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47-417: It commences in the substance of the parotid gland , on a level with the angle of the mandible , and runs perpendicularly down the neck, in the direction of a line drawn from the angle of the mandible to the middle of the clavicle superficial to the sternocleidomastoideus . In its course it crosses the sternocleidomastoideus obliquely, and in the subclavian triangle perforates the deep fascia , and ends in

94-401: A fine-needle-like aspiration biopsy . With various benign lesions, most commonly the pleomorphic adenoma, there is a risk of developing malignancy over time. As a result, these lesions are typically resected. Pleomorphic adenoma is seen to be a common benign neoplasm of the salivary gland and has an overall incidence of 54–68%. The Warthin tumour has a lower incidence of 6–10%; this tumour

141-419: A last resort. Acute non-suppurative disease that often occurs in epidemics. Prevented by MMR vaccine . Caused by paramyxovirus that is transmitted by infected saliva and urine. A prodromal period of 24–28 hours is experienced, followed by rapid and painful swelling of the parotid gland. Treatment is supportive (bedrest, hydration) as spontaneous resolution occurs within 5–10 days. Diffuse gland enlargement

188-399: A superior end in the form of a small superior surface and an inferior end (apex). A number of different structures pass through the gland. From lateral to medial , these are: Sometimes accessory parotid glands are found as an anatomic variation . These are close to the main glands and consist of ectopic salivary gland tissue. Capsule of parotid gland A capsule of the parotid gland

235-446: Is a slowly enlarging gland, with diagnosis made by identification of the underlying systemic disorder and measurements of salivary chemical levels. Sodium and chloride ion levels will be elevated two or three times normal levels. Treatment is by addressing the underlying systemic condition. Sarcoidosis is a chronic systemic disease characterised by the production of non-caseating granulomas of unknown aetiology. It can affect any organ of

282-505: Is also provided with a false capsule by the investing layer of the deep cervical fascia. The fascia at the imaginary line between the angle of the mandible and the mastoid process splits into a superficial and a deep lamina to enclose the gland. The risorius is a small muscle embedded with this capsule substance. The gland has short, striated ducts and long, intercalated ducts. The intercalated ducts are also numerous and lined with cuboidal epithelial cells and have lumina larger than those of

329-454: Is associated with smoking and is more common in older men. Benign lesions of the parotid gland have a significantly higher incidence than malignant lesions. Malignant salivary gland lesions are rare. However, when a tumour extends to the submandibular , sublingual and the minor salivary glands, they tend to be malignant. Distinguishing a malignant lesion from a benign one may be difficult as they both present as painless lesions. A biopsy

376-569: Is crucial in aiding diagnosis. There are common signs that can highlight the presence of a malignant lesion. These include facial nerve weakness, rapid increase of the size of the lump as well as ulceration of the mucosa of the skin. Mucoepidermoid carcinoma is a common malignant tumour of the salivary glands and has a low incidence of 4–13%. Adenoid cystic carcinoma is also a common malignant salivary gland lesion and has an incidence of 4–8%. This carcinoma tends to invade nerves and can re-occur post-treatment. A developmental polycystic disease of

423-413: Is formed from the investing layer of the deep cervical fascia. It is supplied by the great auricular nerve. The fascia splits to enclose the gland. This splitting occurs between the angle of the mandible and the mastoid process. The superficial lamina (parotidomassetric fascia) is thick and is attached to the zygomatic arch. The deep lamina is thin and is attached to the styloid process, tympanic plate, and

470-410: Is more common in males than in females). Their importance is in relation to their anatomical position and tendency to grow over time. The tumorous growth can also change the consistency of the gland and cause facial pain on the involved side. Around 20% of parotid tumors are malignant, with the most common tumors being mucoepidermoid carcinoma and adenoid cystic carcinoma . Other malignant tumors of

517-447: Is provided with two pairs of valves, the lower pair being placed at its entrance into the subclavian vein, the upper in most cases about 4 cm above the clavicle. The portion of vein between the two sets of valves is often dilated, and is termed the sinus. These valves do not prevent the regurgitation of the blood, or the passage of injection from below upward. The external jugular vein varies in size, bearing an inverse proportion to

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564-429: Is seen, and may affect patients throughout all stages of the infection. Lymphoepithelial cysts seen via imaging help aid diagnosis. Pathogenic process occurs due to circulating CD8 lymphocytes within the salivary gland. Medical management via use of antiretrovirals , excellent oral hygiene measures and sialogogues. Most commonly seen in fourth and fifth decades in women, and can affect any salivary gland. Presentation

