This describes the various imaging modalities used in salivary glands.

1. Melbia Shiny

2. Introduction
Major salivary glands
 Parotid
 Submandibular
 Sublingual
Minor salivary glands
 Labial glands
 Lingual glands
Von Ebner’s gland.
Glands of Blandin’s and Nuhn’s.
 Buccal glands
 Palatine glands (weber’s gland)

3. Evaluation of salivary glands
 Main salivary gland complaints and causes
1)Acute intermittent generalized swelling.
 Sialolithiasis
 Stricture/stenosis
 Recurrent juvenile parotitis
2)Acute generalized swelling
 Infection – Viral,Bacterial

4. 3)Chronic generalised swelling
 Sjogren’s syndrome
 Sialosis
 Cystic fibrosis
 Sarcoidosis
4)Discrete swelling
 Intrinsic tumor – benign,malignant.
 Extrinsic tumor
 Cyst
 Lymph nodes

5. 5)Dry mouth
 Sjogren’s syndrome
 Post radiation
 Mouth breathing
 Dehydration
 Drugs
 Systemic diseases

6. 6)Excess salivation
 Reflex
 Heavy metal poisoning
 Systemic diseases
 Parkinsonism
 Epilepsy

7. Physical examination
Inspection
 Intra oral inspection – duct orifice
 Extra oral inspection –
Colour,symmetry,pulsation,sinus discharge.
Palpation
 Extra oral -
 Intra oral
 Bimanual palpation

8. Differential diagnosis of
enlargement in salivary gland
1)Parotid area:
Unilateral
 Bacterial sialadenitis
 Sialodochitis
 Cyst
 Benign neoplasm
 Malignant neoplasm
 Intraglandular lymph node
 Masseter muscle hypertrophy
 Lesions of adjacent osseous structures

9. Bilateral
 Bacterial sialadenitis
 Viral sialadenitis
 Sjogren syndrome
 Alcoholic hypertrophy
 Medication induced hypertrophy(I, heavymetal)
 HIV
 Masseter muscle hypertrophy
 Accessory salivary gland
 TMJ related

10. 2)Submandibular area
Unilateral
 Bacterial sialdenitis
 Sialodochitis
 Fibrosis
 Cyst
 Benign neoplasm
 Malignant neoplasm

11. Bilateral
 Bacterial sialadenitis
 Sjogren’s syndrome
 lymphadenitis
 Branchial cleft cyst
 Space infection

12. Imaging modalities
1)Plain radiography.
Parotid - Intra oral view of cheek.
Lateral oblique.
Panoramic.
Submandibular - lower 90 degree occlusal.
lower oblique occlusal.
Lateral oblique.
Panoramic.

13. 2)Sialography.
Conventional sialography.
MR sialography.
CBCT sialography.
3)Ultrasound.
4)Computed Tomography.
5)Multidetector computed tomographic imaging
5)Magnetic resonance.
6)Radioisotope imaging.
7)Sialendoscopy.

14. Intra oral radiography
For Wharton’s duct sialolith
In anterior 2/3 rd
of submandibular
duct

15. Mandibular occlusal view

16. Extraoral radiography
 Panoramic view – both parotid & submandibular duct
sialolith.
 Lateral oblique view of submandibular gland (modified)

17. Parotid calculi
AP view with cheek blown out. – sialolith in distal
portion

18. Conventional Sialography
Defined as radiographic demonstration of major salivary
glands by introducing a radiopaque contrast medium into
their ductal system.
Stones & strictures.
First - 1902
 The preoperative phase
 The filling phase.
 The emptying phase.

19. Preoperative phase:
 scout radiographs.
 Position of radiopaque obstruction.
 Position of normal anatomical structures.
 Exposure factors.

20.  Filling Phase :

21. Filling
phase:

22. Techniques:
1)Simple injection.
2)Hydrostatic.
3)Continuous infusion pressure monitored.
Filling phase radiographs at two different views at right
angles to each other.

23. Simple injection technique:
 oil based /aqueous contrast media .
 Gentle hand pressure till tightness /discomfort is felt.
 Parotid – 1 ml,submandibular – 0.8 ml.
 Simple & cheap.
 Arbitary pressure - under or over filling due to patient
response.

24. Hydrostatic technique
 Aqueous contrast media – overhead reservoir under
force of gravity.
 Simple ,inexpensive.
 Pt lying position and position for filling phase
radiographs.

