DISORDERS OF SALIVARY GLANDS.pptx
- 2. ANATOMY • Two parotid glands • Two submandibular glands • Two sublingual glands • Approximately ~800 minor salivary glands • The mucosa of the oral cavity contains approximately 800 minor salivary glands. They are distributed in the mucosa of the lips, cheeks, palate, floor of the mouth and retromolar area. These minor salivary glands also appear in other areas of the upper aerodigestive tract including the oropharynx, larynx and trachea as well as the sinuses. They have a histological structure similar to that of mucus-secreting major salivary glands. Overall, they contribute to 10% of the total salivary volume.
- 3. ANATOMY OF PAROTID GLAND • Parotid gland is present on the lateral aspect of the face, divided by the facial nerve into superficial lobe and deep lobe. Superficial lobe overlies the masseter and the mandible. Deep lobe is wedged between the mastoid process and the styloid process, ramus of the mandible and medial pterygoid muscle. • The duct of parotid, Stensen's duct ,opens in the mucosa of the cheek opposite the upper 2nd molar tooth. Parotid gland is covered by a true capsule which is a condensation of fibrous stroma of the gland and a false
- 4. ANATOMY OF SUBMANDIBULAR SALIVARY GLAND • Submandibular salivary gland is located in the submandibular triangle. It lies partly below and partly above the mandible. • It is in very close contact with the belly of the digastric muscle. • Submandibular salivary gland is divided into a superficial and a deep part by the mylohyoid muscle. • Main duct of submandibular gland, Wharton's duct
- 5. DISORDERS OF PAROTID GLAND 1)Developmental disorders • Developmental disorders such as agenesis, duct atresia and congenital fistula are extremely rare. 2) Inflammatory disorders Viral infections Bacterial infections Recurrent parotitis of childhood Human immunodeficiency virus-associated sialadenitis
- 6. • 3) Obstructive parotitis • Stone formation and strictures • Papillary obstruction
- 7. VIRAL INFECTIONS- • Mumps is the most common cause of acute painful parotid swelling and predominantly affects children. • It is spread via airborne droplets of infected saliva. • a prodromal period of 1–2 days, • fever, nausea and headache. followed by pain and swelling in one or both parotid glands. • Parotid pain can be very severe and exacerbated by eating and drinking. Symptoms resolve within 5–10 days..
- 8. • The diagnosis is based on history and clinical examination; recent contact with an infected patient with a painful parotid swelling is often sufficient to lead to a diagnosis • Treatment of mumps is symptomatic with regular paracetamol and adequate oral fluid intake. Complications of orchitis, oophoritis, pancreatitis, sensorineural deafness and meningoencephalitis are rare, but are more likely to occur in adults.
- 9. BACTERIAL INFECTIONS- • The patient presents with a tender, painful parotid swelling that arises over several hours . • There is generalised malaise, pyrexia and occasional cervical lymphadenopathy. • The pain is exacerbated by eating or drinking. • The parotid swelling may be diffuse, but often localises to the lower pole of the gland. • Intraoral examination may reveal pus exuding from the parotid gland papilla. The infecting organism is usually Staphylococcus aureus or Streptococcus viridans, and treatment is with appropriate intravenous antibiotics.
- 10. OBSTRUCTIVE PAROTITIS- • Sialolithiasis is less common in the parotid gland (20%) than in the submandibular gland (80%). • Parotid duct stones are usually radiolucent • located at the confluence of the collecting ducts. • The stones are easily demonstrated on ultrasound. • Small stones (~4 mm) can be retrieved by baskets, slightly larger stones up to 8 mm can be broken with lithotripsy and stones over 8 mm diameter should be removed by endoscopic assisted surgery while preserving the gland.
- 11. PAPILLARY OBSTRUCTION- • caused by trauma to the parotid papilla. • inflammation and oedema obstructs salivary flow. • The partial obstruction over a protracted period leads to dilation of the duct and an entity called ‘mega-duct’. A large dilated duct is visible coursing over the patient’s cheek. • Drainage has to be re-established by progressive dilatation of the punctum and the insertion of a stent • Papillotomy should not be performed ,leads to stricture formation and a life time of problems.
