Findings: After placement of a nasogastric tube, there are multiple air-filled loops of bowel within the left hemithorax (film #1). There is a marked shift of mediastinal structures to the right and the left lung is hypoplastic. A post-surgical film (film #2) demonstrates a well-aerated hypoplastic left lung with a left pneumothorax. Subsequent days later, the patient is extubated (film #3) with even better aeration and expansion of the left lung.

Diagnosis: Congenital Diaphragmatic Hernia-Bochdalek type.

Discussion: Bochdalek hernia is the most common form of diaphragmatic hernia and is the most common surgical emergency of the neonatal period. Bochdalek hernia occurs in 1 in 2500 live births (M:F-2:1). This anomaly is secondary to incomplete closure of the posterior pleuroperitoneal communication of Bochdalek.

Herniated bowel most commonly passes through a posterior diaphragmatic defect on the left side, resulting in pulmonary hypoplasia of the left lung with shift of the mediastinal structures to the right side. Patients with Bochdalek hernias always have malrotation; other associated abnormalities may include neural tube defects and cardiovascular anomalies.

Treatment involves repositioning herniated bowel into the abdomen. Patients are placed on extracorporeal oxygenation (ECMO) to allow for lung regeneration.

References:

1. Blickman H, Pediatric Radiology: The Requisites, 2nd Edition. 1998 p 24.

2. Kirks D. Practical Pediatric Imaging: Diagnostic Radiology of Infants
   and Children, 2nd Edition. 1991:742-744.