Mastoid lymph nodes | |
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Superficial lymph glands and lymphatic vessels of head and neck (mastoid lymph nodes are labeled as posterior auricular glands at center left) | |
Lymph nodes at surface:
Facial lymph nodes:
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Details | |
System | Lymphatic system |
Drains from | Scalp |
Drains to | Superior deep cervical glands |
Identifiers | |
Latin | Nodi lymphoidei mastoidei |
Anatomical terminology |
The mastoid lymph nodes (retroauricular lymph nodes or posterior auricular glands) are a small group of lymph nodes, usually two in number, located just beneath the ear, on the mastoid insertion of the sternocleidomastoideus muscle, beneath the posterior auricular muscle.
A lymph node or lymph gland is an ovoid or kidney-shaped organ of the lymphatic system, and of the adaptive immune system, that is widely present throughout the body. They are linked by the lymphatic vessels as a part of the circulatory system. Lymph nodes are major sites of B and T lymphocytes, and other white blood cells. Lymph nodes are important for the proper functioning of the immune system, acting as filters for foreign particles and cancer cells. Lymph nodes do not have a detoxification function, which is primarily dealt with by the liver and kidneys.
The posterior auricular muscle consists of two or three fleshy fasciculi, which arise from the mastoid portion of the temporal bone by short aponeurotic fibers. They are inserted into the lower part of the cranial surface of the concha.
Their mastoid lymph nodes receives lymph from the posterior part of the temporoparietal region, the upper part of the cranial surface of the visible ear and the back of the ear canal. The lymph then passes to the superior deep cervical glands.
The ear is the organ of hearing and, in mammals, balance. In mammals, the ear is usually described as having three parts—the outer ear, the middle ear and the inner ear. The outer ear consists of the pinna and the ear canal. Since the outer ear is the only visible portion of the ear in most animals, the word "ear" often refers to the external part alone. The middle ear includes the tympanic cavity and the three ossicles. The inner ear sits in the bony labyrinth, and contains structures which are key to several senses: the semicircular canals, which enable balance and eye tracking when moving; the utricle and saccule, which enable balance when stationary; and the cochlea, which enables hearing. The ears of vertebrates are placed somewhat symmetrically on either side of the head, an arrangement that aids sound localisation.
The ear canal is a pathway running from the outer ear to the middle ear. The adult human ear canal extends from the pinna to the eardrum and is about 2.5 centimetres (1 in) in length and 0.7 centimetres (0.3 in) in diameter.
The word mastoid comes from the Ancient Greek : μάσταξ (mástax, "mouth, jaws, that with which one chews").
The neck is the part of the body, on many vertebrates, that separates the head from the torso. It contains blood vessels and nerves that supply structures in the head to the body. These in humans include part of the esophagus, the larynx, trachea, and thyroid gland, major blood vessels including the carotid arteries and jugular veins, and the top part of the spinal cord.
The facial nerve is the seventh cranial nerve, or simply CN VII. It emerges from the pons of the brainstem, controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue. The nerves typically travels from the pons through the facial canal in the temporal bone and exits the skull at the stylomastoid foramen. It arises from the brainstem from an area posterior to the cranial nerve VI and anterior to cranial nerve VIII.
The great auricular nerve originates from the cervical plexus, composed of branches of spinal nerves C2 and C3. It provides sensory innervation for the skin over parotid gland and mastoid process, and both surfaces of the outer ear.
The paired submandibular glands are major salivary glands located beneath the floor of the mouth. They each weigh about 15 grams and contribute some 60–67% of unstimulated saliva secretion; on stimulation their contribution decreases in proportion as the parotid secretion rises to 50%.
The occipital artery arises from the external carotid artery opposite the facial artery. Its path is below the posterior belly of digastric to the occipital region. This artery supplies blood to the back of the scalp and sterno-mastoid muscles, and deep muscles in the back and neck.
Anatomists use the term triangles of the neck to describe the divisions created by the major muscles in the region.
The posterior auricular artery is a small artery that arises from the external carotid artery, above the digastric muscle and stylohyoid muscle, opposite the apex of the styloid process.
The mastoid part of the temporal bone is the back part of the temporal bone. Its rough surface gives attachment to various muscles and it has openings for the transmission of blood vessels. From its borders the mastoid part articulates with two other bones.
The deep cervical fascia lies under cover of the platysma, and invests the muscles of the neck; it also forms sheaths for the carotid vessels, and for the structures situated in front of the vertebral column. Its attachment to the hyoid bone prevents the formation of a dewlap.
The posterior auricular nerve arises from the facial nerve close to the stylomastoid foramen and runs upward in front of the mastoid process; here it is joined by a filament from the auricular branch of the vagus and communicates with the posterior branch of the great auricular as well as with the lesser occipital.
The submandibular triangle corresponds to the region of the neck immediately beneath the body of the mandible.
The occipital triangle, the larger division of the posterior triangle, is bounded, in front, by the Sternocleidomastoideus; behind, by the Trapezius; below, by the Omohyoideus.
The popliteal lymph nodes, small in size and some six or seven in number, are embedded in the fat contained in the popliteal fossa, sometimes referred to as the 'knee pit'. One lies immediately beneath the popliteal fascia, near the terminal part of the small saphenous vein, and drains the region from which this vein derives its tributaries, such as superficial regions of the posterolateral aspect of the leg and the plantar aspect of the foot.
A posterior or subscapular group of six or seven glands is placed along the lower margin of the posterior wall of the axilla in the course of the subscapular artery.
The preauricular deep parotid lymph nodes, from one to three in number, lie immediately in front of the tragus.
The following outline is provided as an overview of and topical guide to human anatomy:
The superficial parotid lymph nodes are a group of lymph nodes anterior to the ear.
The auricular branch of posterior auricular artery is a small artery in the head. It branches off the posterior auricular artery and ascends behind the ear, beneath the posterior auricular muscle, and is distributed to the back of the auricula, upon which it ramifies minutely, some branches curving around the margin of the cartilage, others perforating it, to supply the anterior surface. It anastomoses with the parietal and anterior auricular branches of the superficial temporal artery.
Auricular glands can refer to:
This article incorporates text in the public domain from page 693 of the 20th edition of Gray's Anatomy (1918)
The public domain consists of all the creative works to which no exclusive intellectual property rights apply. Those rights may have expired, been forfeited, expressly waived, or may be inapplicable.
Gray's Anatomy is an English language textbook of human anatomy originally written by Henry Gray and illustrated by Henry Vandyke Carter. Earlier editions were called Anatomy: Descriptive and Surgical, Anatomy of the Human Body and Gray's Anatomy: Descriptive and Applied, but the book's name is commonly shortened to, and later editions are titled, Gray's Anatomy. The book is widely regarded as an extremely influential work on the subject, and has continued to be revised and republished from its initial publication in 1858 to the present day. The latest edition of the book, the 41st, was published in September 2015.
Baylor College of Medicine (BCM), located in the Texas Medical Center in Houston, Texas, US, is a health sciences university. It includes a medical school, Baylor College of Medicine; the Graduate School of Biomedical Sciences; the School of Allied Health Sciences; and the National School of Tropical Medicine. The school, located in the middle of the world's largest medical center, is part owner of Baylor St. Luke's Medical Center, part of the CHI St. Luke's Health system, and has hospital affiliations with: Harris Health System, Texas Children's Hospital, The University of Texas MD Anderson Cancer Center, Memorial Hermann – The Institute for Rehabilitation and Research, Menninger Clinic, the Michael E. DeBakey Veterans Affairs Medical Center and Children's Hospital of San Antonio.
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