Wegener's granulomatosis: findings from computed tomography of the chest in 10 patients.

Radiographs and computed tomography (CT) scans of the chest were reviewed for 10 patients with pathologically proven Wegener's granulomatosis. The CT scans revealed multiple pulmonary nodules in seven patients and a single nodule in one. The nodules ranged in diameter from 2 mm to 7 cm, and most had irregular margins. All of the nodules larger than 2 cm in diameter showed evidence of cavitation in the CT scans. Additional CT findings included associated areas of consolidation (in two patients), pleural thickening (in two) and pleural effusion (in two). Chest radiographs were available for eight patients, and the CT scans contributed information additional to that available from the radiographs for seven of these. In one patient lung nodules were visible in the CT scans but could not be distinguished from surrounding areas of consolidation in the chest radiographs. CT revealed additional nodules in five of the six patients in whom multiple nodules were seen in chest radiographs and in one of these also revealed cavitation tht was not visible in plain radiographs. CT excluded the possibility of a nodule that was suspected from the chest radiographs in a patient who had been treated previously for Wegener's granulomatosis. The authors conclude that Wegener's granulomatosis is characterized in CT scans by multiple nodules with irregular margins and by cavitation in nodules larger than 2 cm in diameter. CT may also demonstrate nodules and cavitation not apparent in radiographs.

Adolescent↗
PubMed1991

Solitary pulmonary nodule: high-resolution CT and radiologic-pathologic correlation.

Edge and internal characteristics of pulmonary nodules evaluated with high-resolution computed tomography (HRCT) were correlated with the pathologic specimens in 93 patients. Speculation correlated pathologically with irregular fibrosis, localized lymphatic spread of tumor, or an infiltrative tumor growth pattern and was observed in six of 11 benign nodules (55%) and 74 of 85 malignant nodules (87%). Pleural tags were observed in three benign nodules (27%) and 49 malignant lesions (58%); pathologically, these represented fibrotic bands usually associated with juxta-cicatricial pleural retraction. Bubblelike areas of low attenuation within the nodule were observed in 21 malignant lesions (25%) and only one benign nodule (9%). They were observed most commonly in bronchioloalveolar carcinomas (seven of 14) and were due either to patent small bronchi or small, cystic spaces within neoplastic glands. Malignant nodules as a group were larger than benign lesions (P = .02) and more commonly demonstrated a spiculated contour (P less than .05), lobulation (P less than .001), and inhomogeneous attenuation (P less than .05).

Adult↗
PubMed1991

Low-dose high-resolution CT of lung parenchyma.

To evaluate the efficacy of low-dose high-resolution computed tomography (HRCT) in the assessment of lung parenchyma, three observers reviewed the scans of 31 patients. The 1.5-mm-collimation, 2-second, 120-kVp scans were obtained at 20 and 200 mA at selected identical levels in the chest. The observers evaluated the visualization of normal pulmonary anatomy, various parenchymal abnormalities and their distribution, and artifacts. The low-dose and conventional scans were equivalent in the evaluation of vessels, lobar and segmental bronchi, and anatomy of secondary pulmonary lobules, and in characterizing the extent and distribution of reticulation, honeycomb cysts, and thickened interlobular septa. The low-dose technique failed to demonstrate ground-glass opacity in two of 10 cases (20%) and emphysema in one of nine cases (11%), in which they were evident but subtle on the high-dose scans. These differences were not statistically significant. Linear streak artifact was more prominent on images acquired with the low-dose technique, but the two techniques were judged equally diagnostic in 97% of cases. The authors conclude that HRCT images acquired at 20 mA yield anatomic information equivalent to that obtained with 200-mA scans in the majority of patients, without significant loss of spatial resolution or image degradation due to linear streak artifact.

Adult↗