Congenital bronchial atresia: radiologic findings in nine patients

PURPOSE: The purpose of this article is to describe the radiologic findings to diagnose congenital bronchial atresia. METHODS: Chest radiographs, CT scans, and MRI of nine patients with congenital bronchial atresia were reviewed. RESULTS: Six patients (67%) had hilar mass-like shadows and hyperlucency of the peripheral lung field on chest radiographs. On chest CT scans, all patients demonstrated mucocele, occlusion of bronchus central to mucocele, and emphysematous change of the peripheral lung field. On chest MRI, performed in seven patients, all mucoceles demonstrated very high signal intensity on T2-weighted image, indicating that mucoceles were filled with fluid. CONCLUSION: Diagnosis of congenital bronchial atresia can be confirmed based on the findings of chest CT: mucocele, occlusion of bronchus central to mucocele, and emphysematous change of the peripheral lung field.     

Exogenous lipoid pneumonia: high-resolution CT findings

The aim of this study was to assess high-resolution computed tomography (HRCT) findings of exogenous lipoid pneumonia. High-resolution computed tomography was obtained in 25 patients with proven exogenous lipoid pneumonia resulting from aspiration of squalene (derived from shark liver oil). Diagnosis was based on biopsy (n = 9), bronchoalveolar lavage (n = 8), or sputum cytology and clinical findings (n = 8). The clinical history of taking squalene was confirmed in all patients. The CT findings were classified into three patterns: diffuse ground-glass opacity, consolidation, and interstitial abnormalities. Distribution of the abnormalities, duration of taking squalene, predisposing factors for aspiration, and route of administration were analyzed. Ten patients showed diffuse ground-glass opacity pattern. Seven of 10 patients had predisposing conditions such as unconsciousness, pharyngeal dysmotility, or motor disturbances, and 6 patients had a recent history of taking large amount of squalene through nasal route. Seven patients who had consolidation pattern had a history of taking squalene for several months and did not have any predisposing factor. All of the 5 patients who had a pattern of interstitial abnormalities had a history of taking squalene longer than 1 year and showed segmental distribution of interstitial thickening with interposing ground-glass opacities. Three patients simultaneously had two different patterns at different lobes of the lung. The HRCT findings of lipoid pneumonia are ground-glass opacities, consolidation, and interstitial abnormalities. These HRCT findings with appropriate inquiries could be useful for diagnosis of exogeneous lipoid pneumonia. Received: 12 September 1997; Revision received: 13 February 1998; Accepted: 7 April 1998     

Radiological findings in nine AIDS patients with Rhodococcus equi pneumonia

Rhodococcus equi (R. equi) infections have been incidentally reported as a cause of pulmonary infection in severely immunocompromised hosts, including AIDS patients. Our purpose is to describe the radiological findings in nine AIDS patients with R. equi pneumonia assessed by bronchoalveolar lavage (BAL), biopsies, cultures of sputum, and hemocultures. All patients were examined by chest radiographs and contrast-medium-enhanced chest CT. Dense pulmonary consolidations with or without cavitations accounted for the most striking radiological patterns. Chest CT also revealed six mediastinal involvements, strongly mimicking a lymphoma. Two of them had multiple bilateral pulmonary nodular opacities. Pleural effusion was not identified. Although intensive therapies were administered, seven among nine patients died within few months. In an AIDS patient living in a rural area or exposed to horses and presenting these radiological patterns, the possibility of R. equi pneumonia should be considered in the differential diagnosis along with other infectious diseases or lymphomas.Correspondence to: P. Schnyder     

Semiinvasive pulmonary aspergillosis in chronic obstructive pulmonary disease: radiologic and pathologic findings in nine patients

OBJECTIVE: The purpose of this study is to assess the radiographic, thin-section CT, and histologic findings of semiinvasive aspergillosis in patients with chronic obstructive pulmonary disease (COPD). MATERIALS AND METHODS: The study included nine patients with COPD seen at the Hospital de Sant Pau during a 3-year period who had histopathologically proven aspergillosis with tissue invasion. Chest radiography and thin-section (2-mm collimation) CT of the chest were available in all cases. RESULTS: Nine patients had semiinvasive aspergillosis proven at autopsy (n = 7) or by thoracoscopically guided lung biopsy (n = 2). The radiologic findings consisted of parenchymal consolidation (n = 6) and nodules larger than 1 cm in diameter (n = 3). Parenchymal consolidation involved the upper lobes in five patients and was bilateral in four. Cavitation was present in two of the patients with consolidation and in two of the patients with nodular opacities. Adjacent pleural thickening was revealed by CT in four patients. Histologically, the areas of consolidation represented active inflammation and intraalveolar hemorrhage containing Aspergillus organisms. In the three patients with multiple cavitated nodules, a variable degree of central necrosis was observed. The inflammatory infiltrate extended into the surrounding lung parenchyma, and adjacent areas of hemorrhage were also seen. Aspergillus colonies were identified within the lung tissue. CONCLUSION: Upper lobe consolidation or multiple nodules in patients with COPD should raise the possibility of semiinvasive aspergillosis.     