25. Continuous infusion pressure monitored
technique:
 Aqueous contrast media and ductal pressure monitored.
 No damage/overfilling of gland.
 Independent of pt response.
 Complex equipment.
 Time consuming.

26. Emptying phase:
 Removal of cannula & pt asked to rinse.
 Lemon juice aids in excretion.
 Emptying phase radiographs.

27. Submandibular gland

28. Contrast agents in sialography
Iodine based
 Ionic aqueous solution
Diatrizoate(urografin).
Metrizoate(triosil).
 Non ionic aqueous solution
Iohexol (omniopaque).
Oil based solution
 Iodized oil (lipiodol)
 Water insoluble organic iodine compounds(pantopaque).

29. Indications:
1)The presence of calculi
2)To assess extent of ductal & glandular destruction.
3)To determine the extend of glandular breakdown and
crude assessment of function.
Contraindication:
1)Allergic to iodine compounds.
2)Acute infections
3)Calculus close to the ductal opening.

30.  The main pathological changes are:
Ductal changes associated with –
 Calculi
 Sialodochitis (ductal inflammation).
Glandular changes associated with –
 Sialadenitis.(glandular inflammation).
 Sjogren syndrome.
 Intrinsic tumours.

31. Sialographic appearance of calculi

32. Sialographic appearance of
sialodochitis

33. Sialographic appearance of
sialadenitis
Sialectasis – blobs /dots

34. Sialographic appearance in
sjogren syndrome

35. Intercalated ductule & acinus

36. Sialographic appearance of intrinsic
tumors

37. CBCT imaging
 Useful for evaluating structures in & adjacent to
salivary gland
 Cannot resolve soft tissue densities.
 Minimal calcified sialolith well depicted.
 Three D visualization possible.

39. CBCT SIALOGRAPHY IMAGING
 3D reconstruction can be performed and the ductal
architecture viewed in all possible dimensions.
 Information about measurements and location of
sialoliths.
 Highly reliable technique for identifying both
radiopaque as well as radiolucent sialoliths and ductal
strictures.
 Less exposure dose and cost effective.

40. Lateral and axial view

41. Computer tomography
 Useful for evaluating salivary
gland pathology,adjacent
structures and proximity to
facial nerve.
 Calcified structures are
visualized.
 Abscess – hypervascular wall is
evident.
 Definition of cystic walls and
contents.
 Osseous erosions and sclerosis
are visualized.

42. Sialolith

43. CT (contrast) images of enlarged
parotid

44. Multidetector computed
tomographic imaging

45. MRI
 Provides superior soft tissue contrast resolution than
CT.
 Fewer problems with streak artifacts from metallic
dental restoration.
 Image – multiplanar reconstruction software
algorithm.
 iv contrast(gadolinium) – Differentiate cystic & solid
masses.

46. MRI revealing lymphoepithelial
cyst involving right parotid

47. MR sialography
 MRI with evoked
salivation.
 Lemon juice – stimulate
salivation.
 Reveal ductal morphology
accurately ,sialolith
identification
 Alternative to conventional
sialography.

50. Advantages
 Ionizing radiation not used.
 Excellent soft tissue details.
 Differentiate benign & malignant.
 Identify facial n.
 Images in all planes.
 Co- localization with PET scans.
 MR sialography – no contrast.
 MR spectroscopy – differentiate tissues by chemical
constituents.
 In acute stage & cannulation not possible.

51. Disadvantages
 Salivary gland function cannot be determined.
 Limited adjacent hard tissue information.

52. Ultrasound
 High resolution scanners produce excellent images.
Indications:
 Discrete & generalised swelling both intrinsic and
extrinsic to gland.
 Salivary obstruction.
 Differentiate solid masses from cystic ones.
 Guided fine needle aspiration biopsy.

53. *

54. Benign tumour Sialolith

55. Advantages
 Ionisation radiation not used.
 Good imaging of superficial masses.
 Differentiates solid & cystic masses.
 Different echo signals from different tumours
 Blood flow assessment using colour doppler.
 Identify radiolucent stones.
 Lithotripsy of salivary stones.
 Ultra sound aided fine needle aspiration.
 Intraoral US possible with small probes.
 Differentiates intra and extra glandular masses.

56. Disadvantages
 Limited area for investigation.
 No information on fine architecture.

57. Scintigraphy (Nuclear medicine, PET)
 Functional study of salivary glands.
 Iv injection of technetium 99m pertechnetate –
concentrated in and excreated by glandular structures
(salivary, thyroid,mammary ).
 Appearance in ducts max. 30 to 45 min.
 Sialagogue administered to evaluate secretory capacity.
 major salivary glands studied at once.
 High diagnostic sensitivity but lacks specificity.
 Pathosis – increased/decreased/absent radionuclide
uptake.

