LYMPHATIC SYSTEM consists of: 1. lymph capillaries 2. collecting ...

LYMPHATIC SYSTEM
consists of:
1. lymph capillaries
2. collecting vessels
3. lymph nodes
4. lymphatic organs resembling lymph nodes (tonsills, lymph nodules)
5. spleen
6. thymus
Lymph vessels collect the lymph to the large blood streams (brachiocephalic veins)
Lymph nodes - act as filters for lymph and phagocytes
- are sources of lymphocytes
LYMPH DRAINAGE OF THE UPPER LIMB AND ADJOINING PART OF TRUNK
LYMPH VESSELS OF THE UPPER LIMB
drain lymph into the axillary lymph nodes
are divided into the superficial and deep lymph vessels
1. SUPERFICIAL LYMPH VESSELS
begin in digital plexusses and accompany superficial veins
lateral group of lymph vessels – ascends along cephalic v.
medial group of lymph vessels – accompanies basilic v.
anterior group – ascends in the middle of forearm
2. DEEP LYMPH VESSELS
accompany brachial a. and all its branches
AXILLARY LYMPH NODES
SUPERFICIAL – receive lymph from the superficial vessels
are drained into the deep axillary lymph nodes
DEEP – receive lymph from the supefricial axillary lymph nodes and from deep lymph
vessels
are subdivided into 5 groups
1. brachial (lateral) group
receives lymph from the free upper limb drained by deep and superficial lymph vessels
2. pectoral (anterior) group – is placed near inf. margin of pectoralis minor m.
receiving lymph vessels from the supraumbilical part of trunk – anterior and lateral surfaces
including mammary gland
3. subscapular (posterior) group – is located along the subscapular vessels
drains lymph • from the inferior surface of the back of neck
• from dorsal side of trunk up to the iliac crest
4. central group – lies along the upper margin of pectoralis minor m.
receives the lymph from the preceding three groups
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5. apical group (infraclavicular) – surrounds subclavian a.
receives lymph vessels arising from the central nodes
efferent vessels arising from apical axillary lymph nodes join to form subclavian trunk
Right subclavian trunk – opens into the right brachiocephalic v. (angulus venosus)
Left subclavian trunk – terminates into the thoracic duct which opens into the left
brachiocephalic v. (angulus venosus)
LYMPH DRAINAGE OF LOWER LIMB AND ADJOINING PART OF TRUNK
the lymph from the lower limb and lower part of trunk is drained into the inguinal lymph
nodes
INGUINAL LYMPH NODES
are divided into the superficial and deep groups
SUPERFICIAL INGUINAL LYMPH NODES
Receive lymph from:
•free lower limb – superficial structures (skin, subcutaneous tissue)
•gluteal region
• lateral abdominal wall
• anterior abdominal wall
• external genital organas
• uterus!
• lower part of the anal canal
The lymph from the superficial lymph nodes is drained into the external iliac lymph nodes
and into the deep inguinal lymph nodes
DEEP INGUINAL LYMPH NODES
are placed around femoral vessels in the femoral triangle near the inguinal ligament
receive • deep lymph vessels of lower limb (accompanying blood vessels)
efferent lymph vessels arising from the deep lymph nodes terminate in the external iliac
lymph nodes
LYMPH VESSELS OF FREE LOWER LIMB
Deep – accompany femoral a. and its branches
popliteal lymph nodes are placed around popliteal a.
Superficial lymph vessels – accompany saphenous veins
medial group – ascends along the great saphenous v. (to terminate into the inferior
superficial inguinal nodes)
lateral group – ascends along m the small saphenous v. (to terminate partly into the
popliteal, partly into the inferior superficial inguinal nodes)
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LYMPH ORGANS
THYMUS
lymphoid organ and endocrine gland
main function:
- differentiation of lymphocytes into the different classes
- production of various factors and hormones which regulate lymphocytes production,
differentiation and activities within the thymus, peripheral lymphoid tissue and
elsewhere
located in the anterior mediastinum
extends into the neck
may reach lower part of thyroid gland (in children)
relations:
anteriorly – sternum and costal cartilages
- infrahyoid muscles
posteriorly – heart in pericardium
- brachicephalic veins and sup. v. cava
- aortic arch and its branches
- trachea
laterally – pleurae and lungs
varies in size with age
at birth: 10 – 15 gm
grows up to the puberty: 30 – 40 gm
progressively diminishes – atrophy, replacement by fat
mid-adult life: 10 gm
childhood
pinkish-grey in colour
lobulated
right and left lobes connected by fibroareolar tissue
Structure:
fibrous capsule
septa → lobules
lobule – cortex, medulla (fewer lymphocytes than the cortex)
Blood supply:
arteries
Thymic branches of inf. thyroid a. and int. thoracic a.
Veins – drained into the inf. thyroid, brachiocephalic and
int. thoracic veins
Nerve supply: sympathetic nerves – cervicothoracic ganglion
parasympathetic fibres (vagus n.)
