1. MAJOR SALIVARY GLANDS Prof. Dr. SYED AMIR GILANI
M.B;B.S (Pb) PhD (Swiss)
Afro-Asian Institute of Medical Sciences
Lahore, Pakistan.

2. • Longitudinal and transverse planes
Examination
Scan Planes
• Longitudinal and transverse planes

3. Sonographic Anatomy and Normal Findings
• Sonographic anatomy: The largest of the major salivary glands, the
parotid gland is located anteroinferior to the ear and posterolateral to the ramus of the mandible.

4. Its excretory duct leaves the gland anterosuperior to the buccal mucosa. Generally the duct cannot be denned with ultrasound unless it is enlarged as a result of obstruction.

5. Topographic anatomy of the parotid gland

6. • Normal findings: All of the major salivary glands have smooth, sharp borders and a uniformly hyperechoic texture (similar to the thyroid gland).

7. a, b Oblique scan through the right parotid gland

8. Scanning Protocol
Transducer: 7.5 MHz
The patient is positioned supine, and a wedge may be placed beneath the shoulder.
The neck is hyperextended and turned to the side.

9. • Parotid gland: surveyed in longitudinal and transverse scans (except for the retro-
mandibular part of the gland)
• Submandibular gland: The transducer is positioned lateral to the oral floor on
each side.
• Sublingual gland: The transducer is positioned lateral to the oral floor on each side.

10. Overview and Classification of Findings
• Indication for sonography: As a rule, ultrasound is used specifically to distinguish
between swelling and a tumor (see Peripheral Lymph Nodes,

11. Pathology
• Sialoliths: 80 % of salivary stones occur in the submandibular gland and 20 % in
the parotid gland. The gland may undergo secondary enlargement with a change of internal echo pattern.

12. • Sialadenitis: bacterial or viral (mumps)
• Sialadenosis
• Ductectasia. Stricture?
• Tumors: 78 % are benign, 13 % malignant, 5 % metastatic

13. - Adenomas: pleomorphic adenoma (parotid mixed tumor, 85 %)
- Adenomas: pleomorphic adenoma (parotid mixed tumor, 85 %). oncocytoma,
Whartin tumor
- Nonepithelial tumors
- Secondary tumors (metastases, 5%)

14. Abnormal findings in the salivary glands
Anechoic
Isoechoic or enlarged
Hypoechoic
Hyperechoic
Cysts
Viral sialadenitis
Acute bacterial sialadenitis
Sialadenosis
Abscess
Chronic sialadenitis
Parotid mixed tumor
Lipoma, hemangioma, lymphangioma
Pleomorphic adenoma
Sialolithiasis
Immunogenic sialadenitis
Cystadenolymphoma

15. Abnormal findings in the salivary glands
Anechoic
Isoechoic or enlarged
Hypoechoic
Hyperechoic
Sarcoidosis
Oncocytoma
Mucoepidemoid carcinoma
Adenoid cystic carcinoma
Metastases, malignant lymphoma

16. Abnormal Findings Anechoic Changes • Cysts:
• Clinical features: salivary duct cysts, dysontogenetic duct anomalies, secondary cysts

17. • Causes: inflammation, trauma, sialectasia
• Sonographic features:
- Cystic lesion with smooth or irregular margins
- Cysts always develop at the anterior border of the stemocleidomastoid muscle

18. Abscess
• Ill-defined margins
• Internal echo pattern ranges from anechoic to complex
• Local tenderness

19. Isoechoic Changes and Enlargement
• Viral sialadenitis: e.g., mumps
• Enlargement of the parotid gland
• Normal internal echo pattern

20. a, b Epidemic parotitis, a B-mode image: enlargement of the gland
a, b Epidemic parotitis, a B-mode image: enlargement of the gland. b CDS: inflammatory hypervascularity

21. a, b Inflammation of the submandibular gland: hypoechoic swelling with anechoic streaks (edema)

22. - Chronic sialadenitis:
• Recurrent swelling of the gland

23. Essentially normal echo pattern
• Sialadenosis:
"Hamster cheeks." nonneoplastic. Common in alcoholics, seen occasionally in diabetics (neurogenic?)
• Painless enlargement of the parotid gland
• Nonspecific internal echo pattern
• May be slightly hyperechoic. Fine cysts may be seen

24. Immunogen sialadenitis
• Slight enlargement; nonspecific structure
• Facultative slight hyperechoic; fine cysts
• Sarcoidosis: nonspecific echo pattern, may show decreased echogenicity

25. Sialadenosis. Longitudinal scan shows significant thickening of the parotid gland (cursors)

26. Hypoechoic Changes
• Acute (or chronic recurrent) bacterial sialadenitis ; occurs predominantly in elderly patients with a weakened immune system

27. • Enlargement
• Nonhomogeneous hypoechoic pattern
• Possible findings: liquid foci of abscessation, echogenic structures with acoustic
shadows (sialoliths). Possible anechoic ductal dilatation

28. Acute bacterial parotitis associated with an infected neck cyst
Acute bacterial parotitis associated with an infected neck cyst. Oblique scan shows nonhomogeneous hypoechoic swelling of the parotid gland (P)

29. Parotid mixed tumor (sialadenoma, most common parotid tumor; strong propensity for recurrence, may undergo malignant transformation

30. • Round oval
• Hypoechoic (when large: heterogeneous, cystic/hyperechoic pattern)
• Smooth margins

31. a, b a Parotid mixed tumor (TU)
a, b a Parotid mixed tumor (TU). MAX = maxilla b Cystadenolymphoma (Whartin tumor, cursors). Diagnosed by FNAB

32. Pleomorphic adenoma
may undergo malignant transformation
Smooth margins
Homogeneous

33. • Cystadenolymphoma (Whartin tumor, more common entity; like
oncocytoma, is classified as a sialoma
• Markedly hypoechoic, nonhomogeneous echo pattern
Smooth margins
• Small cysts, may contain fine septations

34. • Uniformly hypoechoic • Smooth margins
Oncocytoma
• rare
• Uniformly hypoechoic
• Smooth margins

35. • Mucoepidermoid carcinoma: low-grade malignancy, the most common
malignant tumor in adults (approximately 50% of malignant salivary gland tumors)
• Very hypoechoic
• Smