18 Airspace DiseasesDr. Muhammad Bin ZulfiqarPGR IV FCPS Services Institute of Medical Sciences / Hospitalradiombz@gmail.comGRAINGER & ALLISON’S DIAGNOSTIC RADIOLOGY

• FIGURE 18-1 Chest radiograph in a young male patient with pneumonia. The ■presence of focal consolidation in a patient with pyrexia and a productive cough should prompt a radiological diagnosis of infection as opposed to another cause of airspace opacification.

• FIGURE 18-2 (Non-infective) organising pneumonia. Coronal ■ HRCT image demonstrates areas of consolidation in a subpleural and peribronchial distribution in association with areas of ground-glass opacification in the upper lobes. In the left lower lobe, a ring-shaped focus of consolidation surrounding with a central area of ground glass (the reverse halo or Atoll sign) is shown.

• FIGURE 18-3 (A–C) Rapid changes in radiographic ■appearances in pulmonary oedema. Serial chest radiographs over roughly a 48-h period show striking changes in the extent / severity of airspace opacification, reflecting relatively rapid shifts of fluid between the intravascular compartment and the air spaces/interstitium.

• FIGURE 18-3 (A–C) Rapid changes in radiographic ■appearances in pulmonary oedema. Serial chest radiographs over roughly a 48-h period show striking changes in the extent / severity of airspace opacification, reflecting relatively rapid shifts of fluid between the intravascular compartment and the air spaces/interstitium.

• FIGURE 18-4 Magnified view of a pulmonary lobule on HRCT: ■ under normal conditions, the three basic components of the lobule—the interlobular septa and septal structures (veins), the central lobular region (effectively the centrilobular artery alone), and the lobular parenchyma—can be identified on HRCT. The centrilobular bronchioles and lymphatic vessels are not resolved on HRCT.

• FIGURE 18-5 HRCT appearance of interstitial ■infiltration caused by interstitial oedema. Interlobular septal thickening can be seen in the right lung delineating several secondary pulmonary lobules.

• FIGURE 18-6 Nodular ■airspace opacities on HRCT. Targeted image of the right lung showing numerous ill-defined nodules in a patient with disseminated pulmonary tuberculosis.

• FIGURE 18-7 Ground-glass opacification on CT in an ■immunocompromised patient with Pneumocystis jiroveci infection.

• FIGURE 18-8 Variable causes of ground-glass opacification on ■CT caused by airspace and/or interstitial processes. (A) Diffuse pulmonary haemorrhage in a patient with disseminated cancer. (B) Ground-glass opacification and thickened inter- and intralobular septa in a patient with pulmonary oedema. (C) Ground-glass opacification caused a predominant interstitial lung disease; there are dilated segmental and subsegmental airways (‘traction bronchiectasis’) in areas of ground-glass opacification indicating fine fibrosis.

• FIGURE 18-8 Variable causes of ground-glass opacification on CT ■caused by airspace and/or interstitial processes. (A) Diffuse pulmonary haemorrhage in a patient with disseminated cancer. (B) Ground-glass opacification and thickened inter- and intralobular septa in a patient with pulmonary oedema. (C) Ground-glass opacification caused a predominant interstitial lung disease; there are dilated segmental and subsegmental airways (‘traction bronchiectasis’) in areas of ground-glass opacification indicating fine fibrosis.

• FIGURE 18-9 ‘Black bronchus’ sign on CT. There is ■an almost imperceptible increase in lung density. However, air within the segmental bronchi is clearly of lower attenuation than the surrounding parenchyma.

• FIGURE 18-10 Consolidation on CT in a patient with acute ■respiratory distress syndrome. Compared with areas of ground glass opacification, there is obscuration of bronchovascular markings by areas of dense parenchymal opacification in the dependent lung.

• FIGURE 18-11 Perilobular pattern of cryptogenic ■organising pneumonia in a young female patient. CT through the lung bases shows a striking ‘arcade-like’ distribution of consolidation.

• FIGURE 18-12 Upper lobe blood diversion. ■Vessels in the upper zones are prominent in comparison to those in the lower lung zones.

• FIGURE 18-13 Magnified view of the left costophrenic region ■demonstrating multiple interstitial (Kerley B) lines. Each line is roughly perpendicular to the chest wall and extends to the pleural surface.

• FIGURE 18-14 Asymmetrical distribution of ■airspace opacification in a patient with pulmonary oedema. There is patchy opacification in the right lung with relative sparing of the left.

