lymph system Flashcards
what does the lymph system consist of
- vessels, nodes, ducts and tonsils
- also the thymus and the spleen
what do the lymphatic vessels do
- they are a system of channels that parallel the venous blood vessels yet are more numerous
what is lymph
- tissue drainage from the surrounding region into the lymphatic vessels
what are lymph nodes and where are they located
- bean shaped bodies grouped in clusters along the connecting lymphatic vessels that filter toxic products from the lymph to prevent their entry into the vascular system
- positioned beside lymphatic vessels. can be deep or superficial
what do lymph nodes contain (tonsils also contain these)
- lymphocytes (the white blood cells of the immune system that actively remove toxins)
- the nodes are also involved in the production of lymphocytes
can we feel/see lymph nodes in healthy patients
- no
how does lymph flow into the lymph nodes
- through afferent vessels (multiple)
how does lymph flow out of lymph nodes
- through efferent vessels (only one per node)
where are the efferent vessels found in lymph nodes
- in a depression called the hilus
what are primary and secondary lymph nodes
- lymph from a particular region first drains into a primary node (regional node or master node). primary nodes, in turn, drain into a secondary node (central node)
what are lymph ducts and where do we find them
- the final drainage point of lymphatic vessels. found in the outer tissue of the body, is where smaller lymphatic vessels containing lymph converge into larger lymphatic ducts
- two lymph ducts, both found in the thorax (chest)
what do we call the lymphatic duct on the right side of the body and what parts of the body does it drain
- called the right lymphatic duct, drains the right arm and right side of the chest
where do the lymphatic ducts on the right side of the body join to drain into the right lymphatic duct
- right side of the head and neck converges by way of the jugular trunk and joins the lymphatic system from right arm and thorax
what do we call the lymphatic duct on the left side of the body and what parts of the body does it drain
- called the thoracic duct, drains the left arm, left side of the chest and the entire lower body
what is lymphadenopathy
- the resultant increase in size and change in consistency of the lymphoid tissue from a patient having cancer or infection in the same region as the affected lymph node
what is lymphadenitis
- in some cases of infection the lymph node can undergo inflammation, which we call lymphadenitis
what is metastasis
- the spread of a cancer from the original or primary site of the neoplasm to another or secondary site (cancer spreading)
what could a painful palpation of a lymph node be a sign of
- a late finding when cancer begins to involve surrounding nerve tissue
what are lymphomas
- malignant neoplasms of component cells of lymphoid tissues
what are the five groups of paired superficial lymph nodes located in the head
1 - occipital 2 - posterior auricular 3 - anterior auricular 4 - superficial parotid 5 - facial
how many occipital lymph nodes are there, where are they located and where do they empty
- about 1-3 in number
- located on the posterior base of the head in the occipital region and drain this part of the scalp
- empty into the inferior deep cervical nodes
how can we examine occipital lymph nodes
- have the patient lean the head forward, allowing for effective bilateral palpation during extraoral examination at the base of each side of the head for these nodes
how many posterior auricular lymph nodes are there and where are they located
- about 1-3 in number
- located posterior to each auricle and external acoustic meatus, where the sternocleidomastoid muscle inserts on the mastoid process
how many anterior auricular lymph nodes are there and where are they located
- about 1-3 in number
- located immediately anterior to each tragus
how many parotid lymph nodes are there and where are they located
- about 10 in number along with the deep parotid group
- located just superficial to each parotid salivary gland
what do the posterior auricular, anterior auricular and superficial parotid lymph nodes all work together to drain
- the external ear, lacrimal gland and adjacent regions of the scalp and face
- all of these nodes eventually empty into the deep cervical node
how do we palpate the posterior auricular, anterior auricular and superficial parotid lymph nodes
- bilaterally palpate these nodes, as well as the face and scalp anterior to and around each auricle
how many facial lymph nodes are there and where are they located
- up to 12 in number and are superficial nodes located along the facial vein with its diagonal course across the side of the face