Pleuropulmonary paragonimiasis: radiologic findings in 71 patients.

Pleuropulmonary paragonimiasis is a disease caused by lung flukes characterized by migration of a juvenile worm in the early stage and by formation of cysts around the worm later on. The purpose of this study was to describe the radiologic manifestations of pleuropulmonary paragonimiasis, with special emphasis on the worm cyst and worm migration track. We retrospectively studied 71 patients who had evidence of pleuropulmonary paragonimiasis on chest radiographs (n = 71) and CT scans (n = 17). The diagnosis was based on the detection of eggs or on positive antibody tests. On chest radiographs, 59 patients (83%) had pulmonary lesions and 43 patients (61%) had pleural lesions. Pulmonary findings included patchy air-space consolidation (n = 37) with or without cystic changes; ring shadows (n = 16); and peripheral linear opacities (n = 29), which were more prominent in patients with pleural effusion. Twelve patients (17%) had bilateral pleural effusions or pneumothoraces. On CT scans, round low-attenuation cystic lesions (5-15 mm), filled either with fluid (n = 5) or gas (n = 5), were characteristically seen within the consolidation. Peripheral linear opacities seen on radiographs were suggestive of worm migration tracks on CT scans. CT may reveal an intracystic worm. Although the findings vary depending on the stage of the disease, findings on chest radiographs are usually typical of paragonimiasis. CT provides more specific information about the worm cyst and the worm migration track.     

Exogenous lipoid pneumonia: HRCT, MR, and pathologic findings

The objective of this study was to describe high-resolution CT (HRCT) and MR findings of exogenous lipoid pneumonia and to correlate them with pathologic findings. A retrospective review of the medical records of our institution revealed seven patients with a diagnosis of lipoid pneumonia based on clinical data, chest films, bronchoalveolar lavage, and follow-up. Both HRCT and MR imaging were reviewed by two readers. Pathologic examination of the resected specimen or surgical biopsies were also reviewed in the four available cases. The HRCT findings were pulmonary consolidations (n = 6) with fatty (n = 3) or unspecific but low attenuation values (n = 3), areas of ground-glass opacities (n = 5), septal lines, and centrilobular interstitial thickening (n = 5). In five of the seven cases, a crazy-paving pattern of various spread was also present, either isolated (n = 1) or surrounding a pulmonary consolidation. In two cases traction bronchiectasis and cystic changes consistent with fibrosis were seen. At MR imaging (n = 2) a pulmonary consolidation of high signal intensity on T1-weighted image consistent with lipid content was present in one case. Pathologic examination (n = 4) showed the coexistence of lobules with lesions of various ages, sometimes in contiguous lobules, within the same patient. Recent lesions were those with alveolar fill-in by spumous macrophages and almost normal alveolar walls and septae. In more advanced lesions, lobules were filled in with larger vacuoles often surrounded by inflammatory infiltrates of alveolar walls, bronchiolar walls, and septa. The oldest lesions were characterized by fibrosis and parenchymal distortion around large lipid-containing vacuoles. The HRCT findings reflect pathologic findings in exogenous lipoid pneumonia. Although non-specific, consolidation areas of low attenuation values and crazy-paving pattern are frequently associated in exogenous lipoid pneumonia and are indicative of the diagnosis. Received: 24 July 1998; Revision received: 30 December 1998; Accepted: 1 February 1999     

Myelolipoma: radiologic findings in seven patients

Myelolipomas are rare, non-functioning, benign tumors which occur both in the adrenal gland and in various extra-adrenal locations, particularly presacrally. We report the computed tomographic (CT) and ultrasonographic (US) findings in seven patients with pathologically proven myelolipomas. Magnetic resonance (MR) imaging was also obtained in one. Our series includes one patient with bilateral myelolipomas, one with a presacral myelolipoma, and one with a calcified myelolipoma. Radiographic findings can suggest the diagnosis. A characteristic mass is lucent on plain films, is echogenic on US, shows fat attenuation on CT, is avascular at angiography, and has a signal intensity similar to that of fat on T1-weighted MR images. However, the absence of fat can render imaging findings nonspecific. Percutaneous needle biopsy is a simple, safe, effective way to establish the diagnosis when imaging features are not typical.     

Shark liver oil-induced lipoid pneumonia in pigs: correlation of thin-section CT and histopathologic findings.

