Pathologies of the airspace disease.pptx

Interesting presentation on the pathologies of the air spaces

1. AIR SPACE DISEASES Dr CHUBAKA BISHIKWABO FRANCK RAD. RESIDENT 2.1 TUTOR: Dr MOSES ACAN

2. The term air space refers to bronchioles, alveolar ducts and alveoli. Terminal bronchioles and other airways that are only conductives are excluded

3. DEFINITION: Any pathological process that displaces air from the alveoli will be depicted as airspace opacification WHAT FILLS THE AIRSPACES IN AIRSPACE DISEASE? f luid Pus Blood Cells

4. Characteristics of airspace disease Produces opacities in the lung that can be described as fluffy, cloudlike, and hazy. The opacities tend to be confluent, merging into one another. The margins of airspace disease are fuzzy and indistinct. Air bronchograms /silhouette sign may be present.

5. Air bronchogram • The visibility of air in the bronchus because of surrounding airspace disease is called an air bronchogram. An air bronchogram is a sign of airspace disease. Bronchi are normally not visible because their walls are very thin, they contain air, and they are surrounded by air. When something like fluid or soft tissue replaces the air normally surrounding the bronchus, then the air inside of the bronchus becomes visible

6. The silhouette sign The silhouette sign occurs when two objects of the same radiographic density (such as water and soft tissue)touch each other so that the edge or margin between them disappears. It will be impossible to tell where one object begins and the other ends.

7. … Right Middle Lobe Mass. On the frontal image, there is a large mass in the right lower lung field. We note it is "silhouetting" the right heart border (red arrow) which is no longer seen as a distinct edge. It is not silhouetting the right hemidiaphragm (black arrow). The mass is therefore (1) touching the right heart border and is anterior and (2) the mass is soft tissue or fluid density. The lateral view shows the mass (M) is in the right middle lobe. It was a large bronchogenic carcinoma.

8. Radiological Signs of Airspace Disease N odular pattern G round-glass opacification C onsolidation.

9. A nodular pattern as a sole manifestation of airspace disease is relatively uncommon. ‘ A cinar nodules’ or ‘acinar rosettes’ has been used to describe the appearance of poorly defined infiltrates on chest radiography and HRCT B acterial infection or pulmonary haemorrhage NODULAR PATTERN

10. Ground-glass opacity (GGO) represents: Filling of the alveolar spaces with pus, edema, hemorrhage, inflammation or tumor cells. Thickening of the interstitium or alveolar walls below the spatial resolution of the HRCT as seen in fibrosis. So ground-glass opacification may either be the result of air space disease (filling of the alveoli) or interstitial lung disease (i.e. fibrosis). On plain radiography - hazy increased lung opacity with the margins of pulmonary vessels may be indistinct o n CT appears as a hazy increase in lung attenuation but without obscuration of bronchial and vascular markings

11. T he location of the abnormalities in ground glass pattern can be helpful: Upper zone predominance : Respiratory bronchiolitis, Pneumocystis pneumonia. Lower zone predominance : UIP, NSIP, DIP. Centrilobular distribution : Hypersensitivity pneumonitis, Respiratory bronchiolitis

12. Consolidation I ncrease in lung density on chest radiography or CT in which the margins of vessels and airways are obscured An air bronchogram may be seen.

13. P athologic processes can result in air-space consolidation : 1. Water (e.g., the various types of pulmonary edema) 2. Blood (e.g., pulmonary hemorrhage) 3. Pus (e.g., pneumonia) 4. Cells (e.g., pulmonary adenocarcinoma, lymphoma, eosinophilic pneumonia, organizing pneumonia [OP]) 5. Other substances (e.g., lipoprotein in alveolar proteinosis, lipid in lipoid pneumonia

14. CONSOLIDATION Acute Pneumonia Pulmonary alveolar edema Hemorrhage Acute eosinophilic pneumonia Chronic Bronchoalveolar cell carcinoma Alveolar cell proteinosis Aspiration Near-drowning Sarcoidosis Lymphoma Chronic eosinophilic pneumonia Fibrosis in UIP and NSIP

15. Radiographic and CT Findings of Consolidation Homogeneous opacity obscuring vessels Air bronchograms Ill-defined or fluffy opacities “Air alveolograms ” Patchy opacities “Acinar” or air-space nodules Preserved lung volume Extension to pleural surface “CT angiogram” sign

16. Homogeneous Opacity Obscuring Vessels With complete replacement of alveolar air, homogeneous opacification of the lung results. Vessels within the consolidated lung are invisible

17. Enhanced CT in a patient with right middle and lower lobe pneumonia shows homogeneous consolidation, preserved lung volume, air bronchograms (black arrows), and opacified vessels (white arrows), appearing denser than surrounding consolidated lung (i.e., the “CT angiogram” sign).Preserved Lung Volume In the presence of consolidation, because alveolar air is replaced by something else the volume of affected lung tends to be preserved

18. : Ill-defined fluffy consolidation (white arrows) is visible on CT in a patient with right lower lobe pneumonia. Small focal lucencies (black arrows) within the area of consolidation are “air alveolograms .”

