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N L Müller

Publications and source records attributed to N L Müller.

At least 127 records · Page 7Linked to original sources
PubMed1995

CT mosaic pattern of lung attenuation: etiologies and terminology.

Areas of variable lung attenuation forming a "mosaic pattern" are occasionally seen on computed tomography (CT) or high-resolution CT (HRCT) images of the lungs. This CT mosaic pattern of lung attenuation is a nonspecific finding that can reflect the presence of vascular disease, airway abnormalities, or ground-glass interstitial or air-space infiltrates. However, it is often possible to distinguish among these categories. In small airways disease and pulmonary vascular disease, the pulmonary vessels within the lucent regions of lung are small relative to the vessels in the more opaque lung. In infiltrative diseases, the vessels are more uniform in size throughout the different regions of lung attenuation. The distinction of small airways disease from primary vascular disease requires the use of paired inspiratory/expiratory CT scans. The terms "mosaic perfusion" or "mosaic oligemia" have also been used to describe this heterogeneous pattern of lung attenuation. We believe that the term "mosaic pattern of lung attenuation" is preferable when describing areas of variable lung attenuation because the term "mosaic perfusion" implies pulmonary vascular pathology.

Adolescent↗
PubMed1994

MR imaging of chest wall lesions.

To assess the magnetic resonance (MR) imaging findings of chest wall lesions, images from 45 patients were reviewed by two experienced chest radiologists. The study included 14 benign and 31 malignant lesions. Images were obtained on 1.5-T imagers with use of conventional T1-, proton-density, and T2-weighted sequences in transverse, coronal, and sagittal imaging planes. Where appropriate, motion artifact was minimized with respiratory compensation, spatial presaturation, flow compensation, and cardiac gating. Twelve of 14 benign lesions showed well-defined, smooth margins compared with 10 of 31 malignant lesions (P < .05). The remaining 21 malignant lesions had irregular or ill-defined margins and evidence of muscle, bone, or vascular invasion. A capsule or pedicle was seen only in benign lesions. Characteristic MR signal intensity was seen in all four lipomas and in the only arteriovenous malformation. The remaining benign and malignant lesions showed nonspecific signal intensity characteristics. MR imaging allows the detection of muscle, bone, or vascular invasion by chest wall tumors. However, as in other musculoskeletal regions, MR imaging does not allow confident distinction of benign from malignant chest wall lesions.

Adolescent↗
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

Acute lung disease in the immunocompromised host: CT and pathologic examination findings.

PURPOSE: To compare findings at computed tomography (CT) and pathologic examination in immuno-compromised patients with acute lung disease. MATERIALS AND METHODS: Findings in 33 chest CT scans were compared with findings in pathologic specimens obtained at open lung biopsy (n = 29) or autopsy (n = 4) in 32 patients, aged 17-64 years. RESULTS: Nodules were the main abnormality at CT in 14 cases. Pathologically, the 14 nodules were due to infection (n = 10), bronchiolitis obliterans organizing pneumonia (BOOP) (n = 3), or lymphoma (n = 1). Areas of ground-glass attenuation were the main finding in 15 patients. These areas were a result of BOOP (n = 4), cytotoxic drug reaction (n = 4), infection (n = 4), lymphoma (n = 2), or nondiagnostic biopsy (n = 1). Consolidation was the main finding in four cases, being seen with BOOP (n = 2), infarction due to fungal infection (n = 1), and diffuse pulmonary hemorrhage (n = 1). CONCLUSION: The pattern at CT accurately reflected the gross morphologic features seen in the pathologic specimens. Nodules were usually inflammatory lesions, often infections, and open lung biopsy usually revealed their specific origin.

Acute Disease↗
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↗
PubMed1994

Chronic infiltrative lung disease: comparison of diagnostic accuracies of radiography and low- and conventional-dose thin-section CT.

