An interesting chest radiographBMJ 2008; 337 doi: https://doi.org/10.1136/bmj.a1505 (Published 24 September 2008) Cite this as: BMJ 2008;337:a1505
- Sylvia A O’Keeffe, specialist registrar,
- Andrew McGrath, specialist registrar,
- Graham Wilson, consultant radiologist
- 1Department of Radiology, St James’s Hospital, Dublin 8, Ireland
- Correspondence to: S A O’Keeffe
A 63 year old man presented with a two week history of shortness of breath, fatigue, and cough. He had a 20 pack year ((number of cigarettes smoked each day times number of years smoked)/20) smoking history and no appreciable occupational exposure to dusts such as asbestos or coal. On examination his trachea was slightly deviated to the left with slightly diminished breath sounds over the left lung.
1. What does the figure⇓ show?
2. What is the luftsichel (air sickle) sign?
3. What disease processes can cause this finding?
4. What further investigations are needed?
1. Posteroanterior and lateral chest radiographs show complete collapse of the left upper lobe.
2. In left upper lobe collapse, hyperinflation of the superior segment of the left lower lobe occurs. This aerated segment is lucent and shaped like a sickle; it outlines the aortic knob on the posteroanterior radiograph (indicated by the arrowhead in the left hand panel of the figure).1
3. Bronchogenic carcinoma (either endobronchial or causing extrinsic compression), lymphadenopathy, mucous plugging (as a result of asthma, cystic fibrosis, patient being in intensive care), foreign body aspiration, iatrogenic causes (such as misplaced endotracheal tube), and rare tumours such as endobronchial carcinoid.
4. Bronchoscopy, computed tomography (thorax, liver, and adrenals), and positron emission tomography if needed.
The posteroanterior radiograph and lateral chest radiograph show complete collapse of the left upper lobe (fig 1). This is seen on the posteroanterior radiograph as a veil-like increased density projected over the left hemithorax with associated elevation of the left hemidiaphragm and loss of definition of the left side of the mediastinum (fig 1a; arrow).2 On the lateral view the collapsed upper lobe is clearly demarcated from the lucent lower lobe by the …