carotid sheath

                                  Dr vivek rao

                                  

2. Carotid sheath The carotid sheath is an anatomical term for the fibrous connective tissue that surrounds the vascular compartment of the neck. It is part of the deep cervical fascia of the neck, The deep cervical fascia of the neck includes four parts:

 1) The investing layer

 2)The carotid sheath (encloses the vascular region of the neck) .

 3) The pre-tracheal fascia (encloses the visceral region of the neck) 

 4) The pre-vertebral fascia (encloses the vertebral region of the neck)

3. CAROTID SHEATH… Carotid Sheath is Formed by all three layers of deep fascia Contains carotid artery, internal jugular vein, and vagus nerve 

4. STRUCTURE OF THE CAROTID SHEATH The four major structures    contained in the carotid sheath are: 

           a)the common carotid artery as well as the internal carotid artery 

           b)Internal jugular vein.

           c) The Vagus nerve (CN X) .

           d)The deep cervical lymph nodes 

              The carotid artery lies medial to the internal jugular vein, and the     vagus nerve is situated posterior between the two vessels. 

          e)In the upper part, the carotid sheath also contains the gloss pharyngeal nerve (IX), the accessory nerve (XI), and the hypoglossal nerve (XII), which pierce the fascia of the carotid sheath.

5. Fascial Layers and Relations 

         The deep cervical fascia of the neck has four layers, listed from superficial to deep. 

        The first is known as the investing layer and surrounds the sternocleidomastoid muscle and the trapezius muscle. 

         The second that of the current topic, the carotid sheath which encompasses the vascular region of the neck. The third is called the pre-tracheal fascia and encloses the visceral region of the neck. Lastly, the fourth fascial layer is the pre-vertebral fascia and it surrounds the vertebral region of the neck. 

          The carotid sheath itself is an accumulation of three of the layers of the deep cervical fascia. These layers include the investing fascia, the pre-tracheal fascia and the pre-vertebral fascia. An important adjacent anatomical structure which can be seen just behind the carotid sheath is the cervical part of the sympathetic trunk which is embedded in the pre-vertebral fascia.