04 Salivary Glands Anatomy

Question 1

With what other organs do the salivary glands share the same embryologic origin?

Answer 1

Liver, gallbladder, and pancreas (all come from mesodermal buds of foregut)

Question 2

When does parotid encase facial nerve

Answer 2

3rd month gestation

Question 3

What membrane separates the parotid gland from the submandibular gland

Answer 3

Stylomandibular membrane

Question 4

What is the blood supply to the parotid

Answer 4

Transverse facial artery (branch of STA)

Question 5

What is the major venous drainage of the parotid

Answer 5

Posterior facial vein (aka retromandibular vein)

Question 6

What is unique about the lymphatic drainage of the parotid

Answer 6

The LNs are contained w/in the gland and it is the only salivary gland with 2 layers of LNs (the superficial layer has the most LNs).

Question 7

Pathway of PARA innervation to parotid

Answer 7

Inferior salivatory nucleus via glossopharyngeal nerve –> exit jugular foramen –> travel through middle ear as Jacobson’s nerve –> travel along floor of middle cranial fossa as lesser petrosal nerve to otic ganglion –> synapse and leave via auriculotemporal branch of V3

Question 8

Where does retromandibular vein lie in relation to FN?

Answer 8

usually deep to both trunks of FN but in up to 10% of people, the vein crosses either trunk laterally

Question 9

What nodes drain tumors from the parotid

Answer 9

Just inferior to the gland and adjacent to the SCM and EJ

Question 10

Where do the hypoglossal nerve and lingual nerve lie in relation to Wharton’s duct as it exits the submandibular gland?

Answer 10

Hypoglossal lies inferiorly and lingual lies superiorly

Question 11

Which vein can be ligated and retracted superiorly during SMG excision to protect marg?

Answer 11

Anterior facial vein

Question 12

What duct drains the sublingual gland?

Answer 12

Usu there are about 10 ducts of Rivinus that drain the gland but occasionally several of these small ducts may join to form a larger sublingual/Bartholin’s duct

Question 13

What component of saliva agglutinates bacteria and activates autolysins

Answer 13

lysozyme

Question 14

What is the role of salivary peroxidase

Answer 14

helps breakdown salivary thiocyanate into products that interfere with bacterial cell metabolism

Question 15

what is the secretory potential

Answer 15

hyperpolarization of acinar cells upon stimulation by the autonomic nervous system

Question 16

what happens to the composition of saliva as it moves away from the acinar cell (primary secretion) through the duct

Answer 16

It loses sodium, acquires potassium, and becomes increasingly hypotonic. The degree of modification depends on salivary flow rate with higher rates producing saliva closer in composition to the primary secretion (less time to modify)

Question 17

What receptors are involved in salivary gland stimulation

Answer 17

muscarinic acetylcholine

Question 18

Which salivary glands contribute the highest % of resting/unstimulated saliva output

Answer 18

SMG

Question 19

Which salivary glands contribute the highest % of stimulated saliva output

Answer 19

Parotid