salivary gland diseases. anatomy ,histology, physiology , abnormality, diseases

1. Salivary Gland Diseases
BY
Dr, Ibrahim H. Ahmed .
( M. D. ) Otorhinolaryngology .

2. ‫بسم هللا الرحمن الرحيم‬
‫« الرحمن ۝ علم القرءان ۝ خلق اإلنسان ۝ علمه البيان ۝‬
‫الشمس والقمر بحسبان » . { الرحمن : 1 : 5 }‬

3. ‫ربنا واجعلنا مسلِم ْين لَك ومِن ذريتِنا أُمة مسلِمة لَّك وأَرنا مناسِ كنا وتب علَ ْينا ۖ إ َِّنك أَنت التواب الرحِيم ﴿٨٢١﴾‬
‫َ َ َّ َّ ُ َّ ُ‬ ‫ُ ِّ َّ َ َّ ً ُّ ْ َ ً َ َ ِ َ َ َ َ َ َ ُ ْ َ َ‬ ‫َ َّ َ َ ْ َ ْ َ ُ ْ َ ِ َ َ‬

5. ANATOMY
Major salivary glands Minor salivary glands
Paired
parotid , Palate ,
Submandibular , nasal cavity ,
Sublingual . oral cavity .

6. Embryology
The major salivary glands develop from the 6th-8th weeks of
gestation as outpouchings of oral ectoderm into the surrounding
mesenchyme. The parotid enlage develops first, the fully
developed parotid surrounds CN VII. Parotid gland develops in its
unique anatomy with entrapment of lymphatics in the parenchyma
of the gland. Furthermore, salivary epithelial cells are often
included within these lymph nodes.
The minor salivary glands arise from oral ectoderm and
nasopharyngeal endoderm. They develop after the major salivary
glands.
During development of the glands, autonomic nervous system
involvement is crucial; sympathetic nerve stimulation leads to
acinar differentiation while parasympathetic stimulation is needed
for overall glandular growth.

7. Major salivary glands

8. Parotid gland
The parotid gland overlies the angle of the
mandible .
Superiorly is related to zygoma .
Posteriorlly is related to cartilage of ear canal .
Medially is related to parapharyngal space

9. Facial nerve & parotid gland
The facial n. exits the stylomastoid foramen and
runs through the substance of the parotid
gland , splitting into its 5 main branches.
The plain of facial nerve is used to divide the
gland into “ superfacial “ and “ deep “ lobes .

10. Branches of facial n. within parotid gland
2 divisions:
1) Temperofacial (upper)
2) Cervicofacial (lower)
5 terminal branches:
1) Temporal
2) Zygomatic
3) Buccal
4) Marginal Mandibular
5) Cervical
3

12. The surgical landmarks of CN VII
intraoperatively :
1) Tragal pointer – points to the main trunk of CN VII proximal to
the Pes and 1-1.5 cm deep and inferior to the pointer .
2) Tympanomastoid suture – traced medially, the main trunk of
VII is encountered 6-8 mm deep to the suture line .
3) Posterior belly of Digastric muscle – is a guide to the
Stylomastoid foramen; the trunk of VII is just superior and
posterior to the cephalic margin of the muscle .
4) Styloid process – sits 5-8 mm deep to the Tympanomastoid
suture; the trunk of VII lies on the posterolateral aspect of the
Styloid near its base .

13. The Auriculotemporal nerve :
The Auriculotemporal nerve , a branch of V-3, runs anterior to the
EAM, paralleling the superficial temporal artery and vein. This nerve
carries Parasympathetic postganglionic fibers from the otic ganglion
to the Parotid gland. Thus, when this nerve is injured
intraoperatively, aberrant parasympathetic innervation to the skin
results in Frey’s Syndrome (i.e., gustatory sweating). This nerve
may be resected intentionally to avoid Frey’s Syndrome. In addition,
the Auriculotemporal nerve provides sensory innervation to the
parotid capsule, and the skin of the auricle and temporal region. As
a result, referred pain from parotitis can involve the auricle, EAM,
TMJ, and temples.

14. Parotid duct
Stensen’s duct (parotid duct) arises from the anterior
border of the Parotid and runs superficial to the
masseter muscle, then turns medially 90 degrees to
pierce the Buccinator muscle at the level of the
second maxillary molar where it opens onto the oral
cavity. The buccal branch of CN VII runs with the
parotid duct. The duct measures 4-6 cm in length
and 5 mm in diameter.

15. Parotid Gland

16. Submandibular gland
Superolaterally , the submandibular gland abuts
the body of the mandible
Medially the lingual and hypoglossal nerves,
Anteriorly , the mylohyoid muscle .
Posteriorly , the tail of parotid gland .
Lateraly , marginal branch of facial n.

