FIGURE 9-1. Association between the lung, pleura, and chest wall. The lungs are invested in the visceral pleura, whereas the parietal pleura lines the ribs and soft tissues of the chest wall, diaphragm, and mediastinum. The parietal pleura is separated from the ribs and intercostal muscles by fat and endothoracic fascia. The total thickness of the pleura and "potential" pleural space is only 0.2 to 0.4 mm.
FIGURE 9-2. Radiologic pleural-based densities. A pleural-based density has margins that are partially or completely well circumscribed, indicating contiguity with a pleural surface. There are five types of pleural-based densities, depending on the location of origin. An extrapleural densityoriginates in the chest wall, and when it does not extend into the pleura and lung, it has a sharp medial margin where it contacts the parietal pleura. When the adjacent rib is involved, rib fracture with hematoma or neoplasm should be considered. Parietaland visceral pleural densitiesare usually asbestos-related pleural plaques, which may or may not be calcified. Interpleural densitiesmost commonly represent loculated pleural effusions; when intrafissural in location they may be recognized on chest radiography by characteristic "beaking" at the ends of the fluid collection where the pleural layers of a fissure meet (producing a "pseudotumor"). Subpleural densitiesare parenchymal and usually have an indistinct lung parenchymal margin. If the lesion extends into the pleura and chest wall, all the margins of the lesion may be indistinct. Etiologies to consider when a subpleural density involves the pleura or chest wall are neoplasm and infection (especially fungal, mycobacterial, and actinomycotic).
FIGURE 9-3. Subpleural squamous cell bronchogenic carcinoma. A: Posteroanterior (PA) chest radiograph of a 67-year-old woman shows a mass in the left upper hemithorax (arrows) that is contiguous with the pleural surface. B: CT with lung windowing shows the mass abutting the lateral pleural surface and major fissure. C: CT with mediastinal windowing shows that the mass is contiguous with the pleural surface. Centrally, the mass contains areas of low attenuation, consistent with necrosis.
TABLE 9-1 COMMON CAUSES OF PLEURAL EFFUSION
FIGURE 9-4. Pancoast tumor. PA (A) and lateral (B) chest radiographs of a 61-year-old man with right shoulder pain and a 40–pack-year history of cigarette smoking shows a circumscribed mass (arrow) in the right apex. C: CT with bone windowing shows the mass filling the right lung apex and destruction of the right second rib (arrow).
FIGURE 9-5. Cerebrospinal fluid leak into pleural space. A: PA chest radiograph of a 42-year-old man who recently underwent partial corpectomy of the thoracic spine at several levels shows complete opacification of the right hemithorax and shift of the mediastinum to the left. B: Non–contrast-enhanced CT shows a large right pleural effusion, collapse of the right lung, mediastinal shift to the left, findings of corpectomy, and continuity of fluid from the spine into the pleural space (arrow).
FIGURE 9-6. Pleural and pericardial effusions. A: PA chest radiograph of a woman with hypothyroidism shows blunting of the right costophrenic angle, producing a "meniscus" (arrow). B: Lateral chest radiograph shows blunting of both costophrenic angles posteriorly (arrow). C: CT shows bilateral pleural and pericardial effusions (E).
FIGURE 9-7. Pulmonary edema and pleural fluid pseudotumor. A: PA chest radiograph shows enlargement of the cardiac silhouette, interstitial pulmonary edema, and displacement of the inferolateral lungs from the chest wall and diaphragm by pleural effusion (straight arrows). There is a hazy "mass" in the left middle and lower hemithorax (curved arrows). B: Lateral chest radiograph shows that the "mass" or "pseudotumor" (curved arrows) blends in with the left major fissure (straight arrows); this is characteristic of pleural fluid within the fissure. The superior aspect of the left major fissure is thickened as a result of pleural fluid and subpleural edema (arrowheads).
