the normal chest 9, dr. muhammad bin zulfiqar

9The Normal Chest

DR MUHAMMAD BIN ZULFIQARPGR III FCPS Services institute of Medical

Sciences/ Services Hospital LahoreGRAINGER & ALLISON’S DIAGNOSTIC RADIOLOGY

• FIGURE 9-1 The position and shape of the major ■fissures (arrows) in the lower and the upper zones is best shown by CT. Note that above the hila, the major fissures bow backwards (B, C)

• The images are high-resolution 0.625-mm-thin CT sections from a 64-row multislice CT study.

• FIGURE 9-1 The position and shape of the major fissures ■(arrows) in the lower and the upper zones is best shown by CT. Note that above the hila, the major fissures bow backwards (B, C), whereas below the hila, the major fissures bow forwards (D to H).

• The images are high-resolution 0.625-mm-thin CT sections from a 64-row multislice CT study.

• FIGURE 9-1 The position and shape of the major fissures (arrows) in the ■lower and the upper zones is best shown by CT. Note below the hila, the major fissures bow forwards (D to H). The minor fissure (F, G) is apparent as an area of avascularity anterior to the major fissure. In this example the slightly bowed horizontal fissure undulates through the plane of the slice (asterisks). The images are high-resolution 0.625-mm-thin CT sections from a 64-row multislice CT study.

• The images are high-resolution 0.625-mm-thin CT sections from a 64-row multislice CT study.

• FIGURE 9-1 The position and shape of the major fissures ■(arrows) in the lower and the upper zones is best shown by CT. below the hila, the major fissures bow forwards. The minor fissure (F, G) is apparent as an area of avascularity anterior to the major fissure. In this example the slightly bowed horizontal fissure undulates through the plane of the slice (asterisks). The images are high-resolution 0.625-mm-thin CT sections from a 64-row multislice CT study.

• FIGURE 9-2 The position of fissures is often best ■shown in additional sagittal reformats (arrows) taken of the right lung (A, B) and the left lung (C, D). Note the course of the major and minor fissures together with an accessory cardiac fissure on the right (arrowhead), and the major fissure on the left (arrows).

• FIGURE 9-2 The position of fissures is often best ■shown in additional sagittal reformats (arrows) taken of the right lung (A, B) and the left lung (C, D). Note the course of the major and minor fissures together with an accessory cardiac fissure on the right (arrowhead), and the major fissure on the left (arrows).

• FIGURE 9-3 Azygos lobe fissure (A, C, arrows) and azygos ■vein (B to D, asterisk). The azygos vein in the lower end of the fissure is well seen on the coronal reformats (C, D). In the early arterial contrast perfusion phase the vein is not filled with contrast media (D) displaying a soft-tissue-like attenuation. Occasionally on conventional plain film radiography (E) the course of the azygos vein from the mediastinum to the lower end of the fissure (arrowhead) can be appreciated as a vascular band (asterisk).

• FIGURE 9-3 Azygos lobe fissure (A, C, arrows) and azygos vein ■(B to D, asterisk). The azygos vein in the lower end of the fissure is well seen on the coronal reformats (C, D). In the early arterial contrast perfusion phase the vein is not filled with contrast media (D) displaying a soft-tissue-like attenuation. Occasionally on conventional plain film radiography (E) the course of the azygos vein from the mediastinum to the lower end of the fissure (arrowhead) can be appreciated as a vascular band (asterisk).

• FIGURE 9-3 Azygos lobe fissure (A, C, arrows) and azygos vein (B to D, asterisk). ■The azygos vein in the lower end of the fissure is well seen on the coronal reformats (C, D). In the early arterial contrast perfusion phase the vein is not filled with contrast media (D) displaying a soft-tissue-like attenuation. Occasionally on conventional plain film radiography (E) the course of the azygos vein from the mediastinum to the lower end of the fissure (arrowhead) can be appreciated as a vascular band (asterisk).

• FIGURE 9-4 Intersegmental bilateral septa deep to the ■inferior pulmonary ligament (A). Note the bifurcated T-shape of the septum on the right indicating the boundaries of the segments 9 and 10 (arrowheads). The function of the inferior pulmonary ligament fixating the lower lobe to the paraoesophageal mediastinum (asterisk) is well appreciated in another patient with pneumothorax (B).

• FIGURE 9-5 Diagram illustrating the anatomy of the ■main bronchi and segmental divisions. The nomenclature is that approved by the British Thoracic Society. (Courtesy of the Editors of Thorax.)

• FIGURE 9-5 Diagram illustrating the anatomy ■of the main bronchi and segmental divisions. The nomenclature is that approved by the British Thoracic Society. (Courtesy of the Editors of Thorax.)

