1. The major salivary glands are the parotid, submandibular, and sublingual glands. The parotid gland is the largest and lies below the ear.
2. Common diseases of the parotid gland include acute suppurative parotitis caused by bacterial infection, and pleomorphic adenoma which is the most common benign tumor.
3. The submandibular gland lies under the jaw and drains via Wharton's duct into the mouth. Diseases include sialadenitis from duct obstruction and rare tumors.
4. Minor salivary gland diseases include ranulas and tumors which often present in the palate and are frequently malignant.
2. Anatomy 3 major salivary glands: The parotid glands The submandibular glands The sublingual glands Many minor salivary glands in mucosa of cheeks, lips, palate.
3. Parotid gland Largest salivary gland Lies b/w sternomastoid and mandible below the EAM Coverings : True capsule False capsule – a layer from the deep cervical fascia
4. Lobes of parotid gland Parotid divided into superficial and deep lobes by the facial nerve Fasciovenous plane of Patey
5.
6.
7. Structures within the parotid gland 1. External carotid artery : Gives terminal branches in the gland Maxillary artery and superficial temporal artery. 2. Retromandibular vein Formed by union of sup. Temporal and maxillary vein Joins post. Auricular vein to form the external jugular vein.
8. Structures within the parotid gland 3. The facial nerve Enters upper part of posteromedial border Passes forward and downward and divides into Temporal br. Temporofacial Zygomatic br. Main trunk Buccal branches Cervicofacial Marginal mandibular br. Cervial br.
10. Parotid duct Stensen’s duct 5cm in length Comes out through anterior surface of glands. Peircesbuccinator and opens in buccal mucosa opposite crown of second upper molar tooth.
12. Acute suppurativeparotitis Causative organisms : Staph. aureus, streptococcus viridans, pneumococci commonly. Route : usually from stensen’s duct, rarely blood born Predisposing factors : Dehydrated patients Obstructed duct
13. Clinical features Pain and swelling on the side of face BRAWNY edematous swelling over parotid region with all signs of inflamation Fever If pressed pus may be seen coming from the opening of stensen’s duct.
14. Treatment Improve general condition. Improve oral hygeine. Soft diet as chewing is painful. Antibiotics. If no response incision and drainage : Vertical incision on skin but transverse incision on the parotid fascia to safeguard facial nerve and branches
15. Acute parotitis Usually due to viral parotitis. Rarely in association with tuberculosis, actinomycosis and cat scratch disease. MUMPS – commonest cause Non suppurative Initially unilateral but proceeds to bilateral affection.
16. Recurrent subacute and chronic parotitis If on both sides, suspect Sjogren’s syndrome. Other causes : calculus, autoimmune Recurrent attacks of pain and swelling. Gland progressively replaced by fibrous tissue.
17. Management Investigation : sialography Treatment Control infection by antibiotics. Remove stone Dilate the duct if it is constricted Total conservative parotidectomy if all above measures fail
18. Neoplasms of the salivary gland 75% occur in the parotid glands. In parotid glands, 80% of tumors are benign. Of these 80% are Pleomorphic adenomas. 15% of salivary tumors occur in submandibular glands. Of these 50% are benign and 50% and malignant. In carcinomas mucoepidermoid ca> adenoid cystic ca > adenocarcinoma
19. 10% of salivary tumors occur in sublingual and minor salivary glands 60-70% of these are malignant
24. Pleomorphic adenoma ‘Mixed tumor’ Commonest tumor of salivary glands. There is cartilage besides epithelial cells on histology. Sites : 90% Parotids 7% Submandibular gland 3% rest
25. Pathology Macro : rubbery, bosselated, on cut section, mucoid appearance with zones of cartilage. Micro : pleomorphicstroma with pseudocartilage, lymphoid, myxoid and fibrous elements besides epithelial cells.
26. Clinical features Age : any age but common around 40 yrs Sex : slightly more incidence in females. Painless swelling since years. Slow growth. Site : usually below the lobule of ear. Variable consistency : firm and rubbery
27.
28. Malignant transformation Malignant transformation may occur in 3% to 5% Signs of malignant transformation : Long duration (10-20yrs) Becomes painful Starts growing rapidly Becomes stony hard Facial nerve involvement L. node involvement. Jaw movement restriction.
29. Treatment The tumor is radioresistant. Excision is the treatment of choice. For diagnosis FNAC can be done but incisional biopsy is contraindicated. Superficial parotidectomy is the treatment of choice. Submandibular gland : submandibular gland excision.
30. Warthin’s tumor Represents 5-15% of parotid tumors. Occurs only in parotid. Almost always in lower portion of parotid gland.
31. Pathology Gross : soft and frequently cystic Micro : cores of papillary processes with abundant lymphoid tissue.
32. Clinical features Age : middle and old age Sex : much more common in males Painless slow growing tumor over angle of jaw May be bilateral Surface is smooth
33. Management FNAC Hot spot in 99mTC pertechnate scan Treatment : superficial parotidectomy
34. Mucoepidermoid carcinoma Slow growing Invade local tissues to a limited degree Occasionally metastasise to lymph nodes, lungs or skin. Clinically they are hard, become fixed when very large.