- 12. TUMORS OF THE PAROTID GLAND- • Low-grade malignant tumours (e.g. acinic cell carcinoma) are indistinguishable on clinical examination from benign neoplasm • High-grade malignant tumours usually present as rapidly growing, often painless swellings in and around the parotid gland.Among primary parotid malignant tumours, mucoepidermoid carcinoma is the most common, followed by adenocystic carcinoma
- 14. • Benign tumour of the left parotid gland producing characteristic deflection of the ear lobe
- 15. CLINICAL FEATURES OF PLEOMORPHIC ADENOMA - • Middle-aged women, around 40 years, are commonly affected (female, fifth decade and fullness near ear lobule). • Any painless swelling near the ear is best assumed to be parotid gland neoplasm unless proved otherwise. • Signs 1. Parotid swelling has the following classical features: • It presents as a swelling in front, below and behind ear. • Raises ear lobule. • Retromandibular groove is obliterated.
- 16. 2. It is rubbery or firm. Soft areas indicate necrosis. In longstanding cases, it can be hard. Surface can be nodular or sometimes bosselated. Skin is stretched and shiny. 3.Transformation into malignancy should be suspected when • growing rapidly • Skin infiltration occurs • Facial nerve paralysis occurs • Gets fixed to masseter muscle • Red, dilated veins over the surface • Presence of lymph nodes in the neck • Tumor feels stony hard
- 17. INVESTIGATIONS • The initial imaging modality of choice is ultrasound as it demonstrates if the lump is intrinsic to the parotid or not. It also facilitates accurate sampling of the lesion by FNAC or True-Cut biopsy. Subsequently, CT and MRI are the most useful imaging techniques . • Open surgical biopsy is contraindicated unless evidence of gross malignancy is present, and preoperative histological diagnosis is required as a prelude to radical parotidectomy
- 18. Magnetic resonance imaging scan revealing a space-occupying lesion (arrow) in the right parotid gland
- 19. TREATMENT • The aim of superficial parotidectomy is to remove the tumour with a cuff of normal surrounding tissue. The most important structure traversing the parotid gland in the facial nerve. • Parotid tumour excision techniques are classified based on the approach onto the facial nerve. Essentially the traditional parotidectomy is in reality a dissection of the facial nerve. • A parotidectomy is conservative when the nerve is spared and radical when the nerve is excised en bloc with the tumour. • A superficial parotidectomy is when the part of the gland superficial to the facial nerve is removed. A deep lobe parotidectomy is when the part of the gland beneath the nerve is removed and total parotidectomy is when both are dissected and removed. Superficial parotidectomy can be partial in relatively small tumours that are removed with a cuff of clinically normal parenchyma without removal of the entire superficial portion of the gland.
- 20. • An alternative surgical approach is to focus on the tumour itself as the principal procedure and not facial nerve dissection. Extracapsular dissection is now an established alternative to parotidectomy. It does not require formal facial nerve dissection and is a less invasive technique with reduced morbidity. Temporary facial nerve injury rates are 7% compared with 25% for superficial parotidectomy. • Radical parotidectomy is performed for patients in whom there is clear histological evidence of a high-grade malignant tumour (e.g. squamous cell carcinoma) with invasion of facial nerve. Low-grade and low stage malignant tumours can usually be managed by standard superficial parotidectomy.
- 21. • Radical parotidectomy involves removal of all parotid gland tissue and elective division of the facial nerve, usually through the main trunk. • The surgery inevitably removes the ipsilateral masseter muscle and may also require simultaneous neck dissection, particularly where there is clinical, radiological and cytological evidence of lymph node metastases in the ipsilateral neck. • When indicated, facial nerve can be repaired using cable grafts (interpositional greater auricular or sural nerve grafts).
- 22. COMPLICATIONS OF PAROTID GLAND SURGERY • Complications of parotid gland surgery include- • haematoma formation • infection • deformity: unsightly scar and retromandibular hollowing; temporary facial nerve weakness; • transection of the facial nerve and permanent facial weakness; • sialocele; facial numbness; • permanent numbness of the ear lobe associated with great auricular nerve transection; • Frey’s syndrome.
- 23. DISORDERS OF SUBMANDIBULAR GLAND 1.Ectopic/aberrant salivary gland tissue- • The most common ectopic salivary tissue is a Stafne bone cyst, the origin of which is uncertain. It presents as an asymptomatic, clearly demarcated radiolucency of the angle of the mandible, characteristically below the inferior dental neurovascular bundle. No treatment is required
- 24. 2.Inflammatory disorders of the submandibular gland- Acute submandibular sialadenitis a)Viral. The paramyxovirus (mumps) is a viral illness of the salivary glands that usually produces parotitis. The submandibular glands are occasionally involved, causing painful tender swollen glands. Other viral infections of the submandibular gland are extremely rare. b)Bacterial. Bacterial sialadenitis is more common than viral sialadenitis and occurs secondary to obstruction by stone. These stones can be reliably removed by minimally invasive techniques that preserve the gland. Chronic submandibular sialadenitis.
