Vena caval foramen

Part of the diaphragm

The caval opening of diaphragm is an opening in the central tendon of diaphragm giving passage to the inferior vena cava as well as to some terminal branches of the right phrenic nerve, and some lymphatic vessels en route to middle phrenic and mediastinal lymph nodes. The foramen occurs between the middle leaf and the right leaf of the central tendon of diaphragm, with the fibres of the central tendon uniting vigorously with the adventitia of the inferior vena cava.

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