the facial nodes can be further categorized into four subgroups:
1 - the malar
2 - nasolabial
3 - buccal
4 - mandibular
where are the malar lymph nodes located
- the infraorbital region (can also be called the infraorbital nodes)
where are the nasolabial lymph nodes located
- along the nasolabial sulcus
where are the buccal lymph nodes located
- around the labial commissure and just superficial to the buccinator muscle
where are the mandibular lymph nodes located
- in the tissue superior to the surface of the mandible and anterior to the masseter muscle
how can we palpate facial lymph nodes
- bilaterally palpate these nodes on each side of the face, moving from the infraorbital region to the labial commissure and then to the surface of the mandible
can we palpate the deep lymph nodes in the head region
- no, but these lymph nodes can communicate with the more superficial regional nodes
what are the deep lymph nodes in the head region and where do they drain
- deep parotid and retropharyngeal lymph nodes
- drain into the deep cervical nodes
how many deep parotid lymph nodes are there and where are they located
- up to 10 in number along with the superficial parotid nodes
- located deep within the parotid salivary gland
what do the deep parotid nodes drain
- the middle ear, auditory tube and parotid salivary gland
how many retropharyngeal lymph nodes are there and where are they located
- up to 3 in number
- located near the deep parotid nodes and at the level of the atlas, which is the first cervical vertebra
what do the retropharyngeal nodes drain
- the palate, pharynx, paranasal sinuses and nasal cavity
what are the 4 groups of superficial cervical lymph nodes
1 - the submental
2 - submandibular
3 - external jugular
4 - anterior jugular
how many submental lymph nodes are there and where are they located
- about 2-3 in number
- located inferior to the chin within the submental fascial space as well as the submental triangle, which is between the anterior bellies of the digastric muscles. at this location, these nodes are near the midline inferior to the mandibular symphysis in the suprahyoid region, and also just superficial to the mylohyoid muscle
how many submandibular lymph nodes are there and where are they located
- about 3-6 in number
- located at the inferior border of the mandibular ramus, just superficial to the submandibular salivary gland and within the submandibular fascial space. they are also posterolateral to the anterior belly of the digastric muscles
what nodes are the primary nodes for most of the teeth and associated tissues
- the submandibular nodes
what are the only teeth that don’t drain primarily into the submandibular nodes and which nodes are the primary for these exceptions
- the maxillary third molars (superior deep cervical nodes)
- the mandibular incisors (submental nodes)
where do the submandibular nodes eventually drain into
- the superior deep cervical nodes
where do the superior deep cervical nodes empty into
- either the inferior deep cervical nodes or directly into the jugular trunk, and then into the vascular system
what happens if there is an infection in the submandibular nodes
- since they eventually empty lymph into the vascular system, if the infection goes unnoticed, the infection will end up in the bloodstream and can spread to other tissues, structures and organs
how can we palpate the submental and submandibular nodes
- have the patient lower the chin and manually palpate them directly inferior to the chin
- then, for the more laterally placed submandibular nodes, push the tissue in the area over the bony inferior border of the mandible on each side, where it is grasped and rolled
how many external jugular lymph nodes are there and where are they located
- about 1-2 in number
- located on each side of the neck along the external jugular vein, superficial to the sternocleidomastoid
where are the anterior jugular lymph nodes located
- located on each side of the neck along the length of the anterior jugular vein, anterior to the larynx, trachea and sternocleidomastoid, as well as between the superficial layer of deep cervical fascia and the infrahyoid muscles
how do we palpate the external and anterior jugular nodes in the middle of the neck
- have the patient turn the head to the contralateral side, which makes the important landmark the sternocleidomastoid muscle more prominent. palpate these nodes superficially on each side of the muscle by starting at the angle of the mandible and continue the whole length of the surface of the sternocleidomastoid muscle to the clavicle
how many deep cervical lymph nodes are there and where are they located
- about 15-30 in number
