Space
Caval opening
Passage for the vena cava within tendon
High-yield
This opening has tendinous margins. Contrast it with the muscle surrounding the esophageal hiatus and the posterior route taken by the aorta.
Overview
The inferior vena cava crosses the right side of the diaphragm's central tendon just before reaching the right atrium. T8 is the conventional teaching level for this passage, although its position varies with anatomy and breathing.
Reference facts
- Boundaries
- Right part of the central tendon, usually described at approximately T8
- Contents
- Inferior vena cava and accompanying right phrenic branches
- Communications
- Upper abdomen to the pericardial region immediately below the right atrium
Mnemonic
Keep the caval passage first in the upward-to-downward sequence: cava 8, esophagus 10, aorta 12.
Clinical correlation
Branches of the right phrenic nerve travel close to the caval passage. Surgery around the vena cava and diaphragm therefore requires attention to both venous and diaphragmatic function.
Frequently asked questions
What are the boundaries of the caval opening?
The caval opening is bounded by the right part of the central tendon, usually described at approximately T8.
What does the caval opening contain?
Inferior vena cava and accompanying right phrenic branches.
What does the caval opening communicate with?
The caval opening communicates with the upper abdomen to the pericardial region immediately below the right atrium.