11 Salivary Gland Disorders Flashcards
1 During what week of embryogenesis does the parotid gland develop?
The 7th embryonic week
2 Where does the parotid gland originate during development, and what is its relationship to the facial nerve?
The parotid gland originates at the site of the eventual duct orifice and grows in a posterior direction. The facial nerve develops in an anterior direction. The facial nerve eventually becomes surrounded by parotid gland tissue.
3 What are the different types of acini in the salivary glands?
There are three types: serous acini are found in the parotid, mucous acini in the sublingual and minor salivary glands, and mixed acini, which are found in the submandibular gland.
4 Describe the salivary gland duct system. (▶ Fig. 11.1)
An acinus is the main secretory component that is composed of a central lumen surrounded by acinar cells that produce saliva. Intercalated ducts form early connections between acini. Both acini and intercalated ducts are lined with myoepithelial cells that help to contract and propel saliva forward. Intercalated ducts feed into larger striated ducts and then into excretory ducts.
5 What is the relationship of lymph nodes to the salivary glands?
Lymph nodes develop within the pseudocapsule of the parotid gland, leading to intraparotid lymph nodes. No other salivary gland has intraglandular lymph nodes.
6 Where are intraparotid lymph nodes typically located?
The parotid gland is the only salivary gland with lymph nodes actually within the gland. Most intraparotid lymph nodes lie within the superficial lobe, although they are present in both the superficial and deep lobes.
7 Describe the path of the Stenson duct (parotid duct).
It originates from superficial portion of parotid gland, travels anteriorly on the masseter muscle and buccinator fat pad, and then travels medially to pierce the buccinator muscle. The duct empties lateral to the second maxillary molar.
8 Where does the Wharton duct (submandibular duct) empty into the oral cavity?
The submandibular duct empties just lateral to the lingual frenulum.
9 What fascial layer forms the parotid fascia?
The parotid fascia is continuous with the superficial layer of the deep cervical fascia.
10 Describe the fascial connections of the superficial musculosaponeurotic system (SMAS) and its relationship to the parotid gland.
The SMAS gives support to the many muscles of facial expression. Over the parotid gland, it is located just superficial to the parotid fascia.
11 What is the autonomic nerve supply of the parotid glands?
The parasympathetic nervous system supplies the parotid gland via the glossopharyngeal nerve (cranial nerve IX). The sympathetic nervous system supplies the gland via the superior cervical ganglion.
12 Describe the path of the parasympathetic inner vation of the parotid gland. (▶ Fig. 11.2)
Parasympathetics that are part of the glossopharyngeal nerve (tympanic branch) enter the middle ear through the tympanic canaliculus as the Jacobson nerve. They then exit the middle ear cavity and travel through the middle cranial fossa as the lesser petrosal nerve. The lesser petrosal nerve exits the skull base through the foramen ovale and travels to the otic ganglion. After synapsing in the otic ganglion, postsynaptic fibers are carried via the auriculotemporal nerve to the parotid gland.
13 Define accessory parotid gland tissue.
Accessory parotid tissue lies anterior to the main parotid gland between the skin and the masseter muscle.
14 What are important anatomical landmarks for identification of the facial nerve during parotidectomy?
The facial nerve can be located via its relationships to the tragal pointer, tympanomastoid suture line, and the attachment of posterior digastric muscle to digastric groove, or it can be identified distally and dissected in a retrograde fashion or drilled out from the mastoid bone and traced anterograde.
15 How does the parotid gland change histologically with age?
There is an increase in adipose cells in the parotid parenchyma with age.
16 In which anatomical triangle is the submandibular gland located, and what are its boundaries?
The submandibular triangle: its boundaries are the anterior and posterior bellies of the digastric muscle and the inferior aspect of the mandible.
17 What nerve carries the parasympathetic supply to the submandibular gland?
The chorda tympani carries parasympathetic fibers to the submandibular and sublingual glands via the lingual nerve.
18 Secretomotor function of the submandibular and sublingual glands is controlled by which nerve?
Parasympathetic contribution of facial nerve (nervus intermedius) via the chorda tympani
19 Where is the lingual nerve found during a submandibular gland excision?
The lingual nerve is found deep to the submandibular gland. With inferior retraction of the gland and anterior retraction of the mylohyoid muscle, the lingual nerve and the submandibular ganglion can be exposed.
