oral radiology

Salivary Glands diseases

Ashjan AL-Rashidi Esraa Halawah Mariam AL-Mansour Fatemah Bughaiss

We have Major and minor salivary glands .

The major are : parotid gland , submandibular gland and sublingual gland.

Both major and minor salivary glands maybe involved pathologically , but the major accounts more.

Salivary Glands

Salivary gland diseases are divided into three categories according to processes :

1. inflammatory disorders. 2. non-inflammatory disorders. 3. space occupying masses : A. cystic. B. neoplastic ( benign or malignant ).

Salivary gland diseases

The inflammatory diseases can be :

A. acute or chronic. B. secondary to ductal obstruction ( sialoliths ) or infections.

C. secondary to trauma or neoplasms.

Salivary gland disease

The clinical signs and symptoms of salivary glands disorders are :

1. swelling. 2. pain. 3. altered salivary glands.

Salivary glands disease

Differential diagnosis of salivary glands

enlargement

The diagnostic imaging is very important to differentiate , distinguish , identify and localize the salivary gland diseases.

Applied diagnostic imaging

These are an intra-oral peri-apical and occlusal radiograph for the mandible showing sialolith in the anterior two thirds of the submandibular duct (wharton’s duct).

Intra-oral radiograph

This is an extra-oral radiograph projection that has been taken

with over-the-shoulder occlusal technique showing a sialolith in posterior part of wharton’s duct.

Extra-oral radiograph

These are panoramic radiographs : A. this panoramic radiograph shows submandibular sialolith near the antegonial notch of the mandible and superior to hyoid bone.

Extra-oral radiograph

B. this panoramic radiograph shows parotid sialolith superimposed over the condyler neck.

Extra-oral radiographs

These are sialography of normal parotid gland showing opacification all the way to the terminal ducts and acini :

A. ant. Post. projection.

Conventional sialography

B. lateral projection.

Conventional sialography

These are conv. Sialography of a submandibular g. imaged with cone beam computed tomography (CBCT) :

A. axial view.

Conventional sialography

B. lateral view.

Conventional sialography

These are CBCT imaging of a submandibular sialolith :

Coronal , axial and 3D views.

CBCT image

These are CT image with soft tissue algorithm demonstrates bilat. enlargement of the parotid glands :

Axial view.

CT image

Coronal view.

CT image

This an axial bone algorithm MDCT image shows a sialolith in the submandibular wharton’s duct.

MDCT image

disease mechanism :  it is the formation of a calcified obstruction within the salivary duct.  the submandibular gland and Wharton's duct ( 83% of cases )

obstructive and inflammatory disorders (1. sialolithiasis)

clinical features : 1. swelling.2. pain with eating.3. signs of infection.

obstructive and inflammatory disorders (1. sialolithiasis)

imaging features : it depends on the degree of calcification , it may appears :a. radiopaque or radiolucent.b. varies from long cigar shapes to oval round shapes.  * sialography is helpful in locating obstructions *

obstructive and inflammatory disorders (1. sialolithiasis)

1. sialolithiasis

treatment :1. it is done by stimulating the secretion through the use of sialagogues. 2. If the discharge does not occur , then sialolith maybe removed by surgery.  3. as a last choice , by total excision of the involved gland.

obstructive and inflammatory disorders (1. sialolithiasis)

disease mechanism :it is an acute or chronic bacterial infxn of the terminal acini or parenchyma of the salivary glands. a. acute type:- parotid gland is the most affected.- as a result of reduced salivary secretion o & retrograde by oral flora.

b. chronic type:-maybe a consequence of an untreated acute sialadenitis.-may affect any of the major glands ( mostly parotid ).

obstructive and inflammatory disorders ( 2. bacterial sialadenitis )

clinical features : 1. unilat & it occur at any age.

a. in acute cases :- swelling , redness , tenderness and malaise.- enlarged regional lymph nodes and suppuration.  b. in chronic cases :- pus expression.- pain during salivary stimulation.

obstructive and inflammatory disorders ( 2. bacterial sialadenitis )

imaging features : -sialography is contra-indicated in acute cases ! however , sialography is good for chronic infxns.  -MDCT will show the abscess cavities. -US will distinguish between diffuse infl. and suppuration.and will detect sialolith greater than 2 mm. -MRI is an alternative when the sialography is contra-indicated. 