• FIGURE 9-6 Ring shadows (arrowheads) due to end-on ■bronchial projection as a normal finding on chest radiography. Note the delicate appearance in a patient without interstitial oedema.

RUL, 4 = lateral segment of right middle lobe (RML), 5 = medial segment of RML, 6 = apical posterior segment of left upper lobe (LUL), 7 = anterior segment of LUL, 8 = superior segment of lingula, 9 = inferior segment of lingula, 10 = apical (superior) segment of right lower lobe (RLL),

11 = medial basal segment of RLL, 12 = anterior basal segment of RLL, 13 = lateral basal segment of RLL, 14 = posterior basal segment of RLL, 15 = apical (superior) segment of left lower lobe

(LLL), 16 = anterior basal segment of LLL, 17 = lateral basal segment of LLL, 18 = posterior basal segment of LLL.

• FIGURE 9-7 Diagrams of position of segments ■seen on plain frontal and lateral chest radiographs. There is substantial overlap of the projected images of the segments in both views; this overlap is worse in the frontal than the lateral projection. (A) shows only the segments in the upper lobes and the middle lobe; (B) shows only the segments in the lower lobes; (C, D) show all the segments in the right and left lung, respectively, in the lateral view. H = hila, 1 = apical segment of right upper lobe (RUL), 2 = posterior segment of RUL, 3 = anterior segment of

• FIGURE 9-8 Pulmonary angiography. Conventional digital subtraction ■angiography using selective right and left injections (A, B). Composed image obtained during (A) the arterial phase and (B) the venous phase. Note the difference in arrangement of the central arteries and veins, whereas anatomic differences are not perceptible in the lung periphery. Also note the biventricular ICD device overlying the projection in this patient with cardiac arrhythmia. On CT pulmonary angiography the anatomical relation of arterial and venous systems can be appreciated interactively on one image using volume rendering (C) or thick-slab maximum intensity imaging (D).

• FIGURE 9-8 Pulmonary angiography. Conventional digital subtraction angiography ■using selective right and left injections (A, B). Composed image obtained during (A) the arterial phase and (B) the venous phase. Note the difference in arrangement of the central arteries and veins, whereas anatomic differences are not perceptible in the lung periphery. Also note the biventricular ICD device overlying the projection in this patient with cardiac arrhythmia. On CT pulmonary angiography the anatomical relation of arterial and venous systems can be appreciated interactively on one image using volume rendering (C) or thick-slab maximum intensity imaging (D).

• FIGURE 9-9 Diagrams of the relationships ■between the hilar blood vessels and bronchi. (A) Frontal view. (B) Right posterior oblique view of right hilum. (C) Left posterior oblique view of left hilum.

• FIGURE 9-9 Diagrams of the relationships ■between the hilar blood vessels and bronchi. (A) Frontal view. (B) Right posterior oblique view of right hilum. (C) Left posterior oblique view of left hilum.

Lateral chest radiograph with major blood vessels drawn in. IPV = inferior pulmonary vein—only one has been drawn in since they are superimposed, LPA = left pulmonary artery, LSPV = left superior pulmonary vein, RPA = right pulmonary artery, RSPV = right superior pulmonary vein. (Diagrams drawn by Ron Ervin and reproduced with permission from Armstrong P (ed) 1983 Critical problems in diagnostic radiology. Lippincott, Philadelphia.)

• FIGURE 9-9, Continued ■

• FIGURE 9-10 Normal ■digital PA chest radiograph demonstrating position and density of the hilar structures. Arrows indicate the hilar points where the superior pulmonary vein crosses the descending lower lobe artery, the left normally being level with or slightly higher than the right.

• FIGURE 9-11 Frontal view of the hila in a ■plain chest radiograph. The measurement points for the diameter of the right lower lobe artery are indicated.

• FIGURE 9-12 CT of normal hila. High-resolution CT images (0.625 mm) have been ■obtained through the hilar structures during contrast medium injection and displayed on lung windows (L-500, W 1500). (A) Section just below the tracheal carina at the origin of the right upper lobe bronchus, immediately posterior to the upper lobe vein (v). (B) Section through level of right main pulmonary artery (RPA) and bronchus intermedius (arrowhead). Note the tongue of lung that contacts the left main bronchus between the aorta (B) and the left lower lobe artery (black arrowhead). Note also that the right lung contacts the posterior wall of the bronchus intermedius as it extends into the azygo-oesophageal recess. (C) Section through the level of the middle lobe bronchus (long arrow) at the point of origin of the bronchus to the superior segment of the right lower lobe. Note that the middle lobe bronchus separates the right lower lobe artery from the right superior pulmonary vein as it enters the left atrium (LA). The lung contacts the posterior wall of the right lower lobe bronchus as it extends into the azygo-oesophageal recess. (D) Section through the level of the inferior pulmonary veins (arrows). At this level the lower lobe arteries have bilaterally divided into basal segmental divisions; each are less than 10 mm in diameter.

