Disorders of Parotid Gland Prof. AMNA JAVED Surgical Unit-2 Learning Objectives • Classification of Parotid gland disorders • Infective Parotid gland swellings • Benign and malignant Tumors of Parotid gland • Parotid duct obstruction • Degenerative conditions of parotid gland • Methods of investigating parotid gland disorders and their Management • Disorders of the Parotid gland can be classified into, • Developmental disorders • Inflammatory disorders • Obstructive parotitis • Parotid gland tumours • Tumour like lesions • Degenerative conditions • Complication of parotid gland surgery Investigations • The initial imaging modality of choice is ultrasound • Ultrasound 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. • Developmental disorders • Developmental disorders such as agenesis, duct atresia and congenital fistula are extremely rare. Inflammatory disorders (Sialadenitis) • Viral infections • Bacterial infections • Human immunodeficiency virus-associated sialadenitis Viral infections • Mumps is the most common cause of acute painful parotid swelling and predominantly affects children. • Spread via airborne droplets of infected saliva. • Prodromal period of 1–2 days, during which the patient experiences fever, nausea and headache. • This is followed by pain and swelling in one or both parotid glands. • Pain is exacerbated by eating and drinking. • Symptoms resolve within 5–10 days. • 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. • Single episode of infection confers lifelong immunity. • Treatment of mumps is symptomatic with regular paracetamol and adequate oral fluid intake. • Complications include, ( more likely in adults) • Orchitis • Oophoritis • Pancreatitis • Sensorineural deafness • Meningoencephalitis • Viral agents that produce parotitis include Cox-sackie A and B, parainfluenza 1 and 3, Echo and lymphocytic choriomeningitis. • Atypical viral parotitis may present with predominantly unilateral swelling or submandibular involvement. Bacterial infections • Common in dehydrated elderly patients following major surgery OR associated with a salivary calculus. • Reduced salivary flow secondary to dehydration results in ascending infection via the parotid duct into the parotid parenchyma. • There is tender, painful parotid swelling that arises over several hours with generalized malaise, pyrexia and occasional cervical lymphadenopathy. • The pain is exacerbated by eating or drinking. • Intraoral examination may reveal pus exuding from the parotid gland papilla. • Most common causative organism is Staphylococcus aureus or Streptococcus viridans, and treatment is with appropriate intravenous antibiotics. • Sialography is contraindicated during acute infection. • Chronic bacterial sialadenitis is rare in the parotid gland. • There can be abscess formation • Gland becomes fluctuant and ultrasound may identify abscess within the gland that may require aspiration with a large-bore needle or formal drainage under general anaesthesia. In the latter procedure, the skin incision should be made low to avoid damage to the lower branch of the facial nerve. • A drain is inserted and left in situ for 24–72 hours. Recurrent parotitis of childhood • Unknown aetiology and variable prognosis. • Characterised by rapid swelling of one or both parotid glands associated with fever and malaise • Symptoms are made worse by chewing and eating. • The symptoms last from 3 to 7 days, and are then followed by a quiescent period of weeks to several months. • Children usually present between the ages of 3 and 6 years, • The diagnosis is based on the characteristic history • Confirmed dianosis by sialography showing characteristic punctate sialectasis likened to a ‘snowstorm’ • Responds well to regular endoscopic washouts and long courses of antibiotics. Human immunodeficiency virus-associated sialadenitis • Chronic parotitis in children may signify human immunodeficiency virus (HIV) infection. • Similar presentation to classical Sjögren’s syndrome in adulthood. • HIV-positive patients may also present with multiple parotid cysts, which cause gross parotid swelling and facial disfigurement. • CT and MRI demonstrate the characteristic ‘Swiss cheese’ appearance of multiple large cystic lesions • The swollen glands are usually painless and may regress on the institution of antiviral therapy. Cysts can be aspirated. Obstructive parotitis • There are several causes of obstructive parotitis, which produces intermittent painful swelling of the parotid gland, particularly at mealtimes. These include, • Stone formation • Strictures • Papillary