17. The Submandibular duct (Wharton’s duct) :
Wharton’s duct exits the medial surface of the gland and runs
between the Mylohyoid (lateral) and Hyoglossus muscles and on to
the Genioglossus muscle.
Wharton’s duct empties into the intraoral cavity lateral to the
lingual frenulum on the anterior floor of mouth. The length of the
duct averages 5 cm.
The Lingual nerve wraps around Wharton’s duct, starting lateral
and ending medial to the duct, while CN XII parallels the
Submandibular duct, running just inferior to it.
The identification of CN XII, the Lingual nerve, and Wharton’s duct
is absolutely essential prior to resection of the gland.

18. Submandibular Gland

19. Sublingual Gland
This gland lies just deep to the floor of mouth mucosa between
the mandible and Genioglossus muscle. It is bounded
inferiorly by the Mylohyoid muscle.
Wharton’s duct and the Lingual nerve pass between the
Sublingual gland and Genioglossus muscle.
The Sublingual gland has no true fascial capsule.
The Sublingual gland is drained by approximately 10 small ducts
(the Ducts of Rivinus), which exit the superior aspect of the
gland and open along the Sublingual fold on the floor of
mouth.
Occasionally, several of the more anterior ducts may join to form
a common duct (Bartholin’s duct), which typically empties
into Wharton’s duct.

20. Sublingual Gland

21. Minor Salivary Glands
The minor salivary glands lack a branching network of draining
ducts. Instead, each salivary unit has its own simple duct.
The minor salivary glands are concentrated in the Buccal, Labial,
Palatal, and Lingual regions. In addition, minor salivary glands may
be found at the superior pole of the tonsils (Weber’s glands), the
tonsillar pillars, the base of tongue (von Ebner’s glands),
paranasal sinuses, larynx, trachea, and bronchi.
The most common tumor sites derived from the minor salivary
glands are the palate, upper lip, and cheek.

22. Microanatomy of the Salivary Glands
The secretory unit (salivary unit) consists of the acinus, myoepithelial
cells, the intercalated duct, the striated duct, and the excretory duct.
All salivary acinar cells contain secretory granules; in serous glands,
these granules contain amylase, and in mucous glands, these granules
contain mucin
Myoepithelial cells send numerous processes around the acini and
proximal ductal system (intercalated duct), moving secretions toward
the excretory duct.
The lumen of the acinus is continuous with the ductal system, made
up of (from proximal to distal) the intercalated duct, the striated duct,
and the excretory duct.
The intercalated duct is lined by low cuboidal epithelial cells.
The striated duct is lined by simple cuboidal epithelial cells proximally
Excretory ducts are lined by simple cuboidal epithelium proximally and
stratified cuboidal or pseudostratified columnar epithelium distally.

24. Serous acini & mucous tubules

25. The sublingual glands are another tubuloacinar gland, but in this case mucous cells
predominate. Acini are composed of both serous and mucous cells with the serous
cells mostly displaced to the terminal portion of the acini as outpocketings. They
appear as darkly staining crescents of cells (serous demilunes) around the ends of
mucous tubules

30. Function of Saliva
1) Moistens oral mucosa.
2) Moistens dry food and cools hot food.
3) Provides a medium for dissolved foods to stimulate the taste buds.
4) Buffers oral cavity contents. Saliva has a high concentration of bicarbonate ions.
5) Digestion. Alpha-amylase, contained in saliva, breaks 1-4 glycoside bonds, while lingual lipase
helps break down fats.
6) Controls bacterial flora of the oral cavity.
7) Mineralization of new teeth and repair of precarious enamel lesions. Saliva is high in calcium
and phosphate.
8) Protects the teeth by forming a “Protective Pellicle”. This signifies a saliva protein coat on the
teeth which contains antibacterial compounds. Thus, problems with the salivary glands
generally result in rampant dental caries.

31. Pseudoparotomegaly
1- Hypertrophy of the masseter ( young women ).
2- Aging ( absorption of adipose tissue & salivary glands
become more obvious ) .
3- Dental causes ( dental infection spreads to lymph nodes
within parotid or submandibular ) .

32. 4- Tumors in parapharyngeal space
- Chemodectoma .
- Glomus vagal tumors .
- Schwanoma of vagus .
- Schwanoma of sympathetic trunk .
- Enlarged lymph nodes .
-T.B.
- Metastatic.
Tumour → displace parotid or
submandibular gland .

33. 5- Tumors of Infratemporal fossa
- Haemangioma .
- Haemangiosarcoma .
- Leimyosarcoma .
- Hydatid cyst .
- Liposarcoma .
- Metastatic lymph node(s) .
- Tumour extend through mandibular notch or under
zygomatic arch .

34. 6- Mandibular tumors
osteosarcoma
chondrosarcoma
- ramus , mimic
parotid enlargement.
- body, mimic submandibular enlargement

35. 7- mastoiditis
Mastoiditis → subperiosteal abscess → dains into
→sternomastoid muscle or digastric muscle → lifting tail of
parotid .

