 It is continued behind the depressor muscles of the hyoid bone, and, after enveloping the thyroid gland, is prolonged in front of the trachea to meet the corresponding layer of the opposite side.The pretracheal layer of the deep cervical fascia passes in front of the carotid sheath (i.e., common carotid artery, internal jugular vein and vagus) and in front of the cervical viscera (larynx, oesophagus and pharynx).Above, it is fixed to the hyoid bone, while below it is carried downward in front of the trachea and large vessels at the root of the neck, and ultimately blends with the fibrous pericardium.