• FIGURE 9-12 CT of normal hila. High-resolution CT images (0.625 mm) ■have been obtained through the hilar structures during contrast medium injection and displayed on lung windows (L-500, W 1500). Section through the level of the middle lobe bronchus (long arrow) at the point of origin of the bronchus to the superior segment of the right lower lobe. Note that the middle lobe bronchus separates the right lower lobe artery from the right superior pulmonary vein as it enters the left atrium (LA). The lung contacts the posterior wall of the right lower lobe bronchus as it extends into the azygo-oesophageal recess. (D) Section through the level of the inferior pulmonary veins (arrows). At this level the lower lobe arteries have bilaterally divided into basal segmental divisions; each are less than 10 mm in diameter.

• FIGURE 9-13 Lateral view of the hila ■showing normal thickness of the posterior wall of the bronchus intermedius (arrows).

• FIGURE 9-14 MRI of normal mediastinum and hila. Four transverse and four coronal ■sections have been chosen to show the important anatomical features: (A–D, G, H) gradient echo post gadolinium iv; (E, F) T1-weighted gradient echo sequence). (A) is 1 cm above the tracheal carina; (B) is just below (A); (C) is at the level of the right main pulmonary artery; (D) is at the level of the mid left atrium. A.Ao = ascending aorta; AV = azygos vein; BI = bronchus intermedius; D.Ao = descending aorta; LA = left atrium; LCA = left carotid artery; LMB = left main bronchus; LPA = left pulmonary artery; LV = left ventricle; MPA = main pulmonary artery; Oes = oesophagus; RA = right atrium; RMB = right main bronchus; RSPV = right superior pulmonary vein; SVC = superior vena cava;

• FIGURE 9-14 MRI of normal mediastinum and hila. Four transverse and four coronal ■sections have been chosen to show the important anatomical features: (A–D, G, H) gradient echo post gadolinium iv; (E, F) T1-weighted gradient echo sequence). (A) is 1 cm above the tracheal carina; (B) is just below (A); (C) is at the level of the right main pulmonary artery; (D) is at the level of the mid left atrium. A.Ao = ascending aorta; AV = azygos vein; BI = bronchus intermedius; D.Ao = descending aorta; LA = left atrium; LCA = left carotid artery; LMB = left main bronchus; LPA = left pulmonary artery; LV = left ventricle; MPA = main pulmonary artery; Oes = oesophagus; RA = right atrium; RMB = right main bronchus; RSPV = right superior pulmonary vein; SVC = superior vena cava; T = trachea.

• FIGURE 9-14 MRI of normal mediastinum and hila. Four transverse and four ■coronal sections have been chosen to show the important anatomical features: (A–D, G, H) gradient echo post gadolinium iv; (E, F) T1-weighted gradient echo sequence). (A) is 1 cm above the tracheal carina; (B) is just below (A); (C) is at the level of the right main pulmonary artery; (D) is at the level of the mid left atrium. A.Ao = ascending aorta; AV = azygos vein; BI = bronchus intermedius; D.Ao = descending aorta; LA = left atrium; LCA = left carotid artery; LMB = left main bronchus; LPA = left pulmonary artery; LV = left ventricle; MPA = main pulmonary artery; Oes = oesophagus; RA = right atrium; RMB = right main bronchus; RSPV = right superior pulmonary vein; SVC = superior vena cava; T = trachea.

• FIGURE 9-14 MRI of normal mediastinum and hila. Four transverse and four ■coronal sections have been chosen to show the important anatomical features: (A–D, G, H) gradient echo post gadolinium iv; (E, F) T1-weighted gradient echo sequence). (A) is 1 cm above the tracheal carina; (B) is just below (A); (C) is at the level of the right main pulmonary artery; (D) is at the level of the mid left atrium. A.Ao = ascending aorta; AV = azygos vein; BI = bronchus intermedius; D.Ao = descending aorta; LA = left atrium; LCA = left carotid artery; LMB = left main bronchus; LPA = left pulmonary artery; LV = left ventricle; MPA = main pulmonary artery; Oes = oesophagus; RA = right atrium; RMB = right main bronchus; RSPV = right superior pulmonary vein; SVC = superior vena cava; T = trachea.