611-427: Is the first step in the decomposition of starches during mastication. It is the main exocrine gland to secrete this. It breaks down amylose (straight chain starch) and amylopectin (branched starch) by hydrolyzing alpha 1,4 bonds. Additionally, the alpha amylase has been suggested to prevent bacterial attachment to oral surfaces and to enable bacterial clearance from the mouth. The parotid salivary glands appear early in

658-419: Is the route that saliva takes from the major salivary gland , the parotid gland , into the mouth . It opens into the mouth opposite the second upper molar tooth . The parotid duct is formed when several interlobular ducts, the largest ducts inside the parotid gland , join. It emerges from the parotid gland. It runs forward along the lateral side of the masseter muscle for around 7 cm. In this course,

705-433: The parotid duct . Each gland lies behind the mandibular ramus and in front of the mastoid process of the temporal bone . The gland can be felt on either side, by feeling in front of each ear, along the cheek, and below the angle of the mandible . The parotid duct, a long excretory duct, emerges from the front of each gland, superficial to the masseter muscle . The duct pierces the buccinator muscle , then opens into

752-413: The subclavian vein lateral to or in front of the scalenus anterior , piercing the roof of the posterior triangle . It is separated from the sternocleidomastoideus by the investing layer of the deep cervical fascia, and is covered by the platysma , the superficial fascia, and the integument; it crosses the cutaneous cervical nerve, and its upper half runs parallel with the great auricular nerve . It

799-449: The acini. The striated ducts are also numerous and consist of simple columnar epithelium, having striations that represent the infolded basal cell membranes and mitochondria. Though the parotid gland is the largest, it provides only 25% of the total salivary volume. The serous cell predominates in the parotid, making the gland secrete a mainly serous secretory product. The parotid gland also secretes salivary alpha-amylase ( sAA ), which

846-418: The body, depressing cellular immunity and enhancing humoral immunity. Salivary gland involvement primarily involves both parotid glands, causing enlargement and swelling. Salivary gland biopsy with histopathologic examination is needed to make the distinction between whether Sjoren's syndrome or sarcoidosis is the cause of this. Parotid duct The parotid duct or Stensen duct is a salivary duct. It

893-434: The duct by salivary duct calculi or external compression. Parotid gland swellings can also be due to benign lymphoepithelial lesions caused by Mikulicz disease and Sjögren syndrome . Swelling of the parotid gland may also indicate the eating disorder bulimia nervosa , creating the look of a heavy jaw line. With the inflammation of mumps or obstruction of the ducts, increased levels of the salivary alpha amylase secreted by

940-422: The duct is surrounded by the buccal fat pad . It takes a steep turn at the border of the masseter and passes through the buccinator muscle , opening into the vestibule of the mouth , the region of the mouth between the cheek and the gums , at the parotid papilla, which lies across the second maxillary (upper) molar tooth . The exit of the parotid ducts can be felt as small bumps ( papillae ) on both sides of

987-412: The face and eventually becomes bilateral. The transmission of the paramyxovirus is by contact with the infected persons saliva. Initial symptoms tend to be a headache and fever. Mumps is not fatal, however further complications can include swelling of the ovaries or the testes. Diagnosis of mumps is confirmed through viral serology, management of the condition includes hydration and good oral hygiene of

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1034-400: The gland by passing along the external carotid artery and middle meningeal artery . They act to cause vasoconstriction. Parasympathetic Preganglionic parasympathetic fibers for the parotid gland arise in the brainstem in the inferior salivatory nucleus , and leave the brain in the glossopharyngeal nerve (CN IX) , then pass in the tympanic nerve to the tympanic plexus , then from

1081-477: The increased potential for postoperative relapse. Thus, detection of early stages of a parotid tumor is extremely important in terms of postoperative prognosis. Operative technique is laborious, because of relapses and incomplete previous treatment made in other border specialties. Surgical techniques in parotid surgery have evolved in the last years with the use of neuromonitoring of the facial nerve and have become safer and less invasive. After surgical removal of

1128-513: The junction of the subclavian vein and the internal jugular vein. The external jugular is a large vein used in prehospital medicine for venous access when the Paramedic is unable to find another peripheral vein It is commonly used in cardiac arrest or other situations where the patient is unresponsive due to the pain associated with the procedure. In a cardiac arrest using this vein has the advantage that