obstructive and inflammatory disorders ( 2. bacterial sialadenitis )

2. bacterial sialadenitis

treatment : 1. oral hygiene , local massage , fluid intake , oral sialagogues.2. antibiotic. 3. partial or total surgical excision. 

obstructive and inflammatory disorders ( 2. bacterial sialadenitis )

disease mechanism : it is an inflammatory of the ductal system of the salivary glands. dilation of the involved ductal system. in chronic cases ,fibrosis may show causing obstructions. common in both the submandibular and the parotid gland.  

obstructive and inflammatory disorders ( 3. sialodochitis )

imaging features : sialectasia is prominent manifestation of sialodochitis on sialography.  if fibrosis develops , it will appear as a sausage-string.   treatment : similar to that describe to sialadenitis.

obstructive and inflammatory disorders ( 3. sialodochitis )

3. sialodochitis

Synonym : it include myoepithelial sialadenitis

Sjogren syndrome Benign lymphoepithial lesion Disease mechanism : defferent

devolopmental stage of the same immunologic mechanism

Autoimmune sialadenitis

Range from reccurent painless swelling of S.G to enlarge of lacremal gland

glandular swelling may accompained by :

- xerostomia ,exophthalmic ( primary sjogran syndrom )

- Subsequently by C.T disease such as : rheumatoid arithritis , systamic lupus erythamtous

Clinical feature

Made on the basic of any 2 of the 3 feature :

1- Dry mouth 2- Dry eyes 3- rheumatoid disease

common in : Adult (40-60 years ) Female 95% • Non hodgkin lymphoma • Mikulics disease

Diagnosis

sialograph is helpful in diagnosis and staging of autoimmune disease

*Early stage *Disease progress *End stage  

Imaging Feature: 

- Chronic bacterial granulomatous in infection

- Multiple parotid cyst associated with HIV *Diffuse cervical lymphadenopathy is common in HIV uncommon in sjogran syndrome  

D/D :

 - Relive symptom - The underlyining rheumatoid condition   are treated with :  *Antiinflammatory agent  *corticosteriod  * Immunosuppressive therapeutic agent

Treatment :

1- Sialadenosis2- Cystic Lesions3- Benign tumers : Benign Mixed Tumor                                     Warthin Tumor                                     Hemangioma4- malignant tumers :                                 Mucoepidermoid Carcinoma                                 Malignant Mixed Tumor 

Non Inflammatory Disorder

-non-neoplastic -non-inflammatory enlargment of primary parotid gland  

Related to:Metabolic and secretory disease

Associated with :-vitamin and protein deficiencies - neurologic disorders

Disease mechansim :

enlargment of S.G

Imaging Feature :enlargment of the effected S.G and the duct are splayed

Clinical Feature :

- Identify the cause of the metabolic and secretory disorder

- Conservative treatment : -local massage - increased fluid intake - use of oral sialagogoues

Treatment :

Disease Mechanism :-rare -unlateral -conginital or acquired -intraglandular or extraglandular

Clinical Feature :palpable *must be distinguished from neoplasia*

Cystic lesion

-cystic mass may indirectly visualized on sialography only by the displacement of the duct arch around them.-it’s appear well circumscribed - low density area when examined on CT -high signal area on MRI but do not enhance after administration of gadolinium

Imaging Feature

- typically surgical involving : local or total excision of the gland

Treatment

Extravasation has pseudocyst:  lack an epithelial lying and result from duct rupture

*Ranulas: are retention cyst result from obstruction of sublingual duct

*Multicentric parotid cyst associated with HIV

*Bengin lymphoepithelial lesion of human immunodeficiency syndrome

Disease mechanism : Prevalence < 0.003% of population . It's 3% all tumors in body . Benign and low -grade malignancy >

high-grade malignancy . chance of being benign varies directly

with size .

BENIGN TUMOR

parotid gland 80%

Treatment: major salivary glands is surgical

removal .

Imaging feature: Benign and low -grade malignancy are1. Well-defined margin (especially MDCT & MRI) 2. Ball in hand appearance ( MRI )

Disease mechanism : Arising from the ductal epithelium of

major and minor salivary glands

PLEOMORPHIC ADENOMA (BINGHN MIXED TUMOR )

.