FIGURE 9-8. Pleural fluid pseudotumor. A: PA chest radiograph shows a circumscribed ovoid mass in the right lower hemithorax (solid arrows) and thickening of the minor fissure (dashed arrow). B: Lateral view shows that the mass (arrows) is oriented in the direction of and superimposed on the major fissure. C: CT (bone windowing) shows that the mass is of fluid attenuation, representing pleural effusion (E), and is contiguous with the thickened major fissure (arrow).
FIGURE 9-9. Positional appearances of pleural fluid on chest radiography and CT. A: PA upright chest radiograph shows apparent elevation of the right hemidiaphragm. The dome of the right hemidiaphragm appears to be displaced laterally (arrow), a clue to the diagnosis of pleural fluid collecting in a "subpulmonic" location. B: Anteroposterior (AP) supine chest radiograph of the same patient, 3 days later, shows hazy increased opacification of the right hemithorax secondary to pleural fluid layering posteriorly within the pleural space, now the most gravity-dependent portion of the pleural space. C: AP semi-upright chest radiograph of the same patient, 2 days after (B), shows a combination of pleural fluid layering posteriorly, which produces a hazy opacity in the mid and lower right hemithorax and laterally (arrows). D: Right lateral decubitus chest radiograph of the same patient, taken on the same day as (A), shows pleural fluid freely layering against the now gravity-dependent lateral chest wall, from the costophrenic angle to the lung apex (arrows). E: CT of the same patient, performed on the same day as (B), shows a moderate- to large-sized right pleural fluid collection (E), with associated "passive" atelectasis of the right lower lobe (A).
FIGURE 9-10. Hemothorax. CT shows high-attenuation blood (H) in the right pleural space.
FIGURE 9-11. Malignant pleural effusion. A: PA chest radiograph of a 62-year-old woman with metastatic breast cancer who has had a right mastectomy and axillary node dissection (note surgical clips in right axilla; arrows) shows apparent elevation of the right hemidiaphragm. B: Lateral chest radiograph also shows apparent elevation of the right hemidiaphragm (arrows). The left hemidiaphragm is easily identified (arrowheads), as it is just superior to the stomach bubble. C: CT shows a large right pleural effusion (E) and metastatic breast cancer infiltrating the right chest wall (arrows). D: CT at a level inferior to (C) shows a metastatic soft tissue mass to the mediastinal pleura (arrow) and thickening of the mediastinal pleura (arrowheads).
TABLE 9-2 CAUSES OF A LARGE UNILATERAL PLEURAL EFFUSION
FIGURE 9-12. Re-expansion pulmonary edema. A: PA chest radiograph of a 78-year-old woman with metastatic breast cancer shows a large left pleural effusion associated with collapse of the left lung and shift of the mediastinum to the right. These findings suggest tension hydrothorax. B: PA chest radiograph after placement of a left chest tube and adequate drainage of pleural fluid shows re-expansion pulmonary edema on the left.
FIGURE 9-13. Tuberculous empyema. PA chest radiograph shows a large left pleural effusion. A large unilateral pleural effusion is worrisome for empyema, hemothorax, malignancy, or chylothorax.
FIGURE 9-14. Empyema. A: PA chest radiograph of a 60-year-old man with right lower lobe pneumonia shows a large right hydropneumothorax with air–fluid level. There is an incidental calcified granuloma in the right mid lung. B: CT shows a round collection of air and fluid in the right pleural space. The thickened and enhancing separated pleural layers create the "split pleura" sign. Air within an empyema can be secondary to thoracentesis, bronchopleural fistula, or, rarely, a gas-forming organism.
FIGURE 9-15. Empyema. A: PA chest radiograph of a 55-year-old man shows a large left pleural effusion, compression of the upper lung, and collapse of the lower lung. B: CT shows an elongated ovoid collection of fluid in the left pleural space and collapse of the adjacent lung.