20 What is the relationship of the lingual nerve to the submandibular duct in the floor of mouth? (▶ Fig. 11.3)
The lingual nerve courses from a posterolateral to anteromedial position, passing below the Wharton duct.
21 Where are the facial artery and vein found in relation to the submandibular gland?
The facial vein is found on the lateral surface of the submandibular gland; the facial artery is located on the posterior surface of the gland and is often ligated on both the superior and inferior aspect of the gland during submandibular gland excision.
22 Name the ducts through which the sublingual gland drains.
The sublingual gland drains into the mouth via the smaller duct of Rivinus (which empties into the floor of the mouth or into submandibular duct) and larger duct of Bartholin (empties into submandibular duct).
23 What structures border the sublingual gland?
The sublingual gland is bordered by the mandible, genioglossus muscle, and mylohyoid muscle.
24 What structures are important to be aware of during excision of the sublingual gland?
The lingual nerve and Wharton (submandibular) duct run between the sublingual gland and the genioglossus muscle.
25 Where are most minor salivary glands located?
The hard palate mucosa harbors most of the mouth’s minor salivary glands.
26 What are the functions of saliva?
There are many functions of saliva, the most important being lubrication of food, buffering and prevention of caries, mineralization of teeth, antibacterial and bactericidal function, digestion, and taste.
27 List the order of salivary gland saliva production from most serous to most viscous.
In order from most serous to most viscous: parotid gland > submandibular gland > sublingual gland > minor salivary glands
28 What are the important physical examination findings to assess when evaluating a salivary gland mass?
One should appreciate the size of the mass, invasion of overlying skin, mobility versus fixation, tenderness to palpa tion, facial nerve function, trismus, pharyngeal fullness, and whether there is evidence of a primary skin or scalp lesion.
29 Typically, how large must a parapharyngeal mass be to visualize it intraorally?
Usually, a parapharyngeal mass must be at least 3.5 cm to visualize it intraorally.
30 Name the key surgical landmarks associated with the location of the facial nerve during parotidectomy?
● The facial nerve lies 1 to 1.5 cm deep and inferior to the tragal pointer. ● The attachment of the posterior belly of the digastric muscle to the digastric ridge identifies the plane of nerve. ● The nerve lies 6 to 8 mm deep to the tympanomastoid suture.
31 What is the pathophysiology of Frey syndrome after parotidectomy?
Postganglionic parasympathetic secretomotor fibers carried on the auriculotemporal nerve, which normally innervate the parotid gland tissue, aberrantly reinnervate sweat glands of the overlying skin.
32 Name an objective test for Frey syndrome.
The Minor starch-iodine test is an objective measure of gustatory sweating. The preauricular region is coated with iodine, allowed to dry, and then dusted with starch. The patient is then given a sialagogue, and a positive test (indicating Frey syndrome) results in dark blue spots where sweat has dissolved the starch and reacted with iodine.
33 What are the treatment options for Frey syndrome?
Treatment options are broad and depend on the patient’s discomfort level. Options range from observation and use of antiperspirant, to medications such as glycopyrrolate, or more invasive therapy such as botulinum toxin injection or tympanic neurectomy.
34 What techniques can be used to reduce post parotidectomy gustatory sweating?
The most important surgical techniques to prevent Frey syndrome are raising a thick skin flap and doing only a partial superficial parotidectomy.
35 What additional techniques are being used to try to reduce post parotidectomy gustatory sweating?
Rotational sternocleidomastoid flaps, fat transfer, Alloderm implants, and superficial musculoaponeurotic system in terposition are all being used.
36 Which salivary gland is most susceptible to acute bacterial sialadenitis?
The parotid gland
37 Which population groups are most commonly affected by acute suppurative sialadenitis?
Patients who are medically debilitated, postoperative, and/ or patients with severe dehydration
38 Which surgical patients are most commonly affected by acute suppurative sialadenitis?
Patients who have undergone major abdominal surgery and hip replacement/repair, likely a result of poor oral intake attributable to their debilitated state, are most commonly affected.
39 Why does the saliva produced by the parotid gland make this gland more prone to sialadenitis compared with the submandibular and sublingual glands?
Parotid saliva is mostly serous compared with the mucinous saliva produced by the submandibular and sublingual glands. Serous saliva lacks antibodies, acid, and enzymes with antimicrobial properties.
40 In hospitalized patients, what is the most com monly cultured organism in acute suppurative sialadenitis?
Staphylococcus aureus
41 When is imaging of acute suppurative parotitis recommended?
Imaging is indicated after failure to respond to antibiotics or if signs, symptoms, and physical examination raise concern for a parotid abscess.