Clinical features :1. 75% of all salivary gland tumors .2. Fifth decade .3. Female > male .4. Slow-growing , Unilateral , Encapsulated , Asymptotic .5. 50% recurrence after excision 6. 15% malignant transformation

.

parotid gland 80%submandibular gland 4%

Imaging features: In MDCT 1.sharply circumscribed 2. Round homogeneous lesion 3. Higher density 4. Calcifications within tumor

Disease mechanism : arising from proliferating salivary ducts

trapped in lymph nodes during embryogenesis .

WARTHIN'S TUMORS ( PAPILLARY CYSTADENOMA LYMPHOMATOSUM –

ADENOLYMPHOMA – LYMPHOMATOUS ADENOMA )

Clinical features :1.second most common benign tumors .2. 2-6% of parotid tumor and found in the inferior lobe .3. More in men older than 40 years .4. Slow-growing , Painless .4. Rond-to-avoid mass .5.Unilateral or bilateral

Imaging Features. MDCT and MRI are preferred techniques 1. Similer to benign mixed tumor . 2.either soft tissue or cystic density (on MDCT). 3. heterogeneous and may hemorrhagic foci (on MRI) .

Diseae Mechanism : Arising from proliferating endothelial cells

(congenital hemangioma) and vascular malformation

Hemangioma ( vascular nevus )

Clinical Feature: 1. Most frequently occurring non-epithelial salivary gland neoplasm (especially during infancy and childhood)2. 85% in parotid gland .3. 50% Hemangioma4. Unilateral , asymptomatic5. 2:1 female:male .

Treatment is local excision if it's not undergo

spontaneous remission .

Imaging Features: 1. Phleboliths .2. the ducts of the gland may be displaced curving about the mass ( sialography )3. hemangioma ( MDCT especially when intravenous contrast enhancement is used )4. has a signal similar to that of adjacent muscle on TI-weighted images and a very high signal on T2-weighted images (MRI)

Dieese Mechanisms:

1. 20% of the parotid gland tumors

2. 50-60% of submandibular tumors

3. 90% of sublingual tumors

4. 60-75% of minor salivary gand tumors

Malignant Tumors

Treatment Management

1. major salivary glands is typically surgical.

2. Radiation therapy

3. Chemotherapy

Imaging Features :

1. variable and it's related to the grade , aggressiveness , location and type of tumor.

2. ill-defined .

3. invasion of djacent soft tissues .

4. destruction of adjacent osseous structure .

Diseae Mechanism :

variable admixture of epidermoid and mucous cells arising from the ductal epithelium of the salivary glands .

Mucoepidermoid carcinoma

Clinical features:1. the most common malignant salivary gland tumor . 2. more than half occur in the major salivary glands (parotid gland) . 3. the rest are found in the minor glands (palate). 4. fifth decade of life.5. females > male 6. Low-grade tumors : mobile , slowly growing , painless , 1-4 cm in diameter , rarely metastasis and the prognosis is good. 7. high- grade tumors : immobile , painful , paralysis , ill-defined margins , metastasis by blood and lymph recurrence in half of patients after excision and the prognosis is poor .

Imaging Features :

1.Low-grade tumors : *not apparent unless destructive changes to adjacent osseous structures have occurred *Presentations similar to benign salivary tumors. * may lobulated or irregularly sharply circumscribed appearance ( in contrast-enhanced MDCT and MRI)

2. high-grade tumors : irregular margins , ill-defined form (MDCT or MRI)

3. irregular homogeneous mass , slightly more dense than the glandular tissues (MRI)

4. Homogeneous low signal intensity (dark) on TI-weighted images, but T2-weighted images are more heterogeneous and intense (brighter) ( MRI).

5. Cavitary sialectasia and ductal displacement may be noted (on sialography )

1. adenoid cystic carcinomas (minor salivary glands).

2. Adenocarcinoma3. acinic cell carcinoma4. primary lymphoma5. squamous cell carcinoma

Other Malignant and Metastatic :

Clinical features:

1. Pain, paresthesia, and paralysis in high-grade Tumors 2. Tumor spread may be by direct invasion or metastatic 3. Metastasis lesions in the parotid gland are more common because of the extensive lymphatic and circulatory components *the lymphatic system include: squamous cell carcinoma, lymphoma, and melanoma *hematogenous dissemination: metastasis from the lung, breast, kidney, and gastrointestinal tract

Imaging Features.

The presentation similar to high-grade mucoepidermoid carcinoma