Lymphatic System

Question 1

Function

Answer 1

• Drains Fluid
• Defense Mechanism
• Absorbs & transports fat

Fluid passes from blood vessel capillaries to
interstitial spaces
• Lymph capillaries collect fluid and transport it
to the venous system
• On the way. fluid passes through lymph nodes
– Filter
– Monitoring lymph for antigens – involves
lymphocytes

Question 2

Primary lymphoid organs Secondary lympoid organs

Answer 2

Two kinds of lymphoid organs:

Primary = bone marrow and thymus, which is where lymphocytes originate or mature (never exposed to pathogens)

Secondary = the ones that react to antigens such as lymph nodes, spleen (different then the lymph nodes because it does not have lymphatic vessles nor efferent/afferent and mainly filters/monitors blood for pathogens

Question 3

MALT

Answer 3

Mucosa Assocaited Lymphatic Tissues

Mucosa attracts the pathogens they stick to it, and that is how they get to the lymphoid organs that are associated with the MALT

NO AFFERENT VESSELS, ONLY EFFERENT

Examples are peyer’s patches in the ilium and tonsils

Question 4

Lymphocytes

Answer 4

White blood cells formed in lymphatic tissue

• Originate in Primary Lymphoid Organs (Bone Marrow & Thymus)
– Naive
• Lodge in Secondary Lymphoid Organs & circulate in blood stream
– Reactive – respond to antigens

Question 5

Lymph

Answer 5

• Usually clear

• Mostly same constituents as blood plasma
(protein and lymphocytes)

• From small intestine contains fat and other
substances – callled Chyle

Question 6

Lymph Nodes/Vessels

Answer 6

The valves in the lymphatic vessels help prevent back
flow and smooth muscles.

The contraction of striated muscles help move the
lymph through the body.

They’re in the intestine as mesenteric lymph nodes so
these would collect from the peyer’s patches.

Question 7

Areas with No Lymphatic Vessels

Answer 7

• Bone marrow
• Brain
• Cartilage
• Cornea
• Epidermis (epithelial component of the integument)
and its derivatives (e.g. hair, nails)
• Globe of the eye
• Inner ear
• Meninges
• Spinal cord
• Spleen

Question 8

Clinical Importance

Answer 8

• Nodes and vessels draining infected area become inflamed
– Lymphangitis (“swollen glands”)
– Usually painful

• Cancer cells spread via lymphatic system
– Usually painless
– Enlargement of nodes
– Lymphedema

Question 9

Principal Lymph Nodes

Answer 9

Deep Nodes:
Related to the aorta, celiac trunk and inferior mesenteric arteries

Axillary Lymph Nodes:
around the axilla (armpit)

***Pericardial Ring at the base of
the head

Cervical Nodes
two lines of lymph nodes along the internal and external jugular vein

Tracheal Nodes

Question 10

Thoracic and Right Lymphatic Duct Drainage

Answer 10

Pathway of the thoracic duct

it begins in the abdomen angle as the cistern chili it enter the thorax via the aorta hiatus of the diaphragm (T12) – it travels between the aorta and the azygos vein and travels to the esophagus – and starting a little
to the right it crosses the midline around the sternal angle

then it passes posterior through the common carotid and internal jugular vein on the left side and then it loops around and drains into the subclavian right where it is meeting with the internal jugular where it is forming the brachiocephalic vein.

the lymph on the right side of the thoracic region draining into the right thoracic duct and right subclavian vein.

Question 11

Ring of Nodes in Head

Answer 11

Ring around head:
Occipital
Mastoid
Preauricular/Parotid
Submandibular
Submental

Occipital & Matoid
to Superficial - Superficial cervical lymph nodes drain– along EXTERNAL into Jugular V. Drain into Deep Cervical Lymph Nodes

Cervical Chain

Others to Deep
Cervical Chain

Question 12

Jugulodigatric and Jugulo-omohyoid Nodes

Answer 12

jugulodigastric node = where the internal jugular
crosses the posterior belly of the digastric muscle – this receives lymph from the palatine tonsils – these nodes become inflamed when there
is a respiratory infection.

jugulo-omohyoid node = more inferior and that receives lymph from the tongue ( should be aware of tongue cancers )

Question 13

Level system

Answer 13

evaluates spread of head and neck tumors

Question 14

Drainage of Tongue

Answer 14

Crossover of midline R & L lymphatics: disease on
one side can spread to the other side

Here you can see why cancer of the tongue can be particularly devastating – because there is this crossover in the drainage – so it
may metastasis to lymph nodes on either sides of the neck

Posterior 1/3 will drain via the retropharyngeal
nodes ( cancer in the posterior of posterior 1/3 of the
tongue will be drained)

retropharyngeal nodes anterior to C1 vertebrae.

Palatine tonsls go to the deep cervical nodes (specifically jugulo-digastric) -

Anterior but still kinda posterior part of the
tongue we also have deep cervical nodes.

Laterally sides of tongue to the submandibular nodes

Tip of the tongue would drain into the submental nodes.

can palpate submandibular and sub mental nodes.

Question 15

Submandibular Nodes

Answer 15

• Receive lymph from
      – Medial corner of orbit
      – Most of external nose
      – Medial part of cheek
      –Upper lip
      – Lateral lower lip (medial lower lip to submental 
          nodes)
     –Gingivae
     – Teeth
     – Tongue

Question 16

Deep Horizontal Ring of Nodes

Answer 16

• Lingual
– Not always present
– Superficial to hyoglossus or at base of genioglossus
• Paratracheal (around the trachea)
• Pretracheal ( front of the trachea)
• Prelaryngeal (in front of the larynx)
• Infrahyoid (below the hyoid bone)
• Retropharyngeal (in the retropharyngeal space)

They are also not on one level – they are
bouncing around superiorly and inferiorly

Question 17

Lymphatic Rings and Chains in Head and Neck

Answer 17

There are two
chains
- the superficial cervical chain will be traveling along the external jugular vein.

• deep cervical chain is traveling with the internal
  jugular vein.

horizontal superficial ring around the base bof the skull and a deeper horizontal ring which goes
around the viscera around the pharynx.

Both rings will eventually drain into the deep cervical chain which travels with the internal jugular vein.

Question 18

Cisterna chyli

Answer 18

Confluence of lymphatic trunks in abdomen;

All of the lymph from the lower body flows into the
cisterna chyli eventually. The lymph from small intestine is gathered by Peyer’s patches, and it includes fats so it’s milky-white and is thus called Chyle.

The lymph from cisterna chyli gets diluted as it joins with fluids from other parts of body and then it drains to the junction of left internal jugular and subclavian veins.

Question 19

Drainage in Lungs

Answer 19

Drainage follows bronchial tree in the lungs