1175-480: The main duct, complete gland excision may be necessary. The parotid salivary gland can also be pierced and the facial nerve temporarily traumatized when an inferior alveolar local anesthesia nerve block is incorrectly administered, causing transient facial paralysis. About 80% of tumors of the parotid gland are benign. The most common of these include pleomorphic adenoma (70% of tumors, of which 60% occur in females ) and Warthin tumor (i.e. adenolymphoma , which

1222-501: The main parotid duct. The patient usually complains of intense pain when salivating and tends to avoid foods which produce this symptom. In addition, the parotid gland may become enlarged upon trying to eat. The pain can be reproduced in clinic by squirting lemon juice into the mouth. Surgery depends upon the site of the stone: if within the anterior aspect of the duct, a simple incision into the buccal mucosa with sphinterotomy may allow removal; however, if situated more posteriorly within

1269-406: The main parotid glands. The word parotid literally means " beside the ear ". From Greek παρωτίς (stem παρωτιδ-) : (gland) behind the ear < παρά - pará : in front, and οὖς - ous (stem ὠτ-, ōt-) : ear. The parotid glands are a pair of mainly serous salivary glands located below and in front of each ear canal , draining their secretions into the vestibule of the mouth through

1316-431: The mouth on the inner surface of the cheek, usually opposite the maxillary second molar . The parotid papilla is a small elevation of tissue that marks the opening of the parotid duct on the inner surface of the cheek. The gland has four surfaces – superficial or lateral, superior, anteromedial, and posteromedial. The gland has three borders – anterior, medial, and posterior. The parotid gland has two ends –

1363-401: The mouth that usually positioned next to the maxillary second molar . The buccinator acts as a valve that prevents air forcing into the duct, which would cause pneumoparotitis . The parotid duct lies close to the buccal branch of the facial nerve (VII). It is also close to the transverse facial artery . Running along with the duct superiorly is the transverse facial artery , and

1410-423: The other veins of the neck, it is occasionally double. This vein receives the occipital occasionally, the posterior external jugular , and, near its termination, the transverse cervical , transverse scapular , and anterior jugular veins ; in the substance of the parotid , a large branch of communication from the internal jugular joins it. The external jugular vein drains into the subclavian vein lateral to

1457-448: The otic placodes of the ears and branch to form solid cords with rounded terminal ends near the developing facial nerve. Later, at around 10 weeks of prenatal development, these cords are canalized and form ducts, with the largest becoming the parotid duct for the parotid gland. The rounded terminal ends of the cords form the acini of the glands. Secretion by the parotid glands via the parotid duct begins at about 18 weeks of gestation. Again,

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1504-515: The paramedic can stay at the head and intubate the patient as well. Although many EMTs and paramedics use this vein, the American Heart Association still recommends the use of the cephalic vein . [REDACTED] This article incorporates text in the public domain from page 646 of the 20th edition of Gray's Anatomy (1918) Parotid gland The parotid gland is a major salivary gland in many animals. In humans,

1551-495: The parotid gland ( parotidectomy ), the auriculotemporal nerve is liable to damage and upon recovery it fuses with sweat glands. This can cause sweating on the cheek on the side of the face of the affected gland. This condition is known as Frey's syndrome . Commonly caused by a retrograde bacterial infection as a result of illness, sepsis , trauma, surgery, reduced salivary flow due to medications, diabetes , malnutrition and dehydration. Classically symptoms of painful swelling in

1598-411: The parotid gland can be detected in the blood stream. Mumps is seen to be a common cause of parotid gland swelling – 85% of cases occur in children younger than 15 years. The disease is highly contagious and spreads by airborne droplets from salivary, nasal, and urinary secretions. Symptoms include oedema in the area, trismus as well as otalgia. The lesion tends to begin on one side of

1645-399: The parotid gland include acinic cell carcinoma, carcinoma expleomorphic adenoma, adenocarcinoma (arising from ductal epithelium of parotid gland), squamous cell carcinoma (arising from parenchyma of parotid gland), and undifferentiated carcinoma. Metastasis from other sites like phyllodes tumour of breast presenting as parotid swelling have also been described. Critically, the relationship of

1692-400: The parotid gland without innervating the gland itself. Arterial supply The external carotid artery and its terminal branches within the gland, namely, the superficial temporal and the maxillary artery, also the posterior auricular artery supply the parotid gland. Venous drainage Venous return is to the retromandibular veins. Lymphatic drainage The gland is mainly drained into

