Salivary Glands Didease 2012 Final Yr Lecture
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Transcript of Salivary Glands Didease 2012 Final Yr Lecture
DIAGNOSIS AND MANAGEMENT OF SAIVARY GLAND DISORDERS
DR.TAHERA AYEUBASISSTANT PROFESSOR
ORAL AND MAXILLOFACIAL SURGERY DEPARTMENT
EMBRIOLOGY ANATOMY AND PHYSIOLOGY
• Divided into two groups minor glands major glands -Develop from embryonic oral cavity as buds of
epithelium that extend into underlying mesenchymal tissues
-epithelium in growth branch to form a primitive dental system-canalized to provide for drainage of salivary secretion
• Development begin -minor salivary gland-fortieth day in utero -major salivary gland-thirty fifth day in utero -secretory cell around the ductal system-7th
or 8th month in utero
SALIVARY GLAND RADIOLOGY
• TO IDENTIFY SALIVARY STONES(CALCULI)• 80% TO 85% stones are radiopaque • Visible radiographically• Mandibular occlusal film is use for detecting
sublingual and sub mandibular gland calculi in the floor of the mouth
• Panoramic radiograph reveal stones in the parotid gland and posteriorly located submandibular gland
• Periapical radiograph can show calculi in each salivary gland and minor salivary gland
PAROTID GLAND
• Largest salivary gland• Lie superficial to the posterior aspect of
masseter muscle and assending ramus of mandible
• Peripheral portion extend to the mastoid process along the anterior border of the sternocleidomastoid muscle
• Around the posterior border of the mandible into the pterogomandibular space
• seventh cranial (facial) nerve divide the parotid gland into
-superficial lobe -deep lobe• Coursing anteriorly from their exit at the
stylomastoid foramen to the innervate the muscle of expression
• Small ducts from various regions of the gland coalesce at the anterosuperior aspect of the parotid to form stensen's duct
• Stensen's duct 1 to3mm in diameter and 6cm in length
• At the anterior edge of the masseter Stensens duct turns medial and passes through the fibers of the buccinators muscle
• The duct opens into the oral cavity through buccal mucosa adjacent to maxillary 1st and 2nd molar tooth
• Gland receive innervation from ninth cranial (glossopharyngeal)nerve with auriculotemporal nerve from the otic ganglion
SUBMANDIBULAR GLANDS
• Located in the submandibular triangle of the neck• Which is formed by anterior and posterior belly of
digastrics muscles and inferior border of the mandible
• Poster-superior portion of the gland curves upward around the posterior border of the mylohyoid muscle
• Give rise to the major duct of the submandibular gland known as Wharton's duct
• Duct passes forward along the superior surface of the mylohyoid muscle in the sublingual space ,adjacent to the lingual nerve
• Lingual nerve loops under wartan,s duct from lateral to medial in the posterior floor of the mouth
• Duct is 5cm in length • Diameter of lumen is 2 to 4 mm• Wharton's duct open into the floor of the
mouth with a punctum
• Punctum located close to the incisors at the most anterior aspect at the lingual frenum and the floor of the mouth
SUBLINGUAL GLANDS
• Lie on the superior surface of the mylohyoid muscle, in the sublingual space
• Are separated from oral cavity by a thin layer of oral mucosa
• Acinar ducts of the sublingual glands are bartholins duct in most instance coalesce to form 8 to 20 ducts of rivinus
• Short and small in diameter• open directly into the floor of the mouth on a
crest of mucosa known as plica sublingualis
• Or they open indirectly through connection to the submandibular duct and then into the oral cavity with wharton's duct
• Submandibular and sublingual glands are innervated by the facial nerve through the submandibular ganglion with the chorda tympani nerve.
