Antrochoanal polyps arise from the maxillary sinuses and are the much less common; ethmoidal polyps arise from the ethmoidal sinuses. Symptoms of polyps include nasal congestion, sinusitis, anosmia (loss of smell), and secondary infection leading to headache.
Relationship of internal jugular vein to the spinal accessory nerve (SAN). Spinal accessory nerve (SAN) posterior to the internal jugular vein. As the nerve approaches the sternocleidomastoid muscle (SCM), it may perforate the cleidomastoid portion of the SCM (80%) or run posterior to it (20%).
The motor branch directed to the deep muscles of the neck and the muscles beneath it the hyoid bone, as well as innervate the sternocleidomastoid and trapezius muscles. Mixed branch of cervical plexus is the phrenic nerve (n. phrenicus). Motor fibers are sent to the phrenic nerve to the diaphragm, and sensitive innervate the pleura and pericardium. Brachial plexus (plexus brachialis) formed branches of the lower four cervical nerves and the anterior branch of the 1st thoracic nerve.