WEEK 3 - LYMPHATICS Flashcards
list the course of the lymphatic system
lymphatic capillaries > lymphatic vessel > lymphatic node > lymphatic duct > veins in root of neck
function of heart
pumps blood > blood flows within vessels (arteries, capillaries and veins)
function of capillaries
- exchange of fluids, nutrients and waste with interstitial spaces. not all fluids from capillaries returns to veins > rest taken up by lymphatic system
lymphatic capillaries functions
- blind-ended structure, mop up:
1: excess fluid in interstital space
2: cellular debris and pathogens
3: leaked plasma proteins
function of lymph vessels
- not driven by a pump
flow towrds venous system aided by compression, supported by numerous valvesw
where do lymph vessels drain into
- lymph nodes
where do lymphatic vessels drain into
veins
list the THREE main functions of lymph vessels
- collection of tissue fluid and return to systemic circulation
- transport of lymphocytes and other immune cells
- transport of long chain fatty acids from the small inestine via lacteals in villi of intestines
where do lymphs mostly empties into
venous system at the jugulosubclavian junctions
what do lymph capillaries arise as
permeable, blindly ending tubes in CT and drain into larger lymph vessels
are lymph vessels always small or large
small
eg: thoracic duct is only few mm in diameter
what do vast majority of larger lymph vessels contain
valves
list the TWO main functions of lymph nodes
- immunosurveillance of lymph
- production of lymphocytes and other immune cells which are taken up by lymph
where are lymph nodes found mostly
- head
- neck
- trunk
- few in limbs
what are lymph nodes ALWAYS associated with
lymph vessels
what do most medium to large lymph vessels pass through
at least one node
but some exceptions: thoracic duct does not have associated nodes
list the other lymph organs
- spleen
- thymus
- tonsils
list the TWO lymph drainage ducts of the body
- thoracic duct > drains L. upper limb. L. head and neck, L. thorax and lower half of body
- right lymphatic duct > R. upper limb, R. head and neck, R. thorax
where does the thoracic duct beings in
abdomen at the level of L2 as CISTERNA CHYLI
where does thoracic duct receives tributaries from
- gut > via intestinal trunk
- lower limbs
- lower thorax
where does the thoracic duct receives lymph from three tribuatries before draining into the venous circulation
- bronchomediastinal lymph trunk
- subclavian lymph trunk
- jugular lumph trunk
where are the valves in major lymph trunks
- numerous along the length of thoracic duct and right lymphatic duct (if present)
where are valves also located
- at the terminations of the subclavian and bronchomediastinal trunks into the thoracic duct or right lymphatic duct
what are lymph nodes of the head and neck divided inot
superficial and deep
where do superficial nodes of the neck drains into
deep nodes –> drain into the jugular lymph trunk
list the SUPERFICIAL nodes of the head
- occipital
- retroauricular/mastoid
- parotid
- buccal
superficial lymph nodes of the neck
- superficial cervical (lateral surface of SCM)
- submandibular
- submental (overlie mylohyoid muscle)
- anterior cervical - OVER thyroid, larynx and trachea
what are the deep lymph nodes of the neck further divided into
- superior/upper
- inferior/lower
by the omohyoid muscle
what does the superior/upper deep lymph nodes of the. neck include
- jugulodigastric group
- retropharyngeal group
what does the inferior/lower deep lymph nodes of the neck includes
- jugulo-omohyoid group
- supraclavicular/anterior scalene. muscles
what is the VIRCHOW’ node
lowest of the deep cervical group of nodes
what does the virchow’s node contain
- group of 3-6 nodes located in the left supraclavicular fossa > lateral to clavicular head of SCM and closest to jugular trunk
where does the jugular trunk drains into in virchows node
- thoracic duct that in turn receives lymph from most of the body
what is the retrograde backflow at the venous termination of the thoracic duct prevented by
- a valve located at the subclavian and bronchomediastinal trunks
what does an enlarged virchows node indicate
malignancy in any part of the body
list the three types of tonsils
- pharyngeal (single)
- lingual (single group)
- palatine (paired)
where is pharyngeal tonsil located
beneath mucosa in the posterior wall of pharynx
where is pharyngeal tonsil prominent in children
around opening of auditory tube
what are enlarged pharyngeal tonsils called
adenoids
what are lingual tonsils a collection of
lymph nodules in posterior or pharyngeal part of tongue
where are palatine tonsils located
lateral sides of orophrynx just behind oral cavity within tonsillar fossae