58. • PET – greater resolution .
• Not used as such.
•Increased uptake of
radioisotope in right
parotid.

59. Sialendoscopy
Sialendoscopy is a
relatively new procedure
that allows endoscopic
transluminal
visualization of major
salivary gland ductal
system and offers a
mechanism for
diagnosing and treating
both inflammatory and
obstructive pathology
related to ductal system

61. Image interpretation of salivary
gland disorders
SIALOLITHIASIS
 radiopaque / radiolucent.(mucous plugs).
 occlusal view, IOPA, Sialography.
 Radiolucent sialolith – ductal filling defect.
 MDCT – minimally calcified sialoliths.
 Ultrasound - > 2mm as echo dense spots with acoustic
shadow.

62. Submandibular calculi

63. Sialolith from phleboliths

64. Sialolith from tonsillolith

65. Sialolith from calcified
lymphnode

66. Bacterial sialadenitis
 Sialography contraindicated in acute infections.
 Chronic cases – Sialectasia
(sac like acinar areas).
 Abscess - seen in
MDCT,US,MRI.

67. Sialodochitis
 Ductal sialadenitis.
 Sialography – sausage string appearance (interstitial
fibrosis).
 Seen in MRI.
 Scintigraphy & CT not indicated.

68. Autoimmune Sialadenitis
 Sialography is helpful.
 Early stage – punctate (<1 mm) & globular (1-2 mm)
collection of contrast media – sialectasia.
 Cavitary sialectases - larger & irregular suggestive of
advanced stage.
 MRI – multiple punctate sialectases.
 US – multiple hypoechoic areas.

70. Sialadenosis
 It is a non neoplastic,noninflammatory
enlargment of parotid gland.
 Sialography - enlargement /normal appearance.
 CT & MRI – straightforward depiction but are
nonspecific.

71. Cystic lesions
 Ultrasound - cyst are sharply marginated and echo
free areas.
 Well circumscribed ,high signal areas on T 2 weighted
MRI.

73. Benign tumors
 Well defined radiolucency - in CT & MRI.
 Contrast agents in CT - >radiopaque due to increased
vascularity of tumor.
 MRI - for submandibular gland neoplasm due to
superior soft tissue resolution.
 USG – benign masses are less echogenic than
parenchyma.
 Sialography – ball in hand.

74. Pleomorphic adenoma
 MDCT – sharply circumscribed ,round homogenous
lesion with high density than adjacent tissue.
 MRI - dark in T 1 weighted images, intermediate in
proton density weighted images & homogenous high
intensity in T 2 weighted images.
 Signal voids – calcification present.

75. Pleomorphic adenoma

76. Warthin’s tumor
 MDCT – soft tissue
/cystic density.
 MRI – heterogenous
with hemorhagic foci.
 USG – solid anechoic.

77. Hemangioma
 Associated with phleboliths
 Plain radiographs and MDCT images.
 MDCT – well defined soft tissue mass.
 MRI – T1 (muscle adjacent)
 T2 – high signal.
 US – hypoechoic hemangioma,phleboliths as multiple
hyperechoic areas .

78. Malignant tumors
 Indicators – illdefined margins,invasion of adjacent
soft tissues,destruction of osseous structures and
perivascular involvement.

79. Mucoepidermoid carcinoma
 Low grade similar to benign.
 High grade – in CT (irregular
homogenous mass).
 In MRI – homogenous & dark
(T1)
 Heterogenous & bright (T2).

81. Other malignant & metastatic tumors
 Adenoid cystic carcinoma

83. Conclusion
 Imaging of the salivary glands uses many different
modalities .
 no established absolute algorithm as to which study
should be performed.
 Depends upon the radiologist preference.

84. References
1)Oral Radiology Principles and Interpretation.Stuart
White,Micheal Pharoah.
2)Salivary gland disorders.Eugene Myers,Robert Ferris.
3)Oral and Maxillo facial radiology. Freny Karjodkar.
4)Textbook of colour atlas of salivary gland
pathology.Eric Carlson,Robert Ford.
5)Atlas of oral diagnostic imaging.Tomomitsu Higashi.
6) Taneja et al. Salivary gland imaging.IJMDS.
7)Yousem et al.Major salivary gland imaging.Radiology.