67. Carotid triangle.

CAROTED TRIANGLE

The carotid triangle is a paired space situated ventral to the sternocleidomastoid. The branches of the external carotid artery and structures inside the carotid sheath (common carotid artery, internal jugular vein, vagus nerve and superior root of deep ansa cervicalis) are located in this region. This space continues cranially to the parapharyngeal space and caudally to the scalenovertebral triangle.

Boundaries

1. Cranially: digastric – posterior belly
2. Laterally: sternocleidomastoid
3. Caudally: omohyoid – superior belly

Content

Inside the carotid sheath

1. 1 Common carotid artery – situated medially

• continues as the internal carotid artery from the C4 level upward

2. Internal jugular vein – situated laterally
3. Superior root of deep ansa cervicalis – situated ventrally
4. Vagus nerve – situated dorsally

Outside the carotid sheath

1. 5 External carotid artery
2. 5.1 Superior thyroid artery

• the first branch
• runs caudally to the omotracheal triangle

1. 5.2 Lingual artery

• the second branch
• runs cranially to the submandibular triangle

1. 5.3 Facial artery

• the third branch
• runs cranially to the submandibular triangle

6. Veins – facial vein, retromandibular vein, lingual vein, superior thyroid vein
7. Arch of hypoglossal nerve (arcus nervi hypoglossi)
8. Sympathetic trunk and superior cervical ganglion
9. Accessory nerve
10. Lateral group of the deep cervical lymph nodes