FIGURE 9-16. Malignant pleural effusion. A: PA chest radiograph of an 83-year-old woman with metastatic right breast cancer shows a large right pleural effusion and interstitial lung disease. B: CT after drainage of right pleural fluid shows nodular thickening of the vascular structures and pulmonary septae on the right, characteristic of lymphangitic carcinomatosis.
FIGURE 9-17. Malignant pleural effusion. A: PA chest radiograph of a 57-year-old man with metastatic esophageal carcinoma who had undergone esophagectomy and gastric pull-through shows a lobulated opacity in the left upper hemithorax. B: CT shows loculated pleural fluid (E) extending into the fissure. There is fluid in the intrathoracic stomach (arrow).
FIGURE 9-18. Malignant mesothelioma. PA chest radiograph of a 53-year-old man shows right pleural opacification with a lobulated contour that involves the entire pleural surface (arrows) and is associated with a "fixed mediastinum," meaning no shift right or left, and ipsilateral loss of lung volume, characteristic of malignant mesothelioma.
FIGURE 9-19. Malignant mesothelioma. A: PA chest radiograph of a 69-year-old man who worked at a manufacturing plant making brake linings and asbestos shingles shows a large unilateral right pleural effusion. B: CT shows thickening of the entire pleural surface (arrows). C: CT scan at a level inferior to (B) shows a large right pleural effusion (E) and thickening and enhancement of the parietal (arrows) and visceral (arrowhead) pleura.
FIGURE 9-20. Malignant mesothelioma. A: PA chest radiograph of a 43-year-old man shows a large right pleural effusion with thickening of the minor fissure (arrows). B: CT shows that the pleural effusion is of higher attenuation compared with simple fluid (consistent with tumor within the pleural space); wraps around the entire pleural surface, including the fissure (arrows); and has a lobulated contour.
TABLE 9-3 CAUSES OF PNEUMOTHORAX IN ADULTS
FIGURE 9-21. Spontaneous secondary pneumothorax. PA chest radiograph of an 18-year-old man with cystic fibrosis shows a large right hydropneumothorax and severe bilateral cystic bronchiectasis.
FIGURE 9-22. Spontaneous secondary pneumothorax. AP chest radiograph of a 3-year-old boy with respiratory syncytial virus pneumonia shows a large left pneumothorax with shift of the mediastinum to the right. The findings suggest a tension pneumothorax. Numerous cystic lesions, consistent with pneumatoceles, are seen in the collapsed left lung (arrow).
FIGURE 9-23. Skin fold mimicking pneumothorax. A: AP supine chest radiograph shows opacification of the right medial lung outlined by a sharp edge (skin fold; arrows). Note that the lung peripheral to this edge is not hyperlucent, a clue that there is no pneumothorax. B: AP upright chest radiograph obtained 1 hour later no longer shows the skin fold. Redundant skin can result in skin folds on the chest radiograph, especially when the patient is supine. Changing patient positioning is often useful in differentiating a skin fold from a pneumothorax.
FIGURE 9-24. Pneumothorax in a supine patient. AP supine chest radiograph shows the "deep sulcus" sign of pneumothorax on the right (curved arrow) and a basilar pneumothorax on the left (straight arrows).
TABLE 9-4 RADIOGRAPHIC SIGNS OF PNEUMOTHORAX IN THE SUPINE PATIENT
FIGURE 9-25. Tension pneumothorax. AP supine chest radiograph of a 35-year-old man involved in a motor vehicle crash shows a large left pneumothorax, collapse of the left lung, and shift of the mediastinum to the right. The findings suggest a tension pneumothorax, which requires immediate decompression.
FIGURE 9-26. Malignant mesothelioma. CT scan of a 59-year-old man shows a solitary focal enhancing left pleural soft tissue lesion (arrow). At surgery, multiple additional lesions were seen studding the pleural surface.
