Congenital Lobar Emphysema

Two-month old boy with hyperinflation of the left upper lobe, herniation across the midline and relative paucity of vascular markings. There is also mediastinal shift, compression atelectasis of the left lower lobe and flattening of the left hemidiaphragm. Lobectomy was done due to severe dyspnea.
Congenital lobar emphysema is characterized by hyperinflation of a lobe without destruction of alveolar septa. Bronchial obstruction is thought to be the cause of emphysema. Most cases present in first 6 months of life with dyspnea or cyanosis. LUL involved in about 45% of cases, RML in 30%, RUL 20% and two lobes in 5% of cases.
DD: Lucent hemithorax
1. Congenital cystic adenomatoid malformation.
2. Bronchogenic cyst.
3. Diaphragmatic hernia.
4. Pneumothorax.
5. Pulmonary sling (due to compression of the right main stem bronchus or bronchus intermedius).
Reference: Siegel & Coley 2006: Pediatric imaging. Lippincott Williams & Wilkins.
Credit: Dr Ahmed Haroun
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