PURPOSE: To compare the accuracy of low-dose thin-section computed tomography (CT), chest radiography, and conventional-dose thin-section CT in diagnosis of chronic infiltrative lung disease (CILD). MATERIALS AND METHODS: Chest radiographs and low-dose (80-mAs) and conventional-dose (340-mAs) thin-section (1.5-mm) CT scans from 50 patients with CILD and 10 healthy control subjects were randomized and analyzed retrospectively. For CT, three images were obtained: at the aortic arch, at the tracheal carina, and 1 cm above the right hemidiaphragm. Two independent observers listed three likely diagnoses and recorded the degree of confidence in their first choice. RESULTS: A correct first-choice diagnosis was made more often with either CT technique than with radiography (P < .02). A high confidence level in the diagnosis was reached in 42% of radiographic, 61% of low-dose CT, and 63% of conventional-dose CT interpretations, which were correct in 92%, 90%, and 96% of the studies, respectively. CONCLUSION: The superior diagnostic accuracy of low-dose thin-section CT was achieved without an increase in effective radiation dose.

Adult↗
PubMed1994

Invasive aspergillosis of the airways: radiographic, CT, and pathologic findings.

PURPOSE: To assess the radiographic, computed tomographic (CT), and pathologic findings in invasive aspergillosis of the airways. MATERIALS AND METHODS: The study included nine consecutive patients (aged 17-65 years [median, 49 years]) with pathologically proved invasive aspergillosis of the airways. All nine underwent chest radiography and seven underwent CT within 3 days of diagnosis. RESULTS: The radiographic findings include normal parenchyma (n = 1), unilateral consolidation (n = 1), bilateral consolidation (n = 5), and ill-defined nodules (n = 2). The main findings at CT included lobar consolidation (n = 1), bilateral predominantly peribronchial consolidation (n = 3), ground-glass attenuation (n = 1), and centrilobular nodules less than 5 mm in diameter (n = 2). At pathologic examination, the peribronchial infiltrates represented bronchopneumonia and the nodules represented Aspergillus bronchiolitis with a variable degree of peribronchiolar organizing pneumonia and hemorrhage. CONCLUSION: Radiographic findings of invasive aspergillosis of the airways consist of consolidation or ill-defined nodules. At CT, the consolidation can be seen to be peribronchial and the nodules centrilobular.

Adolescent↗
PubMed1994

Bronchogenic carcinoma: utility of CT in the evaluation of patients with suspected lesions.

PURPOSE: To assess the utility of computed tomography (CT) in the evaluation of suspected bronchogenic carcinoma. MATERIALS AND METHODS: CT scans were reviewed of 362 patients who had undergone CT for suspected bronchogenic carcinoma. RESULTS: CT findings of 275 patients were consistent with bronchogenic carcinoma. Sixty-five tumors were deemed unresectable on the basis of CT findings, 21 were deemed unresectable on the basis of CT findings and poor surgical risk, 26 proved to be benign, six were metastatic disease from an extrathoracic primary tumor, and 157 were potentially resectable bronchogenic carcinoma. Surgical mediastinal nodal sampling enabled documentation of metastases in 60 of 159 patients. According to nodal station, the sensitivity of CT for metastases was 67% for nodes measured in the long axis and 58% for nodes measured in the short axis; specificity was 56% and 86%, respectively. CONCLUSION: CT can be used to confirm or exclude the presence of bronchogenic carcinoma and to obviate thoracotomy. The specificity of CT is limited, and a histologic diagnosis or follow-up evaluation is necessary. CT has limited value in staging mediastinal lymph nodes.

Carcinoma, Bronchogenic↗
PubMed1994

Idiopathic giant bullous emphysema (vanishing lung syndrome): imaging findings in nine patients.

OBJECTIVE: We reviewed the imaging findings in nine patients with idiopathic giant bullous emphysema. This progressive condition is characterized by large bullae, usually seen in association with several forms of emphysema, and usually occurs in young men, most of whom are smokers. MATERIALS AND METHODS: Nine patients with chest radiographic evidence of a bulla or bullae occupying at least one third of a hemithorax, who had also been examined with high-resolution CT, were included in this retrospective study. We examined the size, distribution, and locations of bullae. On high-resolution CT scans, bullae were categorized as predominantly subpleural or intraparenchymal. RESULTS: In eight of the nine cases, the chest radiographs showed variable asymmetry in the distribution of bullae. Bullous disease involved predominantly the upper lobes. High-resolution CT showed bullae from 1 to 20 cm in diameter, but most were 2-8 cm in diameter. Paraseptal emphysema and subpleural bullae were the predominant findings in all nine patients. Seven patients had separate centrilobular emphysema of various degrees and intraparenchymal bullae. None of the intraparenchymal bullae were larger than 2-3 cm. Additionally, two non-small-cell lung cancers were seen in our series. CONCLUSION: The dominant and consistent feature seen on high-resolution CT scans in both smokers and nonsmokers is extensive paraseptal emphysema merging into giant bullae. Associated centrilobular emphysema, seen in cigarette smokers, is the important variable finding for determining the extent of underlying parenchymal disease, which may help in the preoperative assessment of giant bullous lung disease.