35. Acinic cell tumor Almost all occur in parotid gland Composed of cells resembling acini Women > Men Rare and slow growing Tend to be soft and occasionally cystic
36. Adenoid Cystic Carcinoma Consists of myoepithelial and duct epithelial cells Slow growing but more invasive than the above described malignant tumors Tumor is always more extensive than the physical or radiological appearance Minor glands > submandibular > parotid
37. Adenocarcinomas, Epidermoid ca & Undifferentiated Ca Resemble various glandular elements seen in salivary glands Divided according to predominant cell type Demonstrate fixation to adjacent bone, pain, anesthesia of skin and paralysis of muscles
38. In case of parotid gland, facial nerve irritability occurs first, later gives rise to facial paralysis Limitation of jaw movements
39. Submandibular gland Composed of superficial part and deep part Divided by mylohyoid muscle Superficial part lies in the submandibular triangle b/w 2 bellies of digastric muscle Deep part lies abv & deep to mylohyoid in the floor of mouth
40.
41. Submandibular duct (Wharton’s duct) About 5 cm long Runs fwd from the deep part of the gland to enter floor of the mouth Opens on a papilla beside the frenulum of the tongue
44. Sialography Radio opaque liquid like Hypaque (Sodium diatrizoate) Lipiodol Injected into duct system of the gland and radiograph taken Volume of 0.5-2ml used
45. Shows Obstruction, Dilatation & narrowing of duct Position and size of salivary neoplasm Extraglandular mass Fistula and abscess cavities
46.
47. Acute suppurativesialadenitis of submandibular gland Usually secondary to obstruction of Whartons duct Organism – S. aureus common Responds well to antibiotics and improved oral hygiene Rarely, I & D is required
48. Recurrent subacute and chronic sialoadenitis These inflamations are always secondary to obstruction or autoimmune disease. Recurrent attacks of pain and swelling Sialography confirms the diagnosis and gives a clue about the cause Treatment is of the primary condition
49.
50. Tumors of submandibular glands Tumors in this gland are uncommon Enlargement is more due to calculus Of all tumors, mixed tumor is most common Swelling is hard but not stony hard and should be differentiated from submandibular lymph node
51.
52. Obstruction of a major salivary gland duct Characteristic symptom : Recurrent painful swelling of the affected gland at mealtimes. First indication may be acute/ subacute infection
53. Causes of obstruction Salivary calculi Strictures of the duct wall Edema or fibrosis of the papilla Pressure on the duct Invasion of the duct by malignant neoplasm
54. Salivary calculi Submandibular calculi are most common Easily demonstrated on plain X ray Calculi within the duct removed via floor of mouth Calculi within the gland or chronic infection excision of the gland
55.
56.
57. Sublingual and minor salivary gland diseases Mucous cyst (retention cyst) : pink, soft swellings on inner surface of lips and cheeks Cyst and associated minor gland should be excised together Tumors : usually malignant palate > upper lip > rest Treatment : wide excision and grafting
58.
59. Ranula Extravasation cysts arising from a damaged sublingual duct Ranula = frog (latin) Transluscent bluish swelling in the floor of mouth with vessels running over it May flow over post margin of mylohyoid and present as a plunging ranula Rx : excision, marsupilization
60.
61.
62. Mikulicz’s disease Characterized by Enlargement of all salivary glands Enlargement of both lacrimal glands Dry mouth This occurs due to replacement of glandular tissue by lymphocytes Occurs b/w 20 and 40 yrs of age Thought to be autoimmune process
63. Sjogren’s syndrome All features of Mikulicz’s disease plus Dry eyes (Keratoconjuntivitissicca) Generalized arthritis
65. Frey’s syndrome Also called as auriculo-temporal syndrome Occurs due to damage to the autonomic innervation of the salivary gland Inappropriate regeneration of parasympathetic fibers Stimulation of sweat glands of overlying skin with stimulus of salivation
66. Causes : Surgery of the parotid gland Injury to parotid gland Clinical features : sweating and erythema at the site of parotid surgery by smell or taste of food.
67. Investigation : Starch iodine test : After painting the area with iodine Starch applied over the area becomes blue on gustatory stimulus.
68. Prevention Sternomastoid muscle flap Temporalisfascial flap Artificial membranes Form a barrier between skin and parotid bed to minimise inappropriate regeneration of autonomic nerve fibres.
69. Treatment Initially conservative management Most recover in 6 months Anti-perspirants Denervation by tympanic neurectomy Injection of botulinum toxin into the afected skin.
70. Parotidectomy Types : Superficial parotidectomy : superficial to facial nerve Total conservative parotidectomy : for benign diseases involving deep lobe. Facial nerve is preserved. Radical parotidectomy : For carcinomas Facial nerve, fat, facia, muscles and lymph nodes are removed. Later reconstruction using hypoglossal or greater auricular nerve.
73. Identificaton of facial nerve Conley’s pointer : inferior portion of cartilagnous canal. Facial nerve is 1cm deep and inferior to its tip. Upper border of posterior belly of the digastric muscle. Fascial nerve immediately superior to this. By nerve stimulator
74. How To Save The Facial Nerve During Parotid Salivary Gland Tumor Surgery.flv
76. Facial nerve injury(Lower motor neuron lesion) Causes Trauma Parotid surgery Compression of facial nerve(Bell’s nerve)
77. Clinical features Inability to close the eye lid Difficulty in blowing and clenching Drooping of the angle of mouth Obliteration of naso-labial fold
78. Treatment Usually temporary, recovers in 6 months Nerve grafting Suspension of angle of mouth to zygomatic bone Lateral tarsorrhaphy
79. Submandibular gland excision Indications : Chronic sialoadenitis Stone in submandbular gland Submandibular gland tumors
80. Incision Placed 2-4 cm below thmandie, parallel to it Preserve : Marginal mandibular nerve Lingual nerve Hypoglossal nerve