FUNCTIONS OF SALIVA
• Provide lubrication for speech and mastication• To produce enzymes for digestion• To produce compounds with antibacterial
properties• Produce 1000 to 1500 saliva per day with the
highest flow rates occurring during meals
Daily saliva production by salivary glands
• Submandibular gland 70%• Parotid gland 25%• Sublingual gland 3% to 4%• Minor glands trace
Diagnostic modalities
• HISTORY AND CLINICAL EXAMINATION -In most cases patient will guide the doctor to
the diagnosis by relating the events that have occurred in association with the presenting complaint
• Must perform a thorough evaluation for diagnosis
• Many instances diagnosis can be determined without further diagnostic evaluation
• Occasionally the clinician may find it necessary to use any of several diagnostic modalities
- salivary gland radiology - salivary gland endoscopy(sialoendoscopy) - sialochemistry - fine-needle aspiration biopsy - salivary gland biopsy
SALIVARY GLAND RADIOLOGY
• PLAIN FILM RADIOGRAPHS - in the assessment of salivary gland disease is
to identify salivary stones(calculi) - 80% to 85% stones are radio opaque - mandibular occlusal film is most useful for
submandibular and sublingual gland calculi in the anterior floor of the mouth
SIALOGRPHY
Indications• in the detection of radio opaque stones • In the assessment of the extent of destruction
of salivary duct or gland as a result of -obstructive , inflammatory, traumatic and
neoplastic diseases
COMPUTER TOMOGRAPHY
• For the assessment of mass lesions of the salivary glands
• Less invasive than sialography• Does not require the use of contrast material• Demonstrate salivary gland calculi • Especially submandibular stones that are
located posteriorly in the duct or in the substance of the gland itself
Magnetic resonance imaging(MRI)
• Superior to CT scanning in delineating the soft tissue detail of salivary gland lesions
• Specifically tumors , with no radiation exposure to the patient
ULTRASONOGRAPHY
• Simple , noninvasive imaging modality• Poor detail resolution• Role is in the assessment of superficial
structures• To determine whether a mass lesion is solid or
cyst(fluid-filled) in nature
SALIVARY SCINTIGRAPHY(RADIOGRAPHIC ISOTOPE SCANNING)
• Use of nuclear imaging in the form of radioactive isotope scanning
• Allows a thorough evaluation of the salivary gland parenchyma
• Presence of mass lesions• Function of the gland itself• Demonstrate increased uptake of radioactive
isotope in an acutely inflamed gland• Decrease uptake in chronically inflamed gland• Presence of a mass lesion(benign or malignant)
SALIVARY GLAND ENDOSCOPY(SIALOENDOSCOPY)
• Minimally invasive modalities of diagnosis and treatment• Applied to the major salivary glands• Is a specialized procedure that uses a small video
camera(endoscope)• With a light at the end of a flexible canula• Introduced into the ductal orifice• Can be used diagnostically and therapeutically• Used to dilate small strictures• Flush clear small mucous plugs in the salivary gland ducts• Specialized devices such as small balloon catheters used to dilate
sites of ductal constriction• Small baskets may be used to retrieve stones in the ductal system
SIALOCHEMISTRY
• An examination of the electrolyte composition of the saliva of each gland
• May indicate a variety of salivary gland disorders
• Concentration of sodium and potassium change with salivary flow rate
• Elevated sodium concentration with decreased potassium concentration may indicate an inflammatory sialadenitis
FINE NEEDLE ASPIRATION BIOPSY
• Use in the diagnosis of salivary gland tumors'• Has a high accuracy rate for distinguishing
between benign and malignant lesion in the superficial location
• Is performed using a syringe with a20-guage or smaller needle
PROCEDURE
• local anesthesia• Needle is advanced into the mass lesion• The plunger is activated to create a vacuum in the
syringe • The needle is moved back and forth throughout the
