Transcript Lymphatic System

Lymphatic System
and
Axillary Lymph Nodes
Dr Rania Gabr
Objectives
 Discuss Lymph, Lymphatic vessels, Lymphatic nodules
and Lymphoid organs.
 Enlist functions of lymphatic System.
 Explain Lymphatic circulation.
 Discuss Main lymphatic channels.
 Describe the axillary lymph nodes
 Describe the Inguinal Lymph nodes
- The lymphatic system
carries excess of the
extracellular fluid back to
the venous system.
- This fluid is the result of
filtration from capillaries.
- - The lymphatic system
consists of :
1.lymphatic vessels,
2.lymph nodes,
3.lymphatic ducts
4.Spleen.
1.
Lymph vessels
- The lymph capillaries start as blind ended vessels that collect to
form lymphatic vessels which are similar to the small veins
(contain smooth muscles) but contain valves so it has beaded
appearance.
- In the intestine the lymphatics are called lacteals.
Superficial lymphatic vessels:
* Present on the deep
surface of the epithelium.
* They run parallel to the
superficial blood vessels of
the skin.
* They then join together to
form larger vessels, which
pierce the deep fascia to join
the deeper vessels.
Deep lymphatic
vessels:
* They are deep to the deep fascia,
parallel to the major blood vessels.
* These are larger than the
superficial vessels and have thick
walls and valves.
2. Lymph Nodes
Definition:
- They are small oval
bodies along the course
of lymphatic vessels.
Site:
- They form groups
especially in the neck,
axilla, thorax, abdomen,
and groin.
Structure:
- It has two surfaces:
a. Convex (outer) surface:
- This surface receives afferent
lymphatics.
- Filtrations of its contents
occur inside the lymph node.
b. Concave (inner) surface:
- It is called the hilum.
- This surface gives exit to
an efferent lymphatic in
addition to the presence of
a small artery and vein.
Functions of lymph nodes:
1. Act as a filter as they prevent micro-organisms and certain substances
from entering the blood stream.
2. Formation of lymphocytes.
3. Formation of antibodies.
4. In case of infection or malignancy, the lymph nodes become enlarged
and change in consistency.
3. Lymphatic Duct
- There are two lymphatic ducts thoracic duct and right
lymphatic duct.
a. Thoracic duct
- It begins in the cisterna chili
in the abdomen (in front of the
lumbar vertebrae)
- It ascends through the
posterior abdominal and
thoracic walls (deviating to the
left side).
- It terminates at the junction of
left subclavian and left internal
jugular veins.
- It drains lymph from all the
body except the upper right
quadrant.
b. Right lymphatic duct
- It is much smaller in
size.
- It drains lymph from the
upper right quadrant
(right side of the head
and neck, right upper
limb, and right side of
the chest)
- It terminates at the
junction of right
subclavian and right
internal jugular veins
Other lymphatic aggregations:
They are seen in:
- tonsils.
- Mucous membrane of the intestine (Peyer's patches).
- Spleen.
- Thymus gland.
All parts of the body posses lymphatics EXCEPT:
• C.N.S: its lymphatics are replaced by perivascular spaces that are
connected with the subarachnoid space.
• Bone marrow.
• Spleen.
Internal
ear.
Epidermis.
Cartilage.
Bone.
• On the other hand, certain parts of the body have a rich network of
lymphatics e.g.
• dermis of the skin,
• mucous membranes,
• serous membranes
• glands.
Axillary Lymph Nodes
Divided into 5 main groups:
1- Pectoral (Anterior) group
2- Scapular (Posterior) group
3- Lateral group
4- Infraclavicular LNs
5- Apical group
1- Pectoral (Anterior) group:
Site:
on lower border of pectoralis minor.
Afferents:
from front of upper ½ of trunk, and
breast.
2- Scapular (Posterior) group:
Site:
along subscapular artery
Afferents:
1- from the back of the upper ½ of the
trunk, and
2- axillary tail of
breast.
3- Lateral group:
Site:
Along the axillary vessels.
Afferents:
From upper limb.
4- Infraclavicular LNs:
Site:
Below clavicle
Afferents:
From the upper part of the breast.
5- Apical group:
Site:
At the apex of axilla
Afferents:
from previous groups.
Efferents form the subclavian
trunk which enters the thoracic
duct or right lymph trunk
Applied note:
Infection or malignancy
in the upper limb or
breast gives swelling in
the axilla due to
involvement of axillary
LNs.
• Virchow`s lymph node????
Inguinal lymph nodes
I- Superficial inguinal LNs:
Site: In the proximal region of the
femoral triangle. Below the
inguinal ligament
No: 12- 20
Two groups:
A- Horizontal group:
i- Medial:
It drains: Anterior abdominal wall
below umbilicus, lower part of
anal canal, external genitalia
(male and female).
ii- Lateral:
It drains; buttock and back below
B- Vertical group:
It drains the lower limb.
It is present at the end of the great
saphenous vein.
All the above groups of LNs send
efferents to deep inguinal and
external iliac LNs.
Inguinal lymph nodes cont.
II- Deep inguinal LNs:
- Site: Deep to deep fascia on
the medial side of the femoral
vein.
- No: 1-3. One of them may lie
in the femoral canal (lymph
node of Cloquet).
- Afferent: from deep
lymphatics of the lower limb
and from superficial inguinal
LNs.
- Efferent: to external iliac LNs