• FIGURE 9-15 CT of normal mediastinum. (A–I) Five 1-cm-thick ■sections have been selected to show the important anatomical features. The level of each section is illustrated in the diagram. A.Ao = ascending aorta; AoA = aortic arch; AV = azygos vein; D.Ao = descending aorta; IA = innominate artery; LA = left atrium; LCA = left carotid artery; LIV = left innominate vein; LPA = left pulmonary artery; LSA = left subclavian artery; MPA = main pulmonary artery; OES = oesophagus; RA = right atrium; RIV = right innominate vein; RPA = right pulmonary artery; RVO = right ventricular outflow tract; SPV = superior pulmonary vein; SVC = superior vena cava; T = trachea.

• FIGURE 9-15 CT of normal mediastinum. (A–I) Five 1-cm-thick ■sections have been selected to show the important anatomical features. The level of each section is illustrated in the diagram. A.Ao = ascending aorta; AoA = aortic arch; AV = azygos vein; D.Ao = descending aorta; IA = innominate artery; LA = left atrium; LCA = left carotid artery; LIV = left innominate vein; LPA = left pulmonary artery; LSA = left subclavian artery; MPA = main pulmonary artery; OES = oesophagus; RA = right atrium; RIV = right innominate vein; RPA = right pulmonary artery; RVO = right ventricular outflow tract; SPV = superior pulmonary vein; SVC = superior vena cava; T = trachea.

• FIGURE 9-15 CT of normal mediastinum. (A–I) Five 1-cm-thick ■sections have been selected to show the important anatomical features. The level of each section is illustrated in the diagram. A.Ao = ascending aorta; AoA = aortic arch; AV = azygos vein; D.Ao = descending aorta; IA = innominate artery; LA = left atrium; LCA = left carotid artery; LIV = left innominate vein; LPA = left pulmonary artery; LSA = left subclavian artery; MPA = main pulmonary artery; OES = oesophagus; RA = right atrium; RIV = right innominate vein; RPA = right pulmonary artery; RVO = right ventricular outflow tract; SPV = superior pulmonary vein; SVC = superior vena cava; T = trachea.

• FIGURE 9-15 CT of normal mediastinum. (A–I) Five 1-cm-thick ■sections have been selected to show the important anatomical features. The level of each section is illustrated in the diagram. A.Ao = ascending aorta; AoA = aortic arch; AV = azygos vein; D.Ao = descending aorta; IA = innominate artery; LA = left atrium; LCA = left carotid artery; LIV = left innominate vein; LPA = left pulmonary artery; LSA = left subclavian artery; MPA = main pulmonary artery; OES = oesophagus; RA = right atrium; RIV = right innominate vein; RPA = right pulmonary artery; RVO = right ventricular outflow tract; SPV = superior pulmonary vein; SVC = superior vena cava; T = trachea.

• FIGURE 9-15 CT of normal mediastinum. (A–I) Five 1-cm-thick ■sections have been selected to show the important anatomical features. The level of each section is illustrated in the diagram. A.Ao = ascending aorta; AoA = aortic arch; AV = azygos vein; D.Ao = descending aorta; IA = innominate artery; LA = left atrium; LCA = left carotid artery; LIV = left innominate vein; LPA = left pulmonary artery; LSA = left subclavian artery; MPA = main pulmonary artery; OES = oesophagus; RA = right atrium; RIV = right innominate vein; RPA = right pulmonary artery; RVO = right ventricular outflow tract; SPV = superior pulmonary vein; SVC = superior vena cava; T = trachea.

• FIGURE 9-16 CT of normal thymus (arrow) ■in a young adult man.

• FIGURE 9-17 Thymic residues (curved ■arrows) shown by CT.

• FIGURE 9-18 The International Association for the Study of ■Lung Cancer (IASLC) lymph node map grouping the lymph node stations into ‘zones’ for purpose of prognostic analysis (from: <http://www.radiologyassistant.nl/en/4646f1278c26f>). Please see explanations in Table 9-1.

• FIGURE 9-18 The International Association for the Study of ■Lung Cancer (IASLC) lymph node map grouping the lymph node stations into ‘zones’ for purpose of prognostic analysis (from: <http://www.radiologyassistant.nl/en/4646f1278c26f>). Please see explanations in Table 9-1.

• FIGURE 9-19 The IASLC lymph node map can be applied to clinical staging by computed ■tomography in axial (A–C) views. The border between the right and left paratracheal region is shown in (A) and (B). Ao = aorta; Az = azygos vein; MB = main bronchus; Eso = oesophagus; IV = innominate vein; LtInV = left innominate vein; LtSCA = left subclavian artery; PA = pulmonary artery; SPV = superior pulmonary vein; RtInV = right innominate vein; SVC = superior vena cava; T = trachea. (With permission from Rusch VW, Asamura H, Watanabe H et al 2009 The IASLC lung cancer staging project. J Thorac Oncol 4: 568–577.)