Adult↗
PubMed1994

Cryptogenic organizing pneumonia: CT findings in 43 patients.

OBJECTIVE: Description of the CT findings of cryptogenic organizing pneumonia has been limited to a small number of cases. This study was performed to characterize the CT findings of this disease in a larger number of cases and to compare the findings in immunocompetent and immunocompromised patients. MATERIALS AND METHODS: The CT scans of 43 (32 immunocompetent and 11 immunocompromised) patients who had biopsy-proved cryptogenic organizing pneumonia were reviewed. The scans were obtained by using contiguous 8- or 10-mm collimation and selected thin (1.5 or 2.0 mm) section (n = 23), thin-section collimation at 10-mm intervals (n = 12), or 8- or 10-mm collimation only (n = 8). The scans were analyzed by three observers, and final decisions were reached by consensus. RESULTS: The most common pattern seen was consolidation, which was present alone or as part of a mixed pattern in 34 cases (79%). The consolidation had a predominantly subpleural and/or peribronchovascular distribution in 27 cases (63%). Ground-glass attenuation and nodules were seen in 26 patients (60%) and 13 patients (30%), respectively, and were usually random in distribution. Consolidation was present in 91% (29/32) of immunocompetent and 45% (5/11) of immunocompromised patients (p < .01). Ground-glass attenuation was present in 56% (18/32) of immunocompetent and 73% (8/11) of immunocompromised patients (p > .25). Nodules were present in seven (22%) of 32 immunocompetent patients and six (55%) of 11 immunocompromised patients (p < .025). CONCLUSION: We conclude that in immunocompetent patients the CT findings in cryptogenic organizing pneumonia most commonly consist of bilateral areas of consolidation involving mainly the subpleural and/or peribronchovascular regions. In the immunocompromised patient, the CT findings are variable.

Adult↗
PubMed1994

Diagnosis of thoracic complications in AIDS: accuracy of CT.

OBJECTIVE: The purpose of this study was to assess the accuracy of CT interpretation in the diagnosis of thoracic complications of AIDS. If CT is accurate, more invasive diagnostic procedures can be avoided. MATERIALS AND METHODS: We reviewed the CT scans of 102 patients who had AIDS with proved thoracic complications and 20 HIV-positive patients without active intrathoracic disease. The scans were independently assessed by two observers from a different institution who did not know the clinical or pathologic data. The observers listed the three most likely diagnoses in order of probability and recorded the degree of confidence in their first-choice diagnosis. Imaging diagnoses were compared with final diagnoses based on results of sputum cultures, bronchoscopy, fine-needle aspiration, mediastinoscopy, open lung biopsy, autopsy, gallium scans, other clinical data, and extensive follow-up. RESULTS: Nineteen of the 20 cases in which no active disease was present were correctly identified by one observer, and 18 were correctly identified by the other. All 102 cases of active disease were correctly identified as abnormal by one observer, and 101 cases were identified as abnormal by the second observer. The correct first-choice diagnosis, regardless of the degree of confidence, was made in 66% of the cases. A confident diagnosis was made in 48% of all cases, and the observers were correct in 92% of those cases. There was good agreement between the two observers in the confident diagnosis based on CT (kappa statistic = 0.71). The interpretations of CT scans were most often accurate in the confident diagnosis of pneumocystis pneumonia (94%) and Kaposi's sarcoma (90%) and in the exclusion of active thoracic disease (93%). CONCLUSION: Certain findings on chest CT scans allow confident diagnoses of specific complications in patients with AIDS. CT-based diagnosis may preclude more invasive diagnostic procedures in selected cases.

AIDS-Related Opportunistic Infections↗
PubMed1994

Metastatic pulmonary calcification in patients with hypercalcemia: findings on chest radiographs and CT scans.