- 25. 3.Obstruction and trauma- • The most common cause of obstruction within the submandibular gland is stone formation (sialolithiasis) within the gland and its associated duct system. • Eighty per cent of all salivary stones occur in the submandibular glands because their secretions are relatively viscous. • Eighty per cent of submandibular stones are radio-opaque and can be identified on plain radiography . • Stones are mainly composed of phosphate and oxalate salts. • The second most common cause of submandibular duct obstruction is stricture.
- 26. • Clinical symptoms- Patients usually present with acute painful swelling in the region of the submandibular gland, precipitated by eating . The swelling occurs rapidly and often resolves spontaneously over 1–2 hours after the meal is completed (meal-time syndrome). Clinical examination reveals an enlarged firm submandibular gland, tender on bimanual examination. Pus may be visible draining from the sublingual papilla or expressed by bimanual palpation of the gland
- 27. Lower occlusal X-ray highlighting a radio-opaque submandibular duct stone (arrowhead). Note the larger stone posteriorly located in the hilum of the gland (arrow).
- 28. • Small (less then 4 mm) mobile stones can be retrieved using a Dormia® basket. • For larger stones, extracorporeal or intracorporeal lithotripsy can be employed to break the stone into smaller pieces using shock waves and the stone fragments can then removed with a basket. • Submandibular gland incision is indicated for: • sialadenitis, when minimally invasive methods have failed; • salivary tumours.
- 29. COMMON DISORDERS OF THE SUBLINGUAL GLANDS Cysts- • The term ‘ranula’ is applied to a mucous extravasation cyst that arises from the sublingual gland. It produces a characteristic translucent swelling that takes on the appearance of a ‘frog’s belly’ (ranula). • A ranula can resolve spontaneously, but many also require active treatment. The traditional and effective way is to remove the sublingual gland. • New less invasive techniques are now quite effective (85% success) in resolving ranulas while preserving the gland. Incision and drainage, however tempting, usually results in recurrence.
- 30. Large ranula affecting the floor of the mouth.
- 31. Plunging ranula • is a rare form of mucous retention cyst that arises from the sublingual salivary glands. • .Patients present with a dumbbell-shaped swelling that is soft, fluctuant and painless in the submandibular or submental region of the neck. • Diagnosis is made on ultrasound or magnetic resonance imaging (MRI) examination but clinched by aspirating thick yellow treacly fluid from the cyst.
- 32. Plunging ranula in the left submandibular region
- 33. LONG QUESTIONS- • 1)Describe surgical anatomy of submandibular gland. Discuss management of submandibular sialadenitis? • 2)Classify salivary gland tumors.Discuss management of pleomorphic adenoma?
- 34. MCQ 1. Commonest tumour of minor salivary gland is: A. Pleomorphic adenoma B. Warthim 's tumour C. Malignant tumour D. Mucoepidermoid tumour
- 35. 2. Parotid duct opens opposite: A. Upper canine tooth B. Lower canine tooth C. Upper 2nd molar tooth D. Lower 2nd molar tooth
- 36. 3.Chronic parotitis in children is pathognomonic of which infection? A. HCV infection B. HBV infection C. HIV infection D. Syphilis
- 37. 4. Which is the common site of calculi in submandibular salivary gland? A. Superficial lobe B. Deep lobe C. Accessory lobe D. Duct
- 38. 5. Deep lobe tumours of parotid presents as following features except: A. Dysphagia B. Can push tonsils C. Can push soft palate D. Can block the external auditory meatus
- 39. 6.The investigation of choice in deep lobe tumours of parotid gland is: A. CT scan B. Angiography C.MRI D. Ultrasound
- 40. 7. Conley's pointer refers to: A. Location of facial nerve in relation to tragal cartilage B. Location of facial nerve in relation to posterior belly of diagstric C Location of facial nerve in relation to retromandibular vein D. Location of facial nerve in relation to pinna
- 41. 8. Following are true for chronic hyperplastic candidiasis except: A. Invasion of Candida albicans B. Antifungal treatment helps C. High malignant potential D. Floor of the mouth is affected
- 42. 9. Following benign tumours have high incidence of recurrence except? A. Adamantinoma B. Deep lobe tumours of parotid gland C. Desmoid tumours D. Diffuse lipoma
- 43. 10. Recommended treatment of pleomorphic adenoma is: A. Enucleation B. Excision C. Superficial parotidectomy D. Wide excision