Lecture 8: Introduction to Lymphatics & Cervical Autonomics

What are the functions of the lymphatic system?

Drain extracellular fluid from the body and return it to the veins

Absorb lipids

Mount immune response

What is lymph composed of?

Interstitial fluid

WBCs

What are the primary lymphoid organs? What do they do?

Bone marrow and thymus

Produce B and T cells

What are the secondary lymphoid organs?

Spleen

Lymph nodes

Tonsils

What are the structures of lymphatic vessels?

Similar structure to blood vessels (intima, media, adventitia)

Has valves

Capillaries have monolayer epithelium

Afferent lymph vessels drain from ____ to ____.

Capillary beds

Lymph nodes

Afferent vessels are ONLY associated with ____.

Lymph nodes

Efferent vessels drain away from ____ and toward ____.

Lymphoid tissues

The venous system

How is the upper right side of the body lymphatically drained?

Via the right lymphatic duct

How is the left side of the body and abdomen drained?

Via the thoracic duct

What is the cisterna chyli?

A dilation in the thoracic region that receives lymph from the abdomen

How does the oral cavity drain lymph?

Via the parotid, submandibular, submental and DCLN nodes

Where are DCLN nodes found?

In the carotid sheath

What do superior DCLN nodes drain?

Anterior side of head

What do inferior DCLN nodes drain?

Posterior side of head

What do the superior and posterior DCLN form? Where does it drain?

The jugular trunk

The left jugular trunk drains into the thoracic duct while the right drains at the venous angle of the subclavian vein and internal jugular vein

What are sentinel nodes?

First node biopsied to determine a tumor stage

What is the signal of virchow node?

A node around the thoracic duct that indicates metastasis of abdominal cancer

Where do cancer cells often metastasize to?

Brain

Bone

Liver

Lungs

What is found in the white ramus communicans?

Axons of pre-ganglionic sympathetic neurons headed to the sympathetic chain

What is found in the gray ramus communicans?

Axons of post-ganglionic sympathetic neurons headed to their target organs

What is the sympathetic chain?

The connection point between sympathetic ganglia that allows sympathetic signals to travel throughout the body

Where are the superior, middle, and inferior sympathetic cervical chain ganglia found?

Superior: C2/C3

Middle: C6

Inferior: C7 (Stellate if C7 + T1)

What is Horner’s syndrome?

Disruption of the sympathetic nerves of the head caused by damage to the sympathetic chain or pre-ganglionic neurons

What are common symptoms of Horner’s syndrome?

Ptosis (eye drooping)

Miosis (constricted pupil)

Anhidrosis (decreased sweating in face)

What is an intramural ganglion?

A parasympathetic ganglion near the wall of a target organ

What is the significance of CN X Vagus?

All parasympathetic nerves to the neck and thorax are carried by CN X