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SPLEEN
- placed in the left hypochondriac region
between the gastric fundus and diaphragm
- long axis lies in the plane of the 10th rib
- posterior extremity lies 4 cm far from the median plane
- anterior extremity reaches mid-axillay line
- it is soft, friable in consistence, dark red in colour
- irregularly ovoid – 12 cm long, 7 cm wide, 3-4 cm thick
- has diaphragmatic and visceral surfaces
superior and inferior margins
anterior and posterior extremities
relations:
diaphragmatic surface – diaphragm which separates it from
- pleural cavity - costodiaphragmatic recess
visceral surface – stomach (gastric impression)
- L kedney (renal impression)
- pancreas (pancreatic impresiion)
- left colic flexure (colic impression )
hilum – splenic a. and v. enter the spleen
spleen – intraperitoneal organ
(develops in the posterior mezogastrium)
gastrosplenic and lienorenal ligaments
accessory spleens – in the gastrosplenic lig. and greater omentum
function:
phagocytosis
immune responses due to lymphocytes
cytopoiesis (haemopoiesis and lymphopoiesis)
storage place of blood
Blood supply: splenic a. (coeliac a.)
splenic v. (portal v.)
Nerve supply: abdominal autonomic plexus
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THE LYMPH VESSELS AND LYMPH NODES OF THE HEAD, NECK AND TRUNK
THE LYMPHATIC DRAINAGE OF THE HEAD AND NECK
Lymph drainage of the superficial tissues of the head and neck
Most lymph vessels accompany branches of external carotid artery
Terminate in small groups of lymph nodes
•Occipital nodes (occipital vessels)
• Retroauricular (posterior auricular vessels)
• Parotid ( temporal superficial vessels)
• Buccal (facial vessels)
• Submandibular (facial vessels in digastric triangle)
Receives afferents from parotid and buccal nodes
and lymph from the oral cavity, tonsils, tongue, teeth)
• Anterior cervical (along the anterior jugular vein)
• Superficial cervical (along the external jugular vein)
nodes represent outlying nodes of deep cervical lymph nodes
the lymph is drained into the deep cervical lymph nodes
Lymph drainage of deep tissues of the head and neck
Directs to the deep cervical lymph nodes
Outlying grops of nodes:
Retropharyngeal – receive lymph from nasopharynx, nasal cavity, auditory tube
Paratracheal nodes – (around trachea and oesophagus) receive the lymph from the larynx,
trachea, oesophagus
the deep cervical lymph nodes
are regional lymph nodes of the head and neck
receive lymph from the superficial and deep structures of the head and neck
lie along the carotid sheath (internal jugular vein, carotid arteries)
subdivided into the superior and inferior group
■ Superior deep cervical lymph nodes
Lie close to the upper part of the internal jugular vein
this group contains jugulodigastric node - near the tendon of digastricus m.- associated
with lymph drainage of the tongue
efferents terminate into the inferior deep cervical lymph nodes
■ inferior deep cervical lymph nodes
around lower part of the internal jugular vein
contain juguloomohyoid node (near the tendon of omohyoid m.)
efferents unite to form
jugular trunk
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THE THORACIC DUCT
main lymph vessel conveying the lymph to the blood stream
arises in the abdomen (at the level of the 12th thoracic vertebra)
by union of right and left lumbar trunks and intestinal trunk – here dilated – cisterna chyli
here it receives the lymph from
• abdominal walls and organs
• pelvic walls and organs
• lower limbs
traverses the diaphragm through the aortic hiatus
ascends in the posterior mediastinum - behind the oesophagus on right side of aorta
turns to the left behind aortic arch and subclavian a.
leaves the thorax (3 – 4 cm above the clavicle)
arches above the subclavian a.
opens into the left brachiocephalic v. (angulus venosus)
here it receives the tributaries
• left subclavian trunk (left upper limb )
• left jugular trunk ( left half of head and neck )
• left bronchopulmonary trunk (left half of the thorax – the walls and organs)
In conclusion:
Thoracic duct drains the lymph from the lower limbs, pelvis (walls, organs), abdomen walls,
organs), left half of the thorax (walls, organs), left upper limb, left half of the neck and head
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lymph from the right half of head and neck, right upper limb and right half of the thorax is
drained into the right lymphatic trunk – terminates into the right angulus venosus
right lymphatic trunk arises by union of right jugular, right subclavian and right
bronchomediastinal trunks
LYMPH DRAINAGE OF THE THORAX
superficial tissues - skin, mammary gland, muscles connecting upper limb to the thorax-
are drained to the axillary lymph nodes (see over there)
deep structures – thoracic walls - ribs, intercostal muscles, diaphragm
and thoracic organs are drained into
the deep lymph nodes of the thorax
lymph drainage of the thoracic walls
parasternal, intercostal, diaphragmatic lymph nodes
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■ parasternal lymph nodes
on sides of internal thoracic vessels
receive lymph from
• anterior thoracic and abdominal wall
• mammary gland
• liver (upper surface)
efferents terminate in the bronchomediastinal trunk
■ intercostal lymph nodes
located near the necks of ribs
receive lymph from
• the posterolateral thoracic wall (ribs, intercostal muscles)
efferents open into the thoracic duct and right lymphatic trunk
■ diaphragmatic lymph nodes
lie around the periphery of the diaphragm
receive lymph from
• diaphragm
• superior surface of the liver
efferents pass into the parasternal nodes, anterior mediastinal and posterior mediastinal
lymph nodes
lymph drainage of the thoracic organs
anterior mediastinal , posterior mediastinal and tracheobronchial lymph nodes
efferents empty into the thoracic duct and right lymphatic duct
■ anterior mediastinal lymph nodes (brachiocephalic l. n.)