OBJECTIVE: The objective of this study was to characterize the findings on chest radiographs and CT scans in patients with metastatic pulmonary calcification due to hypercalcemia. MATERIALS AND METHODS: The chest radiographs and CT scans of seven patients with biopsy-proved metastatic pulmonary calcification were reviewed by two observers. Metastatic calcification was due to chronic renal failure (n = 4), T-cell leukemia (n = 1), multiple endocrine neoplasia type I syndrome (n = 1), and idiopathic hypercalcemia (n = 1). RESULTS: Numerous nodular opacities measuring 3-10 mm in diameter were seen on the chest radiographs in five cases, and patchy areas of parenchymal opacification were seen in two cases. Calcification of the nodules was evident in two cases. On CT scans, pulmonary nodules were present in all seven cases. These nodules were predominant in the upper lung zone in three cases, were diffuse in three cases, and were predominant in the lower lung zone in one case. Calcification of the nodules was evident on the CT scans in four of the seven cases, and calcification of vessels in the chest wall was evident in six of seven cases. Other findings on CT scans included diffuse areas of ground-glass attenuation (n = 3) and patchy consolidation (n = 2). CONCLUSION: Numerous small nodules are the most common finding on the chest radiographs of patients with metastatic pulmonary calcification. The calcific nature of the nodules is seldom obvious, however. Pulmonary nodules are also the most common finding on CT scans, where the calcific nature of the nodules is more readily apparent. Additionally, calcification is often seen in the vessels of the chest wall on CT scans. The combination of calcified nodules and calcified vessels in the chest wall on CT scans may be characteristic.

Adult↗
PubMed1994

Combined lobar atelectasis of the right lung: imaging findings.

Combined lobar atelectasis refers to the condition in which the volumes of two lobes of the lung are decreased simultaneously. Because the right lung has three lobes, three combinations of combined atelectasis are possible. The most frequent combination is that of middle and lower lobar atelectasis caused by obstruction of the bronchus intermedius [1,2]. Combined atelectasis of the upper and middle lobes is uncommon, although it occurs more frequently than anticipated [1]. The least common combination is that of right upper and lower lobe atelectasis. Awareness of the radiographic and CT findings of combined lobar atelectasis of the right lung is important in making the correct diagnosis. In this pictorial essay, we illustrate the spectrum of radiographic and CT features of this condition.

Adult↗
PubMed1994

Emphysema: definition, imaging, and quantification.

This review will discuss imaging of the chest in patients with pulmonary emphysema. Imaging findings must be related to the structure of the lung because emphysema is defined in anatomic terms. Accordingly, we first review the anatomic definitions of emphysema and its consequences and then review the imaging findings, with emphasis on CT, in patients with this disease. The more severe the morphologic emphysema, the more likely a radiographic diagnosis will be made, no matter what criteria are used. The criterion of arterial deficiency is specific but insensitive. The criteria used to assess overinflation are sensitive but not specific. CT can be used for both qualitative and quantitative assessment of emphysema. The presence and extent of emphysema can be determined by visual assessment of areas of abnormally low attenuation or by objective quantification based on the attenuation values. Statistically significant correlations between emphysema and CT findings have been shown in numerous studies, but mild morphologic emphysema may be missed by CT, and occasionally CT scans give false-positive findings. In patients with moderate to severe emphysema, the severity of emphysema is underestimated on the basis of CT findings by a factor of approximately three when compared directly with results of pathologic examination of lung specimens. In spite of these limitations, CT is the best way of recognizing emphysema in living patients and probably has a significant role in recognizing localized emphysema that is amenable to surgical treatment.

Female↗
PubMed1994

High-resolution computed tomography in acute diffuse lung disease in the immunocompromised patient.

A number of studies have shown that high-resolution CT (HRCT) scanning may be helpful in the assessment of acute diffuse lung disease in immunocompromised patients. HRCT may demonstrate abnormalities when the radiograph is normal and may allow for a more confident diagnosis in patients with nonspecific radiographic findings. Because HRCT is superior in demonstrating the distribution and extent of parenchymal abnormalities, it is also helpful as a guide to the optimal type and site of lung biopsy. This article reviews the HRCT manifestations of the most common causes of acute diffuse lung disease in the immunocompromised host, including infection, drug-induced lung disease, pulmonary edema, and neoplasms.

AIDS-Related Opportunistic Infections↗