mass with pressure maintained on the plunger• The pressure is then released the needle is withdrawn• The cellular material and fluid is expelled onto a slide
and fixed on histologic examination•
SALIVARY GLAND BIOPSY
• Either incisional excisional biopsy can be used to diagnosed tumor of one of the major salivary glands
• The lower lip labial salivary gland biopsy has been shown to demonstrate certain characteristic histopathology changes that are seen in the major glands in ss
• The procedure is performed using local anesthesia• Approximately 10 minor salivary glands are
removed for histological examination
OBSTRUCTIVE SALIVARY GLAND DISEASE
Sialolithiasis• formation of stones or calculi may occur
throughout the body• Including gallbladder, urinary tract and salivary
glands• Common in men • Age between 30 and 50• Multiple stone formation in 25% of patients
• The pathogenesis of salivary calculi progresses through a series of stages beginning with an abnormality in calcium metabolism and salt precipitation
• Formation of a nidus that subsequently becomes layered with organic and inorganic material,to form a calcified mass
• Submandibular gland involve 85%• Concentration of calcium is about twice as
abundant in submandibular saliva as in parotid saliva
• Alkaline Ph of submandibular saliva may further support stone formation
• Wharton,s duct is longes salivary duct –has a greater distance to travel before being emptied into the oral cavity
• The punctum of submandibular gland is smaller -provide potential areas of stasis of salivary flow or
obstruction -precipitated material mucous and cellular debris are
more easily trapped in the tortuous and submandibular duct
• Obstruction occurs at meal time because salivary production maximum
SIALOLITHIASIS FOR GENERAL DENTIST
• Classic signs and symptoms of sialolithiasis - exacerbation of pain and swelling at
mealtimes - check for flow from wahrton,s duct - check for tenderness of submandibular
gland - Palpate for stone in floor of mouth - check mandibular occlusal radiograph
MANAGEMENT
• the management of submandinbular gland calculi depends on
- the duration of symptoms - the number of repeated episodes - the size of the stone - the location of the stone
SIALODOCHOPLASTY(revision of the salivary duct)
• An incision made floor of the mouth• Expose the duct and stone• A longitudinal incision is then made in the
duct ,the stone is retrieved• The ductal lining is sutured to the mucosa of
the floor of the mouth• Saliva will then flow out the revised duct
• In many instances of repeated stone formation• The submandibular gland and the stone
should be removed by an extra oral approach
Counciling of the patient
• Patients are encourage to maintain ample salivary flow by using salivary stimulants
- citrus fruits - flavored candies - glycerin swabs
EXTRACORPOREAL SHOCK WAVE LITHOTRIPSY
• Successful in treating small salivary gland stones
• This technology uses transcutaneous electromagnetic waves to break the calculus into small calcified debris particles
• Flushed from the ductal system by the normal flow of saliva
• This procedure is limited by - the size of stone(usually less than 3mm) - the number of stones(usually less than three) - the location of the stone(intraglandular
stones may be less amenable to ecswl)
MUCOUS RETENTION AND EXTRAVASATION PHENOMENA
• MUCOCELE what is mucocele? . Salivary duct, especially those of the minor
salivary glands ,are occasionally traumatized commonly by lip biting, and severed beneath the surface mucosa.
. Subsequently saliva production may then extravsate beneath the surface mucosa into the soft tissues
. Over time ,secretions accumulate within the tissues and produce a pseudocyst that contains thick viscous saliva common in mucosa of upper lip known as mucoceles
second common site is buccal mucosaMucocele formation results in an
elevated,thinned, stretched overlying mucosa that appears as a vesicle filled with a clear or blue-gray mucus.