19. Consolidation: patchy opacities. A : Chest radiograph in a patient with pulmonary edema due to renal failure shows patchy perihilar consolidation. B : Patchy areas of fluffy consolidation are seen on CT. The fluffy margins are due to variable involvement of alveoli at the edges of the pathologic process.

20. Patterns of Consolidation Diffuse or Extensive Consolidation . Water (Edema) Hydrostatic (cardiogenic) pulmonary edema Increased permeability (noncardiogenic) pulmonary edema Blood (hemorrhage) Aspiration of blood Bleeding diathesis Collagen-vascular disease and immune complex vasculitis Goodpasture's syndrome Idiopathic pulmonary hemosiderosis Trauma Vasculitis Other substances Alveolar proteinosis (lipoprotein) Lipoid pneumonia (lipid) Cells Neoplasm - Pulmonary adenocarcinoma Lymphoma and other lymphoproliferative diseases Eosinophilic pneumonia or other eosinophilic diseases Organizing pneumonia (OP) Idiopathic interstitial pneumonias Sarcoidosis

21. Perihilar “Bat-Wing” Consolidation S hows central consolidation with sparing of the lung periphery P ulmonary edema This pattern also may be seen with : pulmonary hemorrhage pneumonias (including bacteria and atypical pneumonias such as Pneumocystis jiroveci pneumonia [PCP] and viral pneumonia) inhalational lung injury.

22. Peripheral or subpleural consolidation is the opposite of a bat-wing pattern (i.e., a reverse bat wing pattern). Consolidation is seen adjacent to the chest wall, with sparing of the perihilar regions. It is classically associated with eosinophilic lung diseases, particularly eosinophilic pneumonia but may also occur with OP, sarcoidosis, radiation pneumonitis, lung contusion, or mucinous adenocarcinoma. Peripheral or Subpleural Consolidation

23. Peripheral subpleural (reverse bat-wing) consolidation. A: Chest radiograph in a patient with chronic eosinophilic pneumonia shows areas of consolidation in the subpleurallung . The perihilar regions are spared. B: CT in a patient with OP shows patchy areas of consolidation in the subpleural lung.

24. Diffuse Patchy Consolidation seen with any pneumonia (bacterial, mycobacterial, fungal, viral, PCP), pulmonary edema (hydrostatic and permeability), acute respiratory distress syndrome (ARDS), pulmonary hemorrhage aspiration, inhalational diseases eosinophilic diseases invasive mucinous adenocarcinoma. .

25. Diffuse Air-space Nodules This appearance is seen in patients with endobronchial spread of infection such as : T uberculosis (TB) or Mycobacterium avium complex (MAC) bacterial bronchopneumonia viral pneumonia (cytomegalovirus [CMV], measles) invasive mucinous adenocarcinoma with endobronchial spread pulmonary hemorrhage aspiration.

26. 4. Diffuse air-space nodules in bronchopneumonia. Multiple small nodular opacities are typical of spread of infection through the airways. This represented a bacterial bronchopneumonia, but other organisms such as TB, MAC, fungus, or viruses may be involved.

27. Diffuse Homogeneous Consolidation P ulmonary edema, ARDS P ulmonary hemorrhage P neumonias (including viral and PCP) A lveolar proteinosis E xtensive atelectasis.

28. Differential Diagnosis of Focal Consolidation Water (Edema) Edema in a patient with Pulmonary artery obstruction (e.g., pulmonary embolism) Pulmonary vein occlusion Atelectasis with drowned lung Cells Neoplasm Pulmonary adenocarcinoma Lymphoma and other lymphoproliferative diseases Eosinophilic pneumonia or other eosinophilic diseases Organizing pneumonia (OP) Sarcoidosis Pus (pneumonia) Bacterial Tuberculosis or nontuberculous mycobacterial Fungal Virus (uncommon) Pneumocystis (uncommon) Aspiration pneumonia Atelectasis with postobstructive pneumonia Blood (hemorrhage) Contusion Infarction Aspiration of blood Vasculitis

29. Lobar Consolidation Consolidation involving a single (or more than one) lobe is most typical of pneumonia (including Streptococcus pneumoniae , Klebsiella , Legionella, and TB) and abnormalities associated with bronchial obstruction. Consolidation can be localized to one or more lobes if its relationship to a specific fissure or fissures is apparent on either frontal or l ateral radiographs, or on CT.