1739-542: The parotid region when eating seen. Management is based upon antibacterials, rehydration combined with gentle massage to encourage salivary flow. A latent infection despite clinical resolution of the disease resulting in impaired function. Histologically glandular duct dilation, abscess formation and atrophy may be seen. Parotid secretions are viscous. Disease course shows pain and swelling, waxing and waning. Radiographic screening should be undertaken to rule out sialolith . Management with palliative care with parotidectomy as

1786-414: The patient requiring excellent motivation. However, since the development of the mumps vaccine, given at the age of between 4–6 years, the incidence of this viral infection has greatly reduced. This vaccine has reduced the incidence by 99%. Tuberculosis and syphilis can cause granuloma formation in the parotid glands. Salivary stones mainly occur within the main confluence of the ducts and within

1833-408: The preauricular or parotid lymph nodes which ultimately drain to the deep cervical chain. The parotid gland receives both sensory and autonomic innervation. Sympathetic The cell bodies of the preganglionic sympathetic fibres that supply the gland usually lie in the lateral horns of upper thoracic spinal segments (T1-T3). Postganglionic sympathetic fibers from superior cervical ganglion reach

1880-426: The ramus of the mandible. The part of the deep lamina extending between the styloid process and the mandible is thickened to form a stylomastoid ligament. The stylomandibular ligament separates the parotid gland from the superficial lobe of the submandibular gland. The facial nerve (CN VII) splits into its branches within the parotid gland, thus forming its parotid plexus . Nerves of this plexus then pass through

1927-414: The salivary gland is seen to be extremely rare and is seen to be independent of recurrent parotitis . The cause is thought to be a defect in the interactions between activin , follistatin and TGF-β , leading to a developmental disorder of glandular tissue. Surgical treatment of parotid gland tumors is sometimes difficult because of the anatomical relations of the facial nerve parotid lodge, as well as

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1974-449: The sixth week of the prenatal development and are the first major salivary glands formed. The epithelial buds of these glands are located on the inner part of the cheek, near the labial commissures of the primitive mouth (from ectodermal lining near angles of the stomodeum in the 1st/2nd pharyngeal arches; the stomodeum itself is created from the rupturing of the oropharyngeal membrane at about 26 days. ) These buds grow up posteriorly toward

2021-560: The supporting connective tissue of the gland develops from the surrounding mesenchyme . Inflammation of one or both parotid glands is known as parotitis . The most common cause of parotitis is mumps . Widespread vaccination against mumps has markedly reduced the incidence of mumps parotitis. The pain of mumps is due to the swelling of the gland within its fibrous capsule. Apart from viral infection, other infections, such as bacterial, can cause parotitis (acute suppurative parotitis or chronic parotitis). These infections may cause blockage of

2068-556: The tumor to the branches of the facial nerve ( CN VII) must be defined because resection may damage the nerves, resulting in paralysis of the muscles of facial expression. Neoplastic lesions of the parotid salivary gland can either be benign or malignant. Within the parotid gland, nearly 80% of tumours are benign . Benign lesions tend to be painless, asymptomatic and slow-growing. The most common salivary gland neoplasms in children are hemangiomas , lymphatic malformations, and pleomorphic adenomas . Diagnosis of benign lesions require

2115-512: The two parotid glands are present on either side of the mouth and in front of both ears . They are the largest of the salivary glands. Each parotid is wrapped around the mandibular ramus , and secretes serous saliva through the parotid duct into the mouth, to facilitate mastication and swallowing and to begin the digestion of starches . There are also two other types of salivary glands; they are submandibular and sublingual glands. Sometimes accessory parotid glands are found close to

2162-428: The tympanic plexus in the lesser petrosal nerve to the otic ganglion where they synapse. Postganglionic (post-synaptic) fibers from the ganglion then "hitch-hike" along the auriculotemporal nerve to reach the parotid gland. Sensory General sensory innervation to the parotid gland and its capsule is provided by the auriculotemporal nerve . The gland has a capsule of its own of dense connective tissue but

2209-418: The upper buccal nerve . The lower buccal nerve runs inferiorly along the duct. Blockage, whether caused by salivary duct stones or external compression, may cause pain and swelling of the parotid gland ( parotitis ). Koplik's spots which are pathognomonic of measles are found near the opening of the parotid duct. The parotid duct may be cannulated by inserting a tube through the internal orifice in

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