The patient frequently relates a history of the lesion filling with fluid, rupture of the fluid collection, and refilling of these lesion
Mostly mucocele formation regress spontaneously without surgery
Persistent or recurrent lesions – treatment consist of exicision of the mucocele and associated minor salivary glands
Recurrence rates may be as high as 15% to 30% after surgical removal
• RANULARanulas results from either mucous retention
in the sublingual gland ductal system or mucous extravasation as a result of ductal disruption
Most common lesion of sublingual gland Two types of ranulas are - simple ranula - plunging ranula
First recurrence of ranula
Third recurrance of ranula
Fifth recurrance of ranula
• Simple ranula is confined to the area occupied by the sublingual gland in the sublingual space, superior to the mylohyoid muscle
• Plunging ranula occures when the lesion extends beyond the level of the mylohyoid muscle into the submandibular space
- plunging ranula has the potential to extend into the neck and compromise the airway, resulting in medical emergency
• Ranulas may reach a larger size than mucoceles because their overlying mucosa is thicker and because trauma that would cause their rupture is less likely in the floor of the mouth
Treatment of ranula• Is marsupilization• In which a portion of the oral mucosa of the
floor of the mouth is excised along with the superior wall of the ranula
• The ranula wall is sutured to the oral mucosa of the floor of the mouth and allowed to heal by secondary intention
• The preferred treatment for recurrent or persistant ranulas is excision or the ranula and sublingual gland
SALIVARY GLAND INFECTIONS
• Related to obstructive disease, especially in submandibular gland
• Cause of acute suppurative sialadenitis of the parotid gland usually involves a change in fluid balance that is likely to occur in patients who are
-elderly -debilitated -malnourished -dehydrated -plagued with chronic illness• In these cases , gland infections are usually bilateral
• Mean age of infection is is 60 years• Organisms including aerobic and anaerobic ,
bacteria, viruses , fungal organisms and mycho bacteria
• In most cases mixed bacterial flora is responsible for sialadenitis
• The most common organism implicated in salivary gland infection is staphylococcus aureus
• This organism normally colonizes around ductal orifices
Clinical characteristics of acute bacterial salivary gland infections
• Is rapid onset of swelling in the pre auricular(parotid gland)or submandibular regions
• Associated erythema and pain• On palpation gland will reveal no flow or elicit
a thick purulent discharge from the orifice of the duct
TREATMENT 0F BACTERIAL SALIVARY GLAND INFECTIONS
• Includes symptomatic and supportive care• Including IV fluid hydration, antibiotics ,and
analgesics• Initial empiric antibiotics should be aimed at the
most likely causative organism s. aureus• Should include a cephalosporin or anti
staphylococcal semi synthetic penicillin• Culture and sensitivity studies of purulent material
should be obtained to aid in selecting the most appropriate antibiotic for each patient
• In most cases, surgery consist of incision and drainage
• Untreated infection may progress rapidly and can cause
-respiratory obstruction -septicemia and eventually death• In recurrent infections , excision of the gland
may be indicated
Viral parotitis or mumps
• Is an acute ,non suppurative communicable disease
• Occurred in epidemics during winter and spring
• Viral infections are not the result of obstructive disease
• Not require different treatment ,not including antibiotics
• Mumps is characterized by a painful ,non erythematous swelling of one or both parotid glands
• Begins 2 to 3 weeks after exposure to the virus• Common in children between ages 6 and 8• Signs and symptoms pain swelling fever chills headache• Usually resolves in 5 to 12 days after its onset
• Supportive and symptomatic care for -fever -headache -malaise with antipyretics -analgesics -adequate hydration treats viral partitas• Complications in 20% of young males -meningitis -pancreatitis -nephritis -orchitis -testicular atrophy
NECROTIZING SIALOMETAPLASIA• Is a reactive nonneoplastic inflammatory process that
usually affects the minor salivary glands of the palate• Unclear origin but is thought to be secondary to
vascular infarction of the salivary gland lobules• Potential causes of diminished blood flow to the
affected area including trauma, local anesthetic injection smoking, diabetes mellitus, vascular disease pressure from denture prosthesis• Age range is 23 and 66 years
• Lesions usually 1 to 4 cm large• Painless or painful• Deeply ulcerated areas lateral to the palatal midline and
near the junction of the hard and soft palate• Unilateral or bilateral involvement may occur• Patient may report a prodromal flulike illness before the
onset of the ulceration• It resembles a malignant carcinoma(squamous cell or
