Expansion
Inferior vena cava and the right phrenic nerve
Expansion
At the level of T8, through the central tendon:
- Inferior vena cava
- Right phrenic nerve
- A few lymphatic vessels
Because the opening lies in the tendinous part of the diaphragm, its margins are pulled apart on inspiration. This widens the caval opening and helps venous return, the opposite of what happens at the oesophageal hiatus, where muscular contraction pinches the oesophagus shut.