Lymph nodes

Question 1

Do lymph vessels have valves?

Answer 1

Yes

Question 2

What is lymph?

Answer 2

Thin watery fluid that enters the capillaries and flows in lymph vessels

Question 3

What are the two major groups of lymphatic vessels in the head and neck?

Answer 3

1. SuperficialVessels
   • The superficial vessels drain lymph from the scalp, face and neck into thesuperficial ringof lymph nodes at the junction of the neck and head
2. Deep Vessels
   • The deep lymphatic vessels of the head and neck arise from thedeep cervical lymph nodes.They converge to form theleft and right jugular lymphatic trunks:

○ Left jugular lymphatic trunk: combines with the thoracic duct at the root of the neck. This empties into the venous system via the left subclavian vein.
○ Right jugular lymphatic trunk: forms the right lymphatic duct at the root of the neck. This empties into the venous system via the right subclavian vein.

Question 4

Locate and identify the major groups of lymph nodes of the head and neck

Answer 4

Superficial lymph nodes:

1. Occipital (1-3 nodes). Drains the Posterior scalp
2. Superficial Parotid (up to 10 nodes). (retroauricular, anterior auricular and superficial auricular) Drains scalp, face, external ear, lacrimal gland
3. Facial (up to 12 nodes): Located along the length of the facial vein. 4 sub-groups: infraorbital (molar), nasolabial, buccal, mandibular
4. Submental (medial lip, incisors, tip of tongue)
5. Submandibular: Buccal node (face):upper lip, lateral part of lower lip, maxillary & mandibular teeth, labial & buccal gingiva, margin of tongue

Deep Lymph Nodes:
1. Deep Parotid (up to 10 nodes): Deep to parotid gland. Drains: middle ear, auditory tube, parotid gland

2. Deep Retropharyngeal (up to 3 nodes). Posterior to pharynx. Drains: palate, paranasal sinus, nasal cavity

Question 5

Which nodes are responsible for lymphatic drainage of the neck?

Answer 5

Two prominent nodes in the neck that can be classified as superior and inferior. Divided by the omohyoid muscle
• Jugulodigastric nodes (oral cavity, also superior neck)
• Jugulo-omohyoid (inferior neck)

Question 6

Describe the pattern of drainage of lymph from the head and neck

Superficial and deep nodes

Answer 6

Superficial ring: posterior head to chin
• Submental nodes (medial lip, incisors, tip of tongue)
• Submandibular: Buccal node (face):upper lip, lateral part of lower lip, ALL teeth, labial & buccal gingiva, margin of tongue)
• Parotid nodes (preauricular – eyelids, cheek, ear)
• Postauricular nodes (ear)
• Occipital nodes (posterior scalp)

• All drain into deep cervical nodes (directly or indirectly)

Deep lymph nodes of the head and neck: Deep cervical nodes
• Drains the head and neck
• Rungs along the internal jugular vein in neck, and is deep to SCM
• It joins with the thoracic duct and internal jugular vein

Question 7

Identify tonsillar tissue in the head and neck region,

Answer 7

1. Palatine tonsils
   • Different to lymph nodes
   • Masses of lymphoid tissue, not located along lymph vessels
   • This lymphatic tissue responds to pathogens that may be ingested or inhaled
   • Waldeyer’s tonsillar ring refers to the collection of lymphatic tissue surrounding the superior pharynx.
2. Lingual tonsils
   • Located on the posterior dorsum of the tongue
3. Pharyngeal tonsils
   • also called the nasopharyngeal/adenoid tonsil, located in the roof of the nasopharynx

Question 8

Detail the types of saliva produced by the parotid gland, including its blood supply

Answer 8

Type of saliva:
Serous

Location:
Anterior to the ramus of mandible, and finishes posterior to the mastoid process

Drainage:
Deep parotid lymph nodes

Blood supply: external carotid artery

Question 9

Detail the types of saliva produced by the submandibular gland, including its blood supply

Answer 9

Type of saliva:
Mucous and serous

Location:
Either side of mylohyoid muscle, inferior to body of ramus.

Sublingual caruncle is the opening for the submandibular duct

Drainage:
Submandibular lymph nodes

Blood supply: facial artery

Question 10

Detail the types of saliva produced by the sublingual gland, including its blood supply

Answer 10

Type of saliva:
Mucous

Location:
Superior surface of mylohyoid muscle, and is separated from oral cavity by thin layer of mucosa

Enters to sublingual folds or whartons duct.

Drainage:
Submandibular lymph nodes

Blood supply: lingual/ facial artery

Question 11

Detail the types of saliva produced by minor salivary glands, including the types of minor salivary glands

Answer 11

Pharyngeal, palatine and labial glands

Type of saliva:
Mucous

Location:
Scattered across mucosa