mucoepdermoid carcinoma)• The ulceration of necrotizing sialometaplasia usually heal
spontaneously within 6 to 10 weeks after their onset• No surgical management
SJOGRENS SYNDROME
• Is a multisystem disease process with a variable presentation
• Two types of ss are 1- primary ss or sicca syndrome . Charecterized by xerostomia(dry mouth) . Keratocunjuctivitis sicca(dry eyes) 2- secondary ss . Composed of primary ss and an associated
connective tissue most commonly rheumatoid arthritis
• Cause of ss is unknown• There appears to be a strong autoimmune
influence• The first symptoms to appear are arthritic complaints followed by occular symptoms late in the disease proses Salivary gland symptoms• Xerostomia results from a decreased function
of both the major and minor salivary glands
DIAGNOSIS
• By the patient complaints complaints • By immunological laboratory tests• By using salivary flow rate studies• Sialography• Labial minor Salivary gland biopsy
Treatment
• SYMPTAMATIC - artificial tears for dry eyes - salivary substitute for dry eyes• MWDICATION - pilocarpine(salagen) - biotene products to stimulate salivary
flow from the remaining functional salivary gland tissue
TRAUMATIC SALIVARY GLAND INJURIES
• Occur in close proximity to one of the major salivary glands or ducts
• Due to trauma, fractures, • Repair may include ductal anastomoses• In which the proximal and distal portions of the
duct are identified• A plastic or metal catheter is placed as a stent • The duct is sutured over the stent• Catheter leave for 10 to 14 days for
epithelialization of the duct
• Trauma involve the major salivary glands include infection-facial paralysis-cutaneous salivary gland fistula –sialocele formation and duct obstruction as a result of scar formation-evantually glandular atrophy-require surgical removal
NEOPLASTIC SALIVARY GLAND DISORDERS
• Salivary gland tumor distribution Major salivary gland parotid glands 85% to 90% submandibular gland 5% to 10% sublingual gland rare Minor salivary gland palatal 55% lips 15% remainder rare
BENIGN SALIVARY GLAND TUMORS
• pleomorphic adenoma or benign mixed tumor
• warthin,s tumor or papillary cytadenoma lymphomatosum
• Monomorphic adenoma
Pleomorphic adenoma
• Most common salivary gland tumor • Occurrence age is 45 years• Male to female ratio 3:2• In major glands parotid gland is involved 80%• Minor glands intraoral sit is the palate• Slow growing painless masses• Histopathology shows two types of cell 1- ductal epithelial cell 2-myoepithelial cell
• Treatment - complete surgical excision with a margin
of normal uninvolved tissue - parotid lesion-removal of involved lobe
along with tumor - recurrene is possible in rare cases - small risk 5% of malignant transformation
Warthans tumor or papillary cystadenomatosum
• Affect the parotid gland• Specifically the tail of the parotid gland• Peak incidence is sixth decade of life• Male to female ratio 7:1 • Slow growing soft and painless mass• Caused by entraped salivary epithelial rests
within developing lymph nodees
• Histopathology epithelial component in a papillary pattern Slymphoid component with germinal centers • Treatment surgical excisionRecurrence is rare
Malignant salivary gland tumors
• Mucoepidermoid carcinoma• Polymorphous low grade adenocarcinoma• Adenoid cystic carcinoma
Mucoepidermoid carcinoma
• most common malignant salivary gland tumor• 10% major gland tumor(mostly parotid)• 20% minor gland tumors(mostly palate)• Mean age is 45 years• Male to female ratio is 3:2• Clinical presentation –submucosal mass-
painful or ulcerated
• Histopathology show three cell types -mucous cells -epidermoid cells -intermediate (clear) cells
• Treatment - low grade lesion –wide surgical removal with
margins of uninvolved normal tissue -95% 5-year survival rate -high grade lesions require more aggressive
surgical removal with margins -local radiation therapy - less than 40% 5-year survival rate
Polymorphous low-grade adenocarcinoma
• Second most common malignant tumor• Most common sit is the junction of hard and
soft palate• Mean age 56-year• Male to female ratio is 3:1• Slow growing asymptomatic masses• May be ulcertaed
Polymorphous low grade adenocarcinoma
• Histopathology shows many cell shapes and patterns(polymorphous)
• Patient experienced an infiltrative proliferation of ductal epithelial cells in an indian file pattern
• Invasion of surrounding nerves• Treatment-WIDE SURGICAL EXCISION• Recurrence rate is 14%
ADENOID CYSTIC CARCINOMA
• Third most common intraoral salivary gland malignancy
• Mean age 53 years• Male to female ratio 3:2• 50% in parotid gland• 50% occur in minor salivary gland• Slow growing nonulcerated masses• Associated chronic dull pain
• Parotid lesion may result in facial paralysis as a result of facial nerve involvment
• Histopathology – infiltrative proliferation of basaloid cells arranged in a cribriform (swiss cheese) pattern
• Treatment - wide surgical excision - in some cases radiation therapy - Prognosis is poor
Necrotizing sialometaplasia