The internal jugular vein originates at the jugular foramen by the union of the sigmoid and inferior petrosal sinuses and serves as the principal drainage of the skull, brain, superficial face, and parts of the neck. After exiting the skull via the jugular foramen, along with the glossopharyngeal, vagus, and accessory nerves (CNN IX, X, and XI, respectively), the internal jugular vein traverses the neck within the carotid sheath. The internal jugular vein joins with the subclavian vein to form the brachiocephalic vein. Tributaries include the facial, lingual, pharyngeal, and occipital veins, and the superior and middle thyroid veins. The right internal jugular vein lacks valves where as the left has one valve.
Because the right internal jugular vein lacks valves, two pulsations, known as the jugular venous pulse,
are observed due to right atrial contraction and closure of the tricuspid value. The jugular venous pulse assists the physician in assessing the cardiac health of the patient. For example, an elevated jugular venous pulse may suggest right-sided congestive heart failure or stenosis of the tricuspid valve.