Space
Aortic hiatus
Posterior route beneath the median arcuate ligament
High-yield
Pair this opening with the aorta and thoracic duct. Its posterior position distinguishes it from the more anterior esophageal and caval passages.
Overview
At roughly T12, the aorta crosses from chest to abdomen between the diaphragmatic crura. It lies behind their connecting median arcuate ligament, rather than within the muscular esophageal opening.
Reference facts
- Boundaries
- Median arcuate ligament in front, diaphragmatic crura at the sides and vertebral column behind, conventionally near T12
- Contents
- Aorta and thoracic duct; an azygos-system vein may also pass through this region
- Communications
- Posterior mediastinum to the upper retroperitoneal region
Clinical correlation
The median arcuate ligament may compress the celiac artery below this region. Compression on imaging can also occur without symptoms, so it alone does not establish median arcuate ligament syndrome.
Frequently asked questions
What are the boundaries of the aortic hiatus?
The aortic hiatus is bounded by the median arcuate ligament in front, diaphragmatic crura at the sides and vertebral column behind, conventionally near T12.
What does the aortic hiatus contain?
Aorta and thoracic duct; an azygos-system vein may also pass through this region.
What does the aortic hiatus communicate with?
Posterior mediastinum to the upper retroperitoneal region.