Ch 5 Salivary Glands Flashcards
Differentiate exocrine + endocrine glands?
Exocrine: secretes substances through ducts
Endocrine: secretes substances directly into bloodstream
Are salivary glands exocrine or endocrine glands?
Exocrine - they produce saliva through ducts
What are the 3 major paired glands?
-Submandibular glands
-Parotid glands
-Sublingual glands
What is the purpose of salivary glands?
They secrete enzymes for chewing + digestion
What are some indications on why we would scan the salivary glands?
-Painful/swollen
-Palpable mass
What general pathologies could be found in the salivary glands?
-Abscesses (due to infection/inflammation)
-Cysts
-Neoplasia (abnormal growth of cells)
-Sialolithiasis
Which salivary gland is the largest?
The parotid gland
Where is the parotid gland located?
In the parotid space which is anterior + inferior to the ear
Explain the parts of the parotid gland?
-The inferior portion (lower 2cm) is called the tail
-There are superficial + deep lobes separated by the facial nerve
-Has a fibrous capsule
What is the role of the parotid gland?
Secretes saliva into the oral cavity via the parotid duct (aka stensen duct) at approx the level of the 2nd upper molar
Another name for parotid duct?
Stensen duct
Tumors/neoplasms are m/c in which salivary gland?
Parotid
List parotid gland variations that can occur?
-Accessory glands
-Facial process (anterior extension)
-Ectopic
-Duplication
-Congenital agenesis (uni or bilateral)
What is the sonographic appearance of the parotid gland?
-Homogeneous
-Superficial
-Increased echogenicity compared to muscles
-Intraparotid lymph nodes are common to see
(typically the deep posterior lobe is NWS, can try decreasing frequency)
What is the Duct of Rivinus?
-A collection of 8-20 smaller excretory ducts that drain the sublingual glands
-Largest + major sublingual duct is called the Bartholin duct
What is the major sublingual duct?
The Bartholin duct
(this is the largest of the Rivinus ducts)
What is the SF of sublingual glands?
-Echogenic
-Triangular appearance in submental space
-Homogeneous
Where is the submandibular gland (SMG)?
Lies medial to the mandible
What is the role of the SMG?
-Secretes saliva into the oral cavity via the submandibular duct (aka wharton’s duct), lateral to the frenulum of the tongue
-Produces the majority of the saliva in the mouth (70%)
Another term for submandibular duct?
Wharton’s duct
Which salivary gland produces the majority of saliva in the mouth?
SMG
Does the SMG have a capsule?
Yes! Has a fibrous capsule
(does NOT usually contain lymph nodes)
What is the m/c SMG variation?
Congenital absence (often accompanied by compensatory hypertrophy)
What is the SF of the SMG?
-Superficial (anterior to muscles)
-Homogeneous
-More echogenic than muscles
(place the probe under the angle of the mandible, in the submental area, to image the SMG)
List 6 specific pathologies we covered that can occur in the salivary glands?
-Sialolithiasis (stone)
-Sialadenitis (inflammation)
-Warthin’s tumor
-Pleomorphic adenomas
-Sjogren syndrome (autoimmune condition)
-Mikulicz syndrome (gland enlargement)
What is sialolithiasis?
-Stones inside the ducts or parenchyma of the salivary glands
-M/c salivary gland disease
-M/c in the SMG (others in the parotid)
-M/c in males aged 30-60
What is the m/c salivary gland disease?
Sialolithiasis
(m/c in the SMG b/c its secretions are thicker + travel upward towards the mouth, whereas the parotid gland secretions travel downwards to the mouth + are less thick)
What is the clinical presentation of sialolithiasis?
-Recurrent pain + swelling in the affected area of the gland (often associated with eating due to duct obstruction)
-Can cause infections (bacterial sialadenitis)
-Chronic obstructions can cause the gland to undergo fatty atrophy + become asymptomatic
What is the SF of sialolithiasis?
-Echogenic linear focus with posterior shadow (small stones may not shadow)
-Dilated duct if obstructed
-Gland enlargement
-If chronic the gland may appear echogenic, fatty + atrophic
(intraoral probes can be used for better vis)
What is sialadenitis?
Inflammation of the salivary glands due to a variety of potential causes
List causes of sialadenitis?
-Acute bacterial or viral sialadenitis
-Chronic sialadenitis
-Sialolithiasis (m/c - causing obstructive sialadenitis)
-Miscellaneous causes of acute sialadenitis include immunosuppression + dehydration
Differentiate the SF of acute vs chronic sialadenitis?
Acute: enlarged, hypoechoic, hyperemic, possibly duct dilatation
Chronic: atrophic, diffusely hypoechoic with irregular margins
Another term for pleomorphic adenomas?
Benign mixed tumor
What is the m/c salivary gland tumor + its m/c location?
Pleomorphic adenomas in the parotid gland
What are pleomorphic adenomas?
-Benign mixed tumor
-M/c salivary gland tumor (70-80% benign)
-M/c in parotid gland 84% (then SMG 8%, minor salivary glands 6%, sublingual glands 1%)
-Occurs in middle age people
What are pleomorphic adenomas associated with?
Prior neck irradiation
SF of pleomorphic adenomas?
-Hypoechoic mass
-Posterior enhancement
Treatment of pleomorphic adenomas?
Surgery (partial or total parotidectomy) due to risk of malignant transformation
What is warthins tumor + where does it m/c occur?
-Benign tumor (1% malignant transformation)
-M/c from parotid gland + favors the tail
What is warthins tumor associated with?
Smoking + irradiation
SF of warthins tumor?
-Bilateral in 10-15% cases
-Well defined, ovoid lesion with multiple irregular cystic areas
-Larger lesions (>5cm) have more cystic components
-Hypervascular
Treatment of warthins tumor?
-Surgery
-Conservative management
Another term for sjogren syndrome?
Gougerot-sjogren
What is sjogren syndrome?
-Autoimmune condition of the exocrine glands that produce tears or saliva
-M/c in females (9:1 ratio) aged 40-50
Clinical presentation of sjogren syndrome?
-Dry eyes + inflammation (xerophthalmia)
-Dry mouth (xerostomia)
-Bilateral parotid enlargement
SF of sjogren syndrome?
Early stage: normal or enlarged gland + hyperechoic
Late stage: atrophic gland with multi cystic appearance
What is mikulicz syndrome?
-On IgG4 related disease spectrum
-Non specific inflammatory enlargement of at least 2 salivary + lacrimal glands
Clinical presentation of mikulicz syndrome?
-Bilateral painless, symmetrical swelling of the lacrimal + salivary glands
-Xerostomia (dry mouth)
-Xerophalmia (dry eyes)
SF of mikulicz syndrome?
Enlargement of the lacrimal + salivary glands
What causes salivary gland enlargement?
Many causes!! Such as obstruction, infection, inflammation, immune, neoplastic, infiltrative + congenial causes
(SF depends on the condition that causes the enlargement)
List the duct with each salivary gland?
Parotid: stensen’s duct
SMG: wharton’s duct
Sublingual: sublingual ducts (major one is the bartholin duct)
What is the thymus gland?
-NOT a salivary gland
-Plays a role in immune function
-Releases thymosin (a hormone necessary for T cell production, it will produce all the T cells by the time we reach puberty)
Is it normal to see the thymus?
In children it is largest, it slowly gets replaced by fast after puberty + is no longer is seen
Where does the thymus lie?
In the retrosternal area
(can be ectopic or have a cervical extension)