• FIGURE 9-19 The IASLC lymph node map can be applied to clinical staging by computed ■tomography in axial (A–C) views. The border between the right and left paratracheal region is shown in (A) and (B). Ao = aorta; Az = azygos vein; MB = main bronchus; Eso = oesophagus; IV = innominate vein; LtInV = left innominate vein; LtSCA = left subclavian artery; PA = pulmonary artery; SPV = superior pulmonary vein; RtInV = right innominate vein; SVC = superior vena cava; T = trachea. (With permission from Rusch VW, Asamura H, Watanabe H et al 2009 The IASLC lung cancer staging project. J Thorac Oncol 4: 568–577.)

• FIGURE 9-20 Diagrams ■illustrating the mediastinal boundaries and junction lines. The visualisation of the junction lines on a plain chest radiograph is variable, depending on how much fat is present in the mediastinum and on how closely the two lungs approximate to one another. (A) Section just above the level of the aortic arch; (B) section through the aortic arch; (C) section through the heart. (D) Axial CT and (E) chest plain X-ray showing the anterior junction line (arrowheads). (F, G) Axial CT showing the supra-aortic and lower posterior junction line (arrows).

• FIGURE 9-20 Diagrams illustrating the mediastinal boundaries ■and junction lines. The visualisation of the junction lines on a plain chest radiograph is variable, depending on how much fat is present in the mediastinum and on how closely the two lungs approximate to one another. (A) Section just above the level of the aortic arch; (B) section through the aortic arch; (C) section through the heart. (D) Axial CT and (E) chest plain X-ray showing the anterior junction line (arrowheads). (F, G) Axial CT showing the supra-aortic and lower posterior junction line (arrows).

• FIGURE 9-20 Diagrams illustrating the mediastinal boundaries and ■junction lines. The visualisation of the junction lines on a plain chest radiograph is variable, depending on how much fat is present in the mediastinum and on how closely the two lungs approximate to one another. (A) Section just above the level of the aortic arch; (B) section through the aortic arch; (C) section through the heart. (D) Axial CT and (E) chest plain X-ray showing the anterior junction line (arrowheads). (F, G) Axial CT showing the supra-aortic and lower posterior junction line (arrows).

• FIGURE 9-20 Diagrams illustrating the mediastinal boundaries and ■junction lines. The visualisation of the junction lines on a plain chest radiograph is variable, depending on how much fat is present in the mediastinum and on how closely the two lungs approximate to one another. (A) Section just above the level of the aortic arch; (B) section through the aortic arch; (C) section through the heart. (D) Axial CT and (E) chest plain X-ray showing the anterior junction line (arrowheads). (F, G) Axial CT showing the supra-aortic and lower posterior junction line (arrows).

• FIGURE 9-21 Right tracheal stripe (straight ■arrows) and pleurooesophageal line (curved arrows) demonstrated on (A) plain radiograph and (B) unenhanced CT.

• FIGURE 9-22 Lateral view of trachea and ■major bronchi. (A) In this example, the posterior wall of the trachea is outlined by lung posterior to it (arrow). (B) In this example, the collapsed oesophagus is between the lung and the trachea (arrow).

• FIGURE 9-23 Bulge behind manubrium ■representing normal left innominate (brachiocephalic) vein (arrow).

• FIGURE 9-24 Azygo-oesophageal line ■(arrows).

• FIGURE 9-25 Patterns of pleural reflection along the left ■border of the great vessels and heart. The heavy line indicates the visible pleural interface. (Adapted from Blank N, Castellino R A 1972 Patterns of pleural reflections of the left superior mediastinum: normal anatomy and distortions produced by adenopathy. Radiology 102: 585–589, with permission from the Radiological Society of North America.)

• FIGURE 9-26 Retrosternal stripe ■(arrowheads) and inferior vena cava in lateral projection (arrows).

• FIGURE 9-27 (A) Right phrenic nerve as it passes ■over the surface of the right hemidiaphragm (arrows). (B, C) Coronal secondary reformat and volume rendering showing the nerve as delicate structure crossing a lymph node in the mediastino-diaphragmatic angle (arrowheads).

• FIGURE 9-27 (A) Right phrenic nerve as it passes ■over the surface of the right hemidiaphragm (arrows). (B, C) Coronal secondary reformat and volume rendering showing the nerve as delicate structure crossing a lymph node in the mediastino-diaphragmatic angle (arrowheads).