• FIGURE 18-15 Pulmonary oedema on chest radiography ■demonstrating the characteristic ‘bat’s wing’ distribution with airspace opacification principally within the central lung.

• FIGURE 18-16 (A) ■Pulmonary oedema on CT: there is subtle ground-glass opacification, smooth thickening of multiple interlobular septa and peribronchovascular cuffing. Bilateral pleural effusions are also seen. (B) More conspicuous ground-glass opacification and consolidation as the severity of oedema increases.

• FIGURE 18-17 (A–C) Chest radiographs and (D) HRCT in a patient with idiopathic ■pulmonary haemosiderosis. (A) There is diffuse ground-glass opacification with no zonal predilection during an acute hospital admission with haemoptysis. (B) Radiograph taken 4 days later shows striking (but incomplete) resolution of airspace opacities. There is residual opacification around the right hilum. (C) Chest radiograph obtained 1 month following admission demonstrates ground-glass opacification in the right mid zone. (D) HRCT through the lower zones (concurrent with the radiograph in (A)) shows patchy ground-glass opacification with a somewhat unusual geographical distribution; there are thickened interlobular septa in areas of ground-glass opacification.

• FIGURE 18-17 (A–C) Chest radiographs and (D) HRCT in a patient with idiopathic ■pulmonary haemosiderosis. (A) There is diffuse ground-glass opacification with no zonal predilection during an acute hospital admission with haemoptysis. (B) Radiograph taken 4 days later shows striking (but incomplete) resolution of airspace opacities. There is residual opacification around the right hilum. (C) Chest radiograph obtained 1 month following admission demonstrates ground-glass opacification in the right mid zone. (D) HRCT through the lower zones (concurrent with the radiograph in (A)) shows patchy ground-glass opacification with a somewhat unusual geographical distribution; there are thickened interlobular septa in areas of ground-glass opacification.

• FIGURE 18-18 Wegener’s ■granulomatosis. (A) Multiple intrapulmonary nodules within both lungs on chest radiograph in a patient with elevated c-ANCA titers. (B) CT through the lower zones also demonstrates multiple pulmonary nodules. However, there is clear evidence of cavitation (not seen on the chest radiograph) in one of the lesions in the right lower lobe.

• FIGURE 18-19 HRCT through the lower ■lobes in a patient with biopsy-proven Wegener’s granulomatosis. There is multifocal consolidation and a thick-walled cavity in the left lower lobe.

• FIGURE 18-20 Bronchocentric disease in ■Wegener’s granulomatosis. Many of the segmental and subsegmental bronchi are thick walled (arrows). (Courtesy of Dr Kate Pointon, Nottingham City Hospital, UK.)

• FIGURE 18-21 ■Cryptogenic organising pneumonia in a patient presenting with a cough, breathlessness and weight loss. (A, B) Patchy multifocal consolidation and ground-glass opacities in the mid and lower zones. (C, D) Relapse caused by suboptimal treatment, 6 months later: there is patchy consolidation in the upper zones.

• FIGURE 18-21 ■Cryptogenic organising pneumonia in a patient presenting with a cough, breathlessness and weight loss. (A, B) Patchy multifocal consolidation and ground-glass opacities in the mid and lower zones. (C, D) Relapse caused by suboptimal treatment, 6 months later: there is patchy consolidation in the upper zones.

• FIGURE 18-22 A 37-year-old patient was treated ■with sulfasalazine for Crohn’s disease and one month later developed dyspnoea and fever. HRCT shows right lower lobe consolidation (A, B) and the reversed halo sign (C), suggesting the diagnosis of organising pneumonia.

• FIGURE 18-22 A 37-year-old patient was treated with ■sulfasalazine for Crohn’s disease and one month later developed dyspnoea and fever. HRCT shows right lower lobe consolidation (A, B) and the reversed halo sign (C), suggesting the diagnosis of organising pneumonia.

• FIGURE 18-23 Chronic eosinophilic pneumonia in a male ■patient complaining of a dry cough, weight loss and significant peripheral eosinophilia. HRCT through the upper lobes with bilateral patchy l areas of ground-glass opacification and consolidation in a peripheral distribution.

• FIGURE 18-24 ‘Crazy-paving’ pattern in alveolar ■proteinosis. Patchy but geographical ground-glass opacification is seen and there are numerous thickened interlobular septa in areas of ground-glass opacification.