PURPOSE: To evaluate sequential changes in thin-section computed tomographic (CT) findings after inducement of lipoid pneumonia and provide the histopathologic bases of these findings. MATERIALS AND METHODS: Shark liver oil was administered to 12 sites in seven pigs. Thin-section CT scans were obtained within 1 hour and at 1 week, 2 weeks, 4 weeks, 8 weeks, 12 weeks, and 16 weeks after oil administration. Scans were assessed for opacity, distribution, location at the lobular level, extent, and volume of the lesions. The CT number in consolidation areas also was measured. Findings at CT were correlated with those in the histopathologic specimens. RESULTS: Diffuse ground-glass opacity was noted on all immediately obtained scans. The opacity of the lesions was highest at 1 week; then it decreased gradually to an area of ground-glass opacity. The extent and volume of the lesions decreased at follow-up CT. Histopathologically, the lesions showed a lobular distribution sharply demarcated from the normal lungs. The lobules of decreased volume showed residual thickening of the alveolar walls with bronchiolectasis and mild collagen deposition of the interlobular septa. Pathologic examination of the low-attenuating consolidation area at CT revealed evidence of partial aeration. CONCLUSION: Thin-section CT findings of lipoid pneumonia include ground-glass opacity and airspace consolidation, followed by complete or incomplete resolution with volume loss and septal thickening. Low-attenuating consolidation at CT does not always indicate the presence of fat.     

Cloacal exstrophy: radiologic findings in 13 patients

Cloacal exstrophy is a complex, multisystem malformation that has not received much attention in the radiologic literature. The clinical histories and imaging studies of 13 cases of cloacal exstrophy proved surgically or at autopsy were reviewed. Radiologic observations were based on skeletal plain films (13), contrast-enhanced examinations of the genitourinary system (12), abdominopelvic sonograms (nine), gastrointestinal studies (seven), CT scans of the pelvis and CNS (seven), MR images of the pelvis and CNS (six), renal nuclear medicine scans (three), myelography (three), and three-dimensional scans of the pelvis (two). Genitourinary and gastrointestinal abnormalities identified in our 13 patients included bladder malformations (13), hindgut anomalies (13), undescended testes (five), malrotation (five), duplicated müllerian structures (four), and renal ectopia (four). Skeletal abnormalities included symphysis pubis diastasis (13), posterior element dysraphism (12), vertebral segmentation anomalies (12), clubfeet (six), and hip dislocations (five). CNS anomalies included meningocele (nine) and Chiari malformation (one). Immediate surgical closure of the defect with maximal bowel preservation and diverting colostomy offers optimal chances for survival. Appropriate preoperative gastrointestinal and genitourinary evaluation is essential.     

Pulmonary blastoma: radiologic findings in five patients

PURPOSE: To determine the radiologic findings of pulmonary blastoma on chest radiograph and CT. MATERIALS AND METHODS: Chest radiographs and CT scans of five patients with pathologically proven pulmonary blastoma were retrospectively evaluated and radiologic findings were correlated with histopathologic findings. RESULTS: On chest radiograph, the pulmonary blastoma manifested as a solitary parenchymal mass (n = 2), a solitary parenchymal nodule (n = 1), hilar bulging with fingerlike parenchymal opacities (n = 1), or opacification of hemithorax (n = 1). On CT, the pulmonary blastoma manifested as a solitary parenchymal mass (n = 2), a solitary parenchymal nodule (n = 1), an endobronchial mass with postobstructive pneumonitis (n = 1), or a parenchymal mass with multiple subpleural masses and pleural effusion (n = 1). CONCLUSION: Pulmonary blastomas most commonly manifested as a solitary parenchymal mass on chest radiograph and CT. These radiologic features are nonspecific and many primary or metastatic tumors of the lung could be included in differential diagnosis.     

Enteroenteric intussusception: CT findings in nine patients

The CT scans in nine proven cases of enteroenteric intussusception were analyzed. Three different CT patterns were observed: a target lesion (n = 5), a reniform mass (n = 2), and a sausage-shaped mass with alternating layers of low and high attenuation (n = 2). Small-bowel series were available within 2-4 days of CT in eight patients and were positive in five. Surgical proof of intussusception was available in seven of the nine patients. Resected small-bowel specimens from patients with the reniform configuration revealed focal ischemic changes. Other objective parameters of ischemia such as acidosis and hyperamylasemia were also present in the two patients with reniform masses. Such changes were not evident in the other patients. This suggests that intussusceptions with reniform configurations warrant more urgent surgical attention. The varying patterns of intussusception on CT should be recognized so that appropriate management can be initiated.     