36. 8- Intraparotid lesions
- facial n. neuroma .
- temporal a. aneurysms .
- enlarged lymph nodes : infection , metastatic .
- parotid cycts .

37. Metabolic Parotomegaly
- gout .
- Cushing's disease .
- myxedema .
-D.M.

38. Non Neoplastic Salivary Gland Disorders
• Reactive conditions
- Sialectasisand ranulas
• mucoceles .
• irradiation reactions
- Sjogren syndrome .
• sialolithiasis
- Salivary gland cysts .
• necrotizing . . .sialometaplasia
- Salivary fistulae .
• Infectious
• Nutrition disorders
• Medication reactions
• Immunologic disorders

39. Mucoceles of salivary glands
Mucoceles
- Most common reactive condition of
the minor salivary glands
- Mucoceles form when trauma to
excretory ducts of the minor glands
allows the spillage of mucus into the
surrounding connective tissue
- formation of painless, smooth surfaced,
bluish lesions

40. mucoceles
The lower lip is the most
frequent site followed by the
buccal mucosa , the ventral
surface of the tongue, the floor
of the mouth, and the
retromolar region .
Treatment:
• observation
• surgical excision .

41. Ranulas
Ranulas
- The result of blocked sublingual gland
ducts .
- Ranulas are unilateral, soft-tissue lesions,
often with a bluish appearance.
- They vary in size and may cross the
midline of the mouth and cause deviation
of the tongue
- A mucosal extravasation that herniates
the mylohyoid muscle is called a
"plunging" ranula

42. Treatment of ranula
Treatment of a Ranula
Surgical excision of the involved gland
and marsupialization
Marsupialization: suturing its walls to
an adjacent structure, leaving the
packed cavity to close by granulation

43. Irradiation Reaction
- A common side effect of tumoricidal
doses of ionizing radiation is xerostomia
- Frequent sips of water and frequent mouth
care are the most effective interventions
for xerostomia
- Saliva substitutes (e.g., mixed solutions of
methylcellulose, glycerin, and saline) or
pilocarpine hydrochloride may help these
symptoms

44. Sialectasis
Pathogenesis : -
The epithelial debris within salivary gland lead
to formation of a stone which blockades the
salivary gland duct , causing swell up of the
gland & if persists for some days , infection &
abscess formation will occur .

45. Sialectasis - Clinical picture
- History : - painful swelling of the gland during meal .
- Examination : -
1- Submandibular gland ;
stone in the duct can be palpated or seen .
2- parotid gland :
the mout of the duct is oedamatous &
pouting .
Drainage of saliva from the duct can be seen
when massage the gland .

46. Sialectasis - Investigations
1- Plain radiograph : radio opaque stone .
2- Sialogram : normal .
Overfilled
Obstruced duct
Sialectasis ; cystic , globular or
saccular

47. Plain radiograph shows radio opaque stone

48. salivary stones
80 % occur in the submandibular gland
10 % occur in the parotid gland
7 % occur in the sublingual gland
80 % of submandibular stones are radio opaque
Most parotid stones are radiolucent

49. Stone in Wharton’s duct

50. If partial obstruction occurs swelling may be mild
with chronic painful enlargement of the gland

52. If diagnostic doubt then stone can be
demonstrated by sialogram

53. Sialectasis- treatment
1- No treatment .
2- Peroral removal of a calculus .
3- Marsupialization of the duct .
4- Ligation of duct ( dismissed ) .
5- Duct dilatation ( dismissed ) .
6- Tympanic neurectomy .
7- Removal of submandibular gland .
8- Total parotidectomy .

54. Treatment is by either removal of stone from duct or
excision of the gland

55. Necrotizing Sialometaplasia
- Usually involves minor salivary glands -
- Occurs secondary to vascular infarct due to -
• smoking, trauma, DM, vascular disease,
- Age range 23-66 yrs
- 1-4 cm ulceration
- resembles mucoepidermoid carcinoma
and SCCA clinically and histologically
- Usually heal in 6-10 weeks-

56. Nutrition Disorders
Nutrition disorders such as pellagra (ie,
niacin deficiency), kwashiorkor (ie, protein
deficiency), beriberi (i.e, thiamine
deficiency), and vitamin A deficiency are
associated with parotid gland enlargement
Malabsorption syndromes (e.g., parasitic
and protozoan infections, amebic
dysentery, celiac sprue) also can cause
malnutrition and result in salivary gland dysfunction
Obesity & parotid ( excessive ingestion of starch ) .

57. Medication Reactions
Many medications
(e.g., amitriptyline ,Imipramine , nortriptyline
,atropine,dextropropoxyphene,phenothiazinederivati
ves , ↑ oestrogen oral contraceptive pills ,
antihistamines) decrease salivary flow and cause
parotid enlargement .

