Lecture Notes: Blood Vessels of the Head and Neck

Overview

• Focus on the blood vessels around the head and neck.
• Discuss arteries first, followed by veins.

Arteries of the Head and Neck

Left Common Carotid Artery

• Originates from the aortic arch (second branch after the brachiocephalic artery).
• Ascends superiorly and bifurcates into:
  • External Carotid Artery
  • Internal Carotid Artery

Internal Carotid Artery

• Passes through the carotid canal and foramen lacerum.
• Supplies the Circle of Willis (more detail in separate lecture).

External Carotid Artery

• Supplies external structures.
• Major branches include:
  • Superior Thyroid Artery
  • Lingual Artery: Supplies the tongue.
  • Facial Artery: Supplies facial muscles and skin.
  • Maxillary Artery: Posterior to the mandibular condyle.
  • Superficial Temporal Artery: Supplies the temple region.
  • Occipital Artery: Dips under the mastoid process.

Supra-Troclear Artery

• Emerges from the orbit and runs with the supra-troclear nerve.

Left Subclavian Artery

• Third major vessel from the aortic arch.
• Continues as the axillary artery.

Veins and Dural Sinuses

Dural Sinuses

• Act like veins; enclosed within the dural space.
• Superior Sagittal Sinus: Drains blood via the falx cerebri.
• Occipital Sinus
• Confluence of Sinuses: Junction of several sinuses.
• Transverse Sinus
• Superior Petrosal Sinus
• Inferior Petrosal Sinus: Associated with the abducens nerve.
• Sigmoid Sinus: Drains into the internal jugular vein.

Internal Jugular Vein

• Exits through the jugular foramen.
• Combines with the subclavian vein to form the brachiocephalic vein.

External Jugular Vein

• Drains superficial structures (face, back of the head).

Blood Flow Summary

• Left Internal Jugular Vein: Combines with the left subclavian vein to form the left brachiocephalic vein.
• Right External Jugular Vein: Empties into the right subclavian vein.
• Right Internal Jugular Vein: Combines with right subclavian vein to form the right brachiocephalic vein.
• Both brachiocephalic veins form the superior vena cava, which empties into the right atrium of the heart.

Conclusion

• Covered the structure and flow of blood through the vessels of the head and neck.
• Encouraged engagement and feedback from the audience.