AIDS-related cholangitis: radiographic findings in nine patients

Acalculous inflammation of the biliary tract is a recently reported complication of the acquired immunodeficiency syndrome (AIDS). In a 33-month period, nine men with AIDS were evaluated because of right upper quadrant and/or epigastric pain, jaundice, or abnormal liver function test results. Each patient underwent ultrasonography and endoscopic retrograde cholangiopancreatography; seven also underwent computed tomography. In eight of nine patients the imaging studies disclosed intrahepatic and extrahepatic bile duct changes identical to those seen in sclerosing cholangitis (strictures, focal dilatation, thickened duct walls). Isolated papillary stenosis and ductal dilatation were present in one patient, while eight patients had some stricturing of the distal common duct. The combination of papillary stenosis and intrahepatic ductal strictures appears unique to AIDS-related cholangitis. Endoscopic papillotomy provided variable relief to symptoms and biochemical abnormalities. Cholangitis caused by cytomegalovirus and/or Cryptosporidium infection is the proposed pathophysiologic mechanism.     

Bronchiolitis obliterans in heart-lung transplantation patients: radiologic findings in 11 patients

Patients who survive the postoperative period after combined heart-lung transplantation are at risk for developing progressive airway damage consisting of central bronchiectasis and bronchiolitis obliterans. The cause of these abnormalities is uncertain, but they are thought to represent a form of chronic rejection. The chest radiographs and medical records of 11 transplantation patients with proved bronchiolitis obliterans were reviewed retrospectively. A pathologic diagnosis was made by open-lung biopsy (five patients), transbronchial biopsy (three patients), and autopsy (two patients). Clinical criteria alone were used for diagnosis in one patient. In all patients, the chest radiographs showed parenchymal abnormalities consisting of linear-nodular, nodular, confluent nodular, or diffuse alveolar opacities. Radiographic evidence of central bronchiectasis was present in nine of the 11 patients. This feature was not present on chest radiographs of five randomly selected asymptomatic transplant patients. We conclude that the parenchymal lung changes in bronchiolitis obliterans in transplant patients are nonspecific and are radiographically indistinguishable from other infectious and noninfectious complications. The presence of central bronchiectasis (nine of the 11 patients) may be a distinctive radiographic finding in this group of patients.     

Acute interstitial pneumonia: thin-section CT findings in 36 patients.

PURPOSE: To characterize the computed tomographic (CT) findings of acute interstitial pneumonia and to correlate the pattern and the extent of abnormalities with the time between symptom onset and CT. MATERIALS AND METHODS: The study included 36 patients (20 men, 16 women; age range, 22-83 years; mean age, 61 years) with histopathologically proved acute interstitial pneumonia who were identified retrospectively. The time between symptom onset and CT was 2-90 days (mean, 22 days; median, 17 days). The presence, extent, and distribution of various CT findings were evaluated. Disease duration and extent of each finding were compared by using the Spearman rank correlation coefficient. RESULTS: Areas with ground-glass attenuation, traction bronchiectasis, and architectural distortion were present in all 36 patients. Airspace consolidation was present in 33 patients (92%). The extent of areas of ground-glass attenuation (r = 0.45, P < .01) and the extent of traction bronchiectasis (r = 0.35, P < .05) correlated with disease duration. No other significant correlation was found between the CT findings and disease duration. CONCLUSION: A combination of ground-glass attenuation, airspace consolidation, traction bronchiectasis, and architectural distortion is seen in the majority of patients with acute interstitial pneumonia. The extent of ground-glass attenuation and traction bronchiectasis increases with disease duration.     

Lymphocytic interstitial pneumonia: thin-section CT findings in 22 patients.

PURPOSE: To assess the thin-section computed tomographic (CT) findings of lymphocytic interstitial pneumonia. MATERIALS AND METHODS: The study included 22 patients (five men, 17 women; age range, 24-83 years; mean age, 50 years) with biopsy-proved lymphocytic interstitial pneumonia. The CT scans were obtained by using 1-3-mm collimation and reconstructed by using a high-spatial-frequency algorithm. RESULTS: The predominant abnormalities consisted of areas of ground-glass attenuation and poorly defined centrilobular nodules present in all 22 patients and subpleural small nodules seen in 19 patients. Other common findings included thickening of bronchovascular bundles (n - 19), interlobular septal thickening (n = 18), cystic airspaces (n = 15), and lymph node enlargement (n = 15). Less common findings included large nodules, emphysema, airspace consolidation, bronchiectasis, architectural distortion, honeycombing, and pleural thickening. CONCLUSION: Lymphocytic interstitial pneumonia is characterized by the presence of ground-glass attenuation, poorly defined centrilobular nodules, and thickening of the interstitium along the lymphatic vessels. Lymph node enlargement is more common than previously recognized; it was seen in 68% of patients.