58. Metabolic Conditions
Patients with alcoholic cirrhosis often
experience asymptomatic enlargements of
their parotid glands, which are attributed
to chronic protein deficiency
Diabetes mellitus and hyperlipidemia
cause fatty infiltrations that replace the
functional parenchyma of the salivary
glands and decrease the flow of saliva

59. Parotitis
Pathgenesis :
Acute :- viral , bacterial , fungal .
Chronic :- T. B.
- sarcoid .
- actinomycosis .
- leprosy .
- tularaemia .

60. Parotitis
- clinical picture & diagnosis :-
• 1- severe pain made worse by eating .
• 2- high temperature .
• 3- acute worsening of pain if patient sips a little
lemon juice .

61. Parotitis - investigations
- Lab. Investigations :
WBC , E.S.R., viral titers , bacteriology .
- Radiological investigations :
1- plain radiographs .
2- sialography .
3- scanning .

62. Parotitis - treatment
- conservative :
1- oral hygiene .
2- analgesic .
3- antibiotic .
- Surgical treatment :
1- drain abscess .
2- peroral stone removal of duct
.

63. Immunologic conditions
HIV may manifest with parotid gland
enlargement and parotid
lymphadenopathy often are observed in
these immunocompromised patients.
Parotid gland enlargement may be caused
by benign lymphoepithelial lesions in the
gland, hypertrophied periparotid lymph
nodes, or secondary infections from CMV

64. Sjogren ‘s Syndrome
_ Clssification : -
1- Primary Sjogren Syndrome : xerostomia ,
xerophthalmia .
2- Secondary Sjogren syndrome : xerostomia ,
xerophthalmia , c. t. disease .
3- Benin lymphoepithelial lesion ( parotid gland )
.
4- Aggressive lymphocytic behaviour ( parotid
gland )

65. Sjogren ‘s Syndrome
- Clinical picture : -
1- EYE : redness , itching , photosensetivity , inability to
tolerate contact lenses .
2- Ear : S . O . M .
3- Nose : N. crustation , epistaxis .
4- Mouth : glazing oral mucosa .
5- Nasopharynx : sticky secretion .
6- Salivary gland : enlargement .
7- Larynx : laryngitis sicca .

66. Sjogren ‘s Syndrome
8- G. I. T. : disorder of oesophagus motility .
Achlorhydria .
1ry biliary cirrhosis .
Ch. Hepatitis .
9- Endocrine : thyroiditis , pancreatitis .
10- blood ; cryglobulinaemia ,
hypergammaglobulinaemic purpra .
11- Vascular : vasculitis .
12- Others : polyarthritis , chronic graft versus host
disease .

67. xerophthalmia

68. Primary Sjogren Syndrome :
xerostomia , xerophthalmia .

69. )salivary gland enlargement 30%)

70. Sjogren ‘s Syndrome
- Investigation : -
1- Blood : ↑↑ E.S.R., ↑↑ all Ig. Esp. IgG , + RH
factor , + A.N.A.
2- Specific immunological test : SSA & SSB antigens
.
3- Schirmer’s test : < 5 mm in 5 mins →
xerophalmia .
4- Examination of eye with Rose Bengal dye →
keratoconjunctivitis .

71. Sjogren ‘s Syndrome
5- Salivary flow rate : < 0.5 ml / min. → xerostomia .
6- Labial biopsy :
Grade 1 : slight lymphocytic infilteration .
Grade 2 : < 50 lymphocyte / mm
Grade 3 : 50 lymphocyte / mm
Grade 4 : > 50 lymphocyte / mm
6- Radiology : sialography → normal or abnormal
leakage of lipiodol into stroma of the gland .

72. labial or minor salivary gland biopsy

73. Axial FSEIR: Enlarged bilateral parotid glands
.with hypointense cystic-like changes

74. Axial T2W FSE: enlarged parotid glands containing T2
hyperintense globular collections of watery saliva

75. Sjogren ‘s Syndrome
Treatment : -
- steroids .
- immunosuppressive drugs .
- artificial tears , synthetic saliva .
- bromhexin 40 mg / day .
Follow up : lymphoma .

76. Salivary fistulae
- origin : - parotid .
- submandibular .
- Causes : - - surgery , facial trauma , sepsis .
- Treatment : -
1- prevention .
2- reduction of salivary production .
3- Excision of the fistulae .
4- Submandibular gland excision .
5- Parotidectomy .

77. Thank you

78. For communication
Dr, Ibrahim Habib Barakat .
M.D. ( Otorhinolaryngology )
E mail , salamatuall@yahoo.com.
salamatuall@hotmail.com .
www.facebook.com/Dr.Ibrahim.Barakat

79. Thank you