obstruction Stone formation and strictures • Sialolithiasis is less common in the parotid gland (20%) than in the submandibular gland (80%). • Parotid duct stones are usually radiolucent and rarely visible on plain radiography. • The stones are easily demonstrated on ultrasound. • Small stones (~4mm) can be retrieved by baskets, slightly larger stones up to 8mm can be broken with lithotripsy and stones over 8mm diameter should be removed by endoscopic assisted surgery while preserving the gland. • Strictures are common in the parotid gland and are responsible for about 20% of obstructive cases. • Obstruction is due to mucus plugs which form after periods of stagnation. • Classically, the patient complains of a meal-time syndrome starting at breakfast and the saliva cannot seep past the mucus plug so the swelling persists. Massage eventually releases the plug with a gush of salty saliva. Infection is uncommon unless there is stone formation. • Strictures respond to dilatation and endoscopic washouts with steroid solutions. Papillary obstruction • Obstructive parotitis, can be caused by trauma to the parotid papilla. • The subsequent inflammation and oedema obstructs salivary flow, particularly at mealtimes. • The partial obstruction over a protracted period leads to dilation of the duct called ‘mega-duct’. A large dilated duct is visible coursing over the patient’s cheek. • Drainage has to be re-established. This can be done by progressive dilatation of the punctum and the insertion of a stent that is kept in position for many weeks. Surgical attempts to refashion the punctum are usually not successful. Tumours of the parotid gland • The parotid gland is the most common site for salivary tumour. • Most tumours arise in the superficial lobe and present as slow-growing, painless swellings below the ear in front of the ear or in the upper aspect of the neck. • Less commonly, tumours may arise from the accessory lobe and present as persistent swellings within the cheek. • Rarely, tumours may arise from the deep lobe of the gland and present as a parapharyngeal mass. Symptoms include difficulty in swallowing and snoring. Clinical examination reveals a diffuse firm swelling in the soft palate and tonsil. • Some 80–90% of tumours of the parotid gland are benign, the most common being pleomorphic adenoma • Malignant salivary gland tumours are divided into two distinct sub- groups: • Low-grade malignant tumours (e.g. acinic cell carcinoma) are indistinguishable on clinical examination from benign neoplasms. • High-grade malignant tumours usually present as rapidly growing, often painless swellings in and around the parotid gland. The tumour presents as either a discrete mass with infiltration into the overlying skin or a diffuse but hard swelling of the gland with no discrete mass. Presentation with advanced disease is common, and cervical lymph node metastases may be present. Benign tumour of the left parotid gland producing characteristic deflection of the ear lobe. Deep lobe tumour of the right parotid presenting with a swelling of the right soft palate. Magnetic resonance imaging scan revealing a large deep lobe tumour (arrow) of the right parotid gland, occupying the parapharyngeal space. Frey’s syndrome • Frey’s syndrome (gustatory sweating) is now considered an inevitable consequence of parotidectomy. • It results from damage to the autonomic innervation of the salivary gland with inappropriate regeneration of the postganglionic parasympathetic nerve fibres of the auriculotemporal nerve that aberrantly stimulate the sweat glands of the overlying skin. • The clinical features include sweating and erythema (flushing) over the region of surgical excision of the parotid gland as a consequence of autonomic stimulation of salivation by the smell or taste of food. The symptoms are entirely variable and are clinically demonstrated by a starch iodine test. • The management of Frey’s syndrome involves the prevention as well as the management of established symptoms. • PREVENTION • The incidence of Frey’s syndrome is minimal when extracapsular dissection is performed as the parotid fascia is primarily repaired and communication between exposed parotid parenchyma and subcutis sealed off. • MANAGEMENT • methods of managing Frey’s syndrome include: • Antiperspirants , usually containing aluminium chloride; • Denervation by tympanic neurectomy; • The injection of botulinum toxin into the affected skin. Granulomatous sialadenitis • Group of rare conditions that affect the salivary glands producing painless swellings of the parotid and/or