42 What is the best initial treatment of acute suppurative sialadenitis?
Empiric antibiotics with both aerobic and anaerobic cover age, sialagogues, warm compresses, parotid massage, pain medication, and rehydration
43 What is the recommended treatment of a parotid abscess?
Surgical drainage through a standard parotidectomy exposure is recommended. When making incisions in the parotid fascia, it should be done parallel to facial nerve branches to minimize risk of damage to the nerve.
44 What is the most common symptom that raises concern for sialolithiasis?
Pain and swelling of the salivary glands, especially associated with eating
45 Which salivary gland carries the highest risk for salivary calculi formation?
The submandibular gland is the most common location of salivary calculi as a result of increased calcium concen tration, higher pH, more mucinous saliva, and potential anatomical factors (e.g., length, gravity).
46 What imaging options are available for diagnosis of sialolithiasis?
There are many choices. Plain X-ray offers little extra information other than the presence of a radiopaque stone. Sialography can give information on strictures, dilations, or filling defects of the ductwork. Ultrasound can be done if a radiolucent stone is suspected. CT often offers the most complete information.
47 Which salivary calculi are most often radiopaque and which are radiolucent on standard X-ray?
Submandibular stones. 80% of parotid stones are radiolucent.
48 What are the treatment options for sialolithiasis?
Conservative treatment is a valid option. This includes sialagogues, heat, massage, and increased hydration. For larger stones that will not pass with conservative measures, bedside sialotomy, sialendoscopy, or lithotripsy are options. Gland excision is final treatment option for refractory disease.
49 What is the number one cause of chronic sialadenitis?
Parotid duct obstruction secondary to sialolithiasis
50 What is the best treatment for chronic sialadenitis?
No treatment is consistently successful. Antibiotics, mas sage, warm compresses, and sialagogues may be tried. Ultimately, if conservative measures fail, the affected gland should be surgically resected.
51 Patients with chronic sialadenitis should be moni tored for what serious condition?
Patients with chronic sialadenitis are at an increased risk for salivary duct carcinoma.
52 When should sialorrhea be managed as an abnormal condition in the pediatric population?
Sialorrhea is associated with the balance of oral control of secretions and swallowing. Up until about 18 months of age, sialorrhea is a normal event because of poor neuro muscular control. If it is still present by 4 years of age, a patient should undergo further workup.
53 What other medical conditions are associated with sialorrhea?
Conditions associated with poor neuromuscular control, which cause difficulty swallowing secretions, can be associated with sialorrhea, most commonly in children with cerebral palsy. It is also seen in adults with amyotrophic lateral sclerosis, Parkinson disease, and history of stroke.
54 How can sialorrhea be treated medically?
Anticholinergics: PO glycopyrrolate and topical scopolamine.
Botox injections (require repeated injections)
55 Describe the side effects of anticholinergic med ications.
Urinary retention, increased body temperature/decreased perspiration, tachycardia, xerostomia (increased risk of dental caries), vision changes, confusion, respiratory sup pression, mydriasis, and constipation are all common side effects of anticholinergics.
56 What are the surgical options for treatment of sialorrhea?
Removal of salivary tissue can be done via bilateral submandibular gland excision and parotid duct ligation. Transection of the chorda tympani can also decrease salivary output. The submandibular and parotid ducts can be rerouted to decrease output into the oral cavity.
57 Define the difference between sialorrhea and ptyalism.
These terms are often used interchangeably. By strict definition, though, sialorrhea means excessive flow of saliva. Usually, it is secondary to administration of medications such as antipsychotics, anticonvulsants, anticholinesterases, or other parasympathomimetic medications. Excessive flow can also be related to medical conditions such as pregnancy, gastroesophageal reflux disease, and oral ulceration/irritation. Ptyalism is the act of drooling and the excessive production of saliva. Historically, it is most commonly used in pregnancy as ptyalism of pregnancy.
58 What is the most common cause of xerostomia?
By far, the most common cause is medication side effect.
59 What is one of the most important preventative treatments to reduce complications of xerostomia from head and neck radiation?
Topical fluoride and excellent oral hygiene are used to prevent the formation of dental caries because saliva is protective of the teeth.
60 What drug is used to treat xerostomia?
Pilocarpine, a parasympathomimetic drug that acts on the M3 acetylcholine muscarinic receptor
