Figures
- Figure 1
Posteroanterior chest radiograph showing increased translucency of the left hemithorax with displacement of mediastinal structures to the contralateral side.
- Figure 2
Axial section of the chest CT at the level of the main carina showing shift of mediastinum to right side and hyperinflation of left lower lobe and compression of adjacent parenchyma.
- Figure 3
a and b) Coronal sections of the chest CT showing hyperinflation of left lower lobe with displacement of oblique fissure and compression of adjacent upper lobe. Vascular markings are noted inside the hyperinflated lungs and are attenuated.
Tables
- Table 1
Differential diagnosis of unilateral hyperlucent lung
Anatomical site Radiological and supportive findings Abnormalities 1. Technical issue Hyperlucency on the side to which patient is rotated Rotation 2. Chest wall Normal vasculature of hyperlucent side Poland syndrome (hypoplasia of pectoralis muscle)
Mastectomy3. Pleural spaces Thin sharp pleural line with no vascular markings peripheral to it Pneumothorax 4. Parenchymal defect Obstructive hyperinflation: hyperlucent lung with spreading and narrowing of pulmonary vessels
Characteristic appearance: at full expiration normal lung volume decreases whereas the diseased side volumes remain fairly similar
Compensatory hyperinflation: small or normal sized hyperlucent lung, spreading of the vascular markings and displacement of the ipsilateral hilum with normal decrease in volume of lung in the expiratory filmsCongenital lobar emphysema
Swyer–James–MacLeod syndrome
Unilateral bullous emphysema or cystic lung diseases
Atelectasis/lobectomy5. Vascular defect: congenital Hyperlucent lung, a small hilum, poor vascularisation, and ipsilateral shift of the mediastinum
Normal reduction in lung size on expirationAplasia of a pulmonary artery (its proximal interruption) and pulmonary hypoplasia Vascular defect: acquired Unilateral hyperlucent lung with no evidence of air trapping on both inspiratory and expiratory radiographs
Normal sized lung and the ipsilateral hilum is normal size/ enlargedPulmonary thromboembolism, fibrosing mediastinitis, sequelae of mediastinal irradiation 6. Airway defect Abnormally large affected side even in expiratory film
Obstruction in spirometryUnilateral obstruction: bronchial atresia, extrinsic and intrinsic causes of bronchial compression (such as a foreign body), endobronchial tumours
Vol 16 Issue 4
Table of Contents
An unusual case of unilateral hyperlucent lung