FIGURE 9-27. Benign localized fibrous tumor of the pleura. A: PA chest radiograph of a 32-year-old asymptomatic woman shows a well-circumscribed round mass in the left middle lung (arrows). B: Lateral view shows that the mass is positioned adjacent to the left major fissure (arrows). C: PA chest radiograph obtained 4 years later shows that the mass has increased in size. Faint calcification is now visible within the mass (arrow). D: Lateral view obtained at the same time as (C). E: CT shows that the mass is homogeneous, abuts the lateral pleural surface, and has coarse calcifications (arrows). F: CT with lung windowing shows that the top of the tumor abuts the major fissure (arrows).
FIGURE 9-28. Pleural lipoma. A: PA chest radiograph coned to the right upper lobe shows a circumscribed mass (arrows) contiguous with the right lateral chest wall. B: CT shows that the mass (arrow) is of homogeneous fat attenuation (F).
FIGURE 9-29. Benign pleural myelolipoma. CT of a 66-year-old woman shows a circumscribed mass abutting the left lateral chest wall. Although the mass contains central fat (arrow), the attenuation of the mass is heterogeneous, and a malignancy, such as liposarcoma, cannot be excluded. The mass was excised and found to be benign.
FIGURE 9-30. Old tuberculous empyema. A: PA chest radiograph shows dense calcification throughout the right hemithorax. B: Chest radiograph with dual energy, to emphasize the bones and calcium, optimally shows the long linear calcifications in the right hemithorax. C: CT shows dense pleural calcifications (arrows) involving only the right hemithorax, associated with loss of lung volume. [AU/PRODUCTION: Note that 9-30B should be a chest radiograph; what is labeled as 9-30B appears to in fact be 9-30C, and 9-30B is missing.]
FIGURE 9-31. Calcified pleural and pericardial plaques. CT of an 82-year-old man with prior asbestos exposure shows calcified pericardial (solid arrow) and pleural (dashed arrow) plaques, in addition to diffuse pleural thickening and rounded atelectasis (R).
FIGURE 9-32. Pectus excavatum. A: PA chest radiograph of a 60-year-old man shows blurring of the right heart border and displacement of the mediastinum to the left. B: Lateral view shows posterior depression of the sternum (arrow).
FIGURE 9-33. Lymphoma with rib involvement. A: PA chest radiograph shows a circumscribed mass (arrows) that is contiguous with the upper right lateral chest wall. B: CT shows the mass (arrow) and destruction of the right second rib.
FIGURE 9-34. Actinomycosis of the chest wall. A: PA chest radiograph of a 58-year-old man with a 1-month history of shortness of breath and poor oral hygiene shows airspace disease in the left upper lobe. B: Lateral view shows extension of the left upper lobe pneumonia into the anterior chest wall. There is air within the swollen soft tissues of the chest wall (arrows). C: CT shows extension of the left upper lobe pneumonia into the anterior chest wall, along with numerous bubbles of air within the chest wall (arrows).
FIGURE 9-35. Tuberculous pneumonia with broncho-pleural-cutaneous fistula. A: AP upright chest radiograph of an 83-year-old woman with a history of left mastectomy and cobalt radiotherapy 30 years prior, along with a remote history of positive skin test for tuberculosis that was treated with appropriate drug therapy. Now, with a draining left chest wall wound at the surgical scar site, the patient's chest radiograph shows a cavitary mass in the left upper lobe (arrows) and scarring in the right upper lobe (unchanged compared with prior chest radiographs). B: CT shows air from the cavity communicating with the pleura and skin of the anterior chest wall (arrows), so-called empyema necessitatis. Analysis of the fluid draining from the chest wall revealed Mycobacterium tuberculosis. The patient was predisposed to the development of reactivation tuberculosis because she had recently been taking high doses of steroids to treat polymyalgia rheumatica.