are placed in front of the brachicephalic veins and branches of aortic arch
receive lymph from the anterior mediastinum
• thymus
• thyroid gland
• pericardium
• diaphragmatic lymph nodes
efferents terminate in the thoracic duct (and tracheobronchial lymph nodes)
■ tracheobronchial lymph nodes
located near the trachea and tracheal bifurcation
subdivided into
the paratracheal – on sides of trachea
superior tracheobronchial - above bifurcation
inferior tracheobronchial – below the bifurcation
outlying lymph nodes - bronchopulmonary – in the pulmonary hilum
- pulmonary – in the lung substance
receive lymph from
• lungs and bronchi
• trachea
• heart
efferent vessels unite to form bronchomediastinal trunks
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■ posterior mediastinal lymph nodes
around oesophagus and thoracic aorta
drain lymph from
• oesophagus
• heart
• diaphragm
• liver
efferents terminate into the thoracic duct
THE LYMPHATIC DRAINAGE OF THE ABDOMEN
the lymph from the abdominal walls and abdominal organs is drained into
the lumbar and pre-aortic nodes
■ lumbar lymph nodes (lateral aortic)
lie on sides of the abdominal aorta and inf. vena cava
receive lymph from
• the abdominal walls
• suprerenal glands
• kidneys, ureters
• gonads
efferents unite to form lumbar trunk – right and left
outlying lymph nodes in the pelvis - common iliac)- drain
• pelvic walls and pelvic organs
• lower limbs
■ pre-aortic nodes – coeliac, superior mesenteric, inferior mesenteric
receive lymph from the alimentary canal, liver, pancreas, spleen
efferents form intestinal trunk
coeliac lymph nodes
near origin of coeliac artery
receive lymph from the organs supplied by coeliac a. (liver, gall bladder, stomach, duodenum,
pancreas, spleen)
outlying nodes:
hepatic - along common and proper hepatic a.
gastric – near lesser and greater curvatures and around the pylorus
pancreaticosplenic – along splenic a.
superior and inferior mesenteric lymph nodes
lie close to the origin of sup. and inf. mesenteric arteries
receive lymph from the small and large intestines
outlying nodes:
lymph nodes of the mesentery – drain small intestine
ileocolic nodes – terminal part of ileum, appendix
nodes of the colon – large intestine
superior rectal nodes – upper part of rectum
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THE LYMPHATIC DRAINAGE OF THE PELVIS
■ common iliac lymph nodes
along common iliac vessels
receive lymph from the external and internal iliac lymph nodes
■ external iliac lymph nodes
along external iliac vessels
receive lymph from:
• inguinal lymph nodes
• infraumbilical part of anterior abdominal wall
• adductor region (along obturator vessels)
• penis
• prostate
• urinary bladder, urethra
• uterus, vagina
efferents pass to the common iliac nodes
■ internal iliac lymph nodes
lie along internal iliac vessels
receive lymph from:
• pelvic organs
• perineum (along the internal pudendal vessels)
• muscles of gluteal region (along the gluteal vessels)
efferents pass to the common iliac nodes
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IN SUM
lower limbs (and adjoing part of trunk)
regional lymph nodes – inginal
efferents → external iliac → common iliac → lumbar → lumbar trunk → thoracic duct
pelvis:
regional lymph nodes – internal iliac lymph nodes
efferents → common iliac nodes→ lumbar nodes → lumbar trunk → thoracic duct
abdomen:
regional lymph nodes
- lumbar nodes →lumbar trunk → thoracic duct
- coeliac, superior and inferior mesenteric → intestinal trunk → thoracic duct
thorax:
regional lymph nodes
- parasternal, intercostal, diaphragmatic (for the walls) → thoracic duct
- anterior mediastinal, posterior mediastinal → thoracic duct,
→ right lymf. duct
- bronchomediastinal → throacic duct
→ right lymf duct
head and neck:
regional lymph nodes – deep cervical nodes
efferents → jugular trunk → thoracic duct,
→ right lymph. duct
upper limb (and adjoing part of trunk)
regional lymph nodes – axillary lymph nodes
efferents → subclavian trunk → thoracic duct,
→ right lymph. duct
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