- located along the length of the internal jugular vein on each side of the neck, deep to the sternocleidomastoid
- they extend from the base of the skull to the root of the neck, adjacent to the pharynx, esophagus and trachea
how do we divide the deep cervical nodes and what two groups can they be divided into
- divided based on the vertical anatomic position of the nodes relative to the point where omohyoid muscle crosses the internal jugular vein
1 - the superior deep cervical lymph nodes
2 - the inferior deep cervical lymph nodes
where are the superior deep cervical lymph nodes located
- located deep beneath the sternocleidomastoid muscle, superior relative to where the omohyoid crosses the internal jugular vein
what is the jugulodigastric lymph node or tonsillar node and where is it located
- one of the superior deep cervical nodes
- becomes noticeable palpable when the palatine tonsils undergo nodal enlargement or lymphadenopathy
- the jugulodigastric node is located inferior to the posterior belly of the digastric muscle and posterior to the mandible
where do the superior deep cervical nodes drain
- primary drainage for the posterior nasal cavity, posterior hard palate, soft palate, base of the tongue, maxillary third molars with associated periodontium gingiva, temporomandibular joint, esophagus, trachea and thyroid gland
- important to note that since lymphatic drainage of the base of the tongue is bilateral in the posterior region, the contralateral node may also be affected if pathology is occurring there
what s the jugulo-omohyoid lymph node and where is it located
- prominent node of the inferior deep cervical nodes
- located at the actual crossing of the omohyoid muscle and the internal jugular vein
how do we palpate the deep cervical lymph nodes
- have the patient turn the head to the contralateral side, which makes the most important landmark of the sternocleidomastoid muscle more prominent and increases accessibility for effective palpation of these nodes
- palpation of the deep cervical nodes is performed on the underside of both the anterior and posterior aspects of the scm muscle in contrast to the superficial cervical nodes that are on the muscles surface
- using bidigital palpation, start at the angle of the mandible and continue down the length of the scm muscle to the clavicle
what do calcified nodes often mean
- past rather than active infections
what are the axillary lymph nodes and where do they drain
- inferior deep cervical nodes also communicate with the axillary lymph nodes that drain the breast region
- this is due to nodal communication, the inferior deep cervical nodes are at great risk for involving the spread of breast cancer of adenocarcinoma
what are the 2 additional node groups in the inferior part of the neck
- the accessory nodes
- the supraclavicular nodes
how many accessory lymph nodes are there and where are they located
- about 2-6 in number
- located along the 11th cranial or accessory nerve
what do the accessory lymph nodes drain
- the scalp and neck regions and then drain into the supraclavicular nodes
how many supraclavicular lymph nodes are there and where are they located
- about 1-10 in number
- located along the clavicle close to where the sternum joins it
why are the supraclavicular nodes so important in the spread of cancers
- these nodes are located in the final endpoint of lymphatic drainage from the entire body
- because of this location, these nodes are at great risk for involving the spread of cancers arising from the lungs, esophagus and stomach
- therefore, inspection of these nodes is important in any comprehensive patient assessment
how can we palpate the interior deep cervical, accessory, and supraclavical lymph nodes
- for those nodes near the clavicle, have the patient raise the shoulders up and forward, allowing for effective palpation during an extraoral exam using the trapezius muscle as a base
where do the tonsils drain into
- the superior deep cervical lymph nodes, particularly affecting the jugulodigastric lymph node if there is an infection in the region (considered the tonsillar node)
4 types of tonsils
1 - palatine tonsils: what patients call their tonsils, located between the anterior and posterior faucial pillars
2 - lingual tonsils: located on the dorsal surface of the base of the tongue
3 - pharyngeal tonsils: located on the midline of the posterior wall or roof of the nasopharynx, also called the adenoids
4 - tubal tonsil: also located in the nasopharynx, posterior to the openings of the eustachian or auditory tube
how can we visually observe the palatine tonsils
- gently place the mouth mirror with the mirror side down on the middle of the tongue and ask the patient to say ah