FORAMEN OF MORGAGNI HERNIA

Foramen of Morgagni hernias occurs in the anteromedial retrosternal portion of the diaphragm due to maldevelopment of the septum transversum. These hernias often lack a hernia sac composed of abdominal peritoneal layers.

Depending of the integrity of the pericardium, abdominal contents may herniate into the pericardial space.

ULTRASOUND

• Anteromedial diaphragmatic defect.
• Stomach may remain below the diaphragm.
• May allow bowel or liver to herniate into the anterior mediastinum.
• Ascites, pleural or pericardial effusion may outline the herniated viscera, as these hernias often lack a peritoneal covering.

ASSOCIATED ANOMALIES

• Occur in >50% of infants (1)
• Malrotation is the most common associated gastrointestinal tract abnormality.
• Chromosomal defects (trisomy in 4 %) (1).
• Cardiovascular defects.

REFERENCES

1. Adzick NS, Harrison MR, Glick PL et.al. Diaphragmatic hernia in the fetus: Prenatal diagnosis and outcome in 94 cases. J Pediatr Surg 1985;20:357-361.