30. . Lobar consolidation with expansion. A: A patient with right upper lobe consolidation due to Klebsiella pneumonia shows downward bowing of the minor fissure (arrows) because of lobar expansion. B: Invasive mucinous adenocarcinoma involving the left upper lobe with posterior bulging (arrows) of the left major fissure.

31. Segmental (or Subsegmental ) Consolidation Segmental (or subsegmental ) consolidation may be diagnosed if a wedge-shaped opacity of more than a few centimeters in size is visible with the apex of the wedge pointing toward the hilum This finding suggests an abnormality related to a segmental (or subsegmental ) bronchus or artery such as bronchial obstruction due to mucus or tumor, bronchopneumonia , focal aspiration, or pulmonary embolism with infarction.

32. Differential Diagnosis of Consolidation Based on Time Course Rapidly Appearing Consolidation or Consolidation with Acute Symptoms atelectasis with drowned lung, aspiration, pulmonary edema, pulmonary hemorrhage, pulmonary embolism with infarction, or rapidly progressing pneumonia, particularly in an immunocompromised host . Of these, only pulmonary edema and drowned lung may clear quickly.

33. Long-standing Consolidation or Consolidation with Chronic Symptoms Long-standing (chronic) consolidation (4 to 6 weeks or longer) suggests eosinophilic pneumonia, organizing pneumonia mucinous adenocarcinoma lymphoma lipoid pneumonia indolent pneumonias caused by fungal organisms. Recurrent processes (e.g., recurrent pulmonary edema, pulmonary hemorrhage, or aspiration) may appear to be chronic if radiographs are obtained only during the acute episodes.

34. Anatomic relationships and the silhouette sign on a frontal radiograph. Obscuration of the borders shown in this diagram is associated with consolidation of the listed lobes. RUL, right upper lobe; RML, right middle lobe; RLL, right lower lobe; LUL, left upper lobe; LLL, left lower lobe.

35. The silhouette sign in right upper lobe pneumonia. A: Consolidation of the right upper lobe obscures (i.e., silhouettes) the border of the right superior mediastinum and superior vena cava. The upper part of the right hilum is also invisible. B: On the lateral view, the consolidated upper lobe is outlined superiorly by the upper aspect of the major fissure (black arrows). Inferiorly, it is outlined by the minor fissure (white arrows).

36. he silhouette sign in right middle lobe pneumonia. A: Consolidation of the right middle lobe obscures (“silhouettes”) the right heart border (i.e., it is not clearly seen).In contrast, the left heart border is sharply marginated . The right hemidiaphragm appears sharply marginated . The pneumonia is marginated by the minor fissure (arrow). B: On the lateral view, middle lobe consolidation is visible, marginated above by the minor fissure (large arrows); inferiorly, it is marginated by the major fissure (small arrows).

37. The silhouette sign in right lower lobe pneumonia. A: The frontal view shows right lower lobe consolidation with obscuration of the diaphragm. The right heart border (arrows) remains visible as an edge. B: On the lateral view, complete right lower lobe consolidation is visible, outlined anteriorly by the major fissure (white arrows). The right hemidiaphragm (large black arrows) is sharply marginated anterior to the consolidated lobe but is invisible posteriorly. The posterior left heart border and left hemidiaphragm are sharply marginated (small black arrows).

38. A: The left heart border is obscured because of lingular consolidation. The left superior mediastinum remains sharply marginated because the medial portions of the anterior and apical segments of the left upper lobe remain aerated. B: Typical findings of left upper lobe (LUL; and lingular )consolidation: (1) the left superior mediastinum and aortic arch are obscured, (2) the superior left hilum is obscured, (3) the descending aorta remains visible, (4) the left heart border is obscured, and (5) the left hemidiaphragm remains visible.

39. The silhouette sign in left lower lobe pneumonia. A:The left hemidiaphragm is partially obscured by left lower lobe consolidation (arrows). B: On the lateral view, a portion of the left hemidiaphragm (arrow) also is obscured .

40. THANK YOU