FIGURE 9-36. Chondrosarcoma of the sternum. A: PA chest radiograph of a 67-year-old woman shows a large area of opacification in the right lower hemithorax, a right pleural effusion (arrows), and shift of the mediastinum to the left. B: Lateral view shows amorphous calcifications overlying the anterior heart (smaller arrows), a large mass within the anterior mediastinum (larger arrows), and a pleural effusion (curved arrows). C: CT, with patient prone, shows a calcified mass arising from the sternum (arrows) and a loculated right malignant pleural effusion (E) extending into the major fissure (F). Differential diagnosis included malignant teratoma, malignant thymoma, and osteogenic sarcoma.
FIGURE 9-37. Sternal metastases. CT of a 64-year-old woman with metastatic endometrial carcinoma shows complete destruction of the sternum by a large soft tissue mass with punctate and curvilinear calcifications.
FIGURE 9-38. Aneurysmal bone cyst of the left chest wall. A: PA chest radiograph of a 19-year-old asymptomatic man with a history of Hodgkin disease treated with chemotherapy and radiation shows a circumscribed mass projecting over the left upper lobe and contiguous with the left upper chest wall. B: CT with bone windowing shows that the destructive mass arises from the left upper ribs. C: CT at a level inferior to (B) shows that the mass contains areas of dense calcification. The appearance of this new mass on routine chest radiography was suspicious for a radiation-induced sarcoma.
FIGURE 9-39. Benign rib osteochondroma. A: PA chest radiograph of a 20-year-old man shows a calcified mass arising form a lower right lateral rib (arrow). B: CT shows continuity of the cortex and marrow of the osteochondroma with that of the host rib, as well as characteristic extension of the osteochondroma on a stalk with a cauliflowerlike head.
FIGURE 9-40. Sternal wound infection. CT scan of a 47-year-old man several weeks after coronary artery bypass grafting shows an air–fluid level (solid arrow) and a focal fluid collection (dashed arrow) in the presternal soft tissues and abnormal areas of high attenuation in the retrosternal area. Bacterial infection was confirmed during surgical debridement.
TABLE 9-5 MASSES INVOLVING THE CHEST WALL
FIGURE 9-41. Foramen of Morgagni hernia. A: PA chest radiograph of an 11-year-old girl shows an abnormal right mediastinal contour (arrows) and loss of the normal right heart border. B: CT shows fat and prominent omental vascular structures anterior to the heart. C: Sagittal T1-weighted magnetic resonance image shows a defect in the anterior diaphragm (arrow) and herniation of high-signal fat (F) into the anterior chest.
FIGURE 9-42. Elevated diaphragm secondary to subdiaphragmatic splenic hematoma. A: AP upright chest radiograph of a 68-year-old man with left flank pain and chronic lymphocytic lymphoma shows elevation of the left hemidiaphragm (arrows). B: CT shows a large subcapsular splenic hematoma (straight arrows). The high-attenuation material within the hematoma represents acute bleeding (curved arrow). C: CT at a level inferior to (B) shows multiple low-attenuation areas within the spleen from spontaneous splenic rupture (straight arrows) and high-attenuation material from acute bleeding (curved arrow).
FIGURE 9-43. Elevated diaphragm secondary to hepatic hemangioma. A: CT scout image shows elevation of the right hemidiaphragm. B: Axial CT shows a large hepatic mass.
FIGURE 9-44. Bronchogenic carcinoma invading the phrenic nerve. A: PA chest radiograph of a 74-year-old woman shows normal positioning of the hemidiaphragms. B: PA chest radiograph obtained 1 year later shows elevation of the right hemidiaphragm and no evidence of mediastinal mass. C: CT shows a homogeneous soft tissue mass adjacent to the superior vena cava (arrows), which proved to be a bronchogenic adenocarcinoma invading the right phrenic nerve. This case illustrates the significance of new diaphragmatic elevation in an adult, even when no mediastinal mass is seen on the chest radiograph.
TABLE 9-6 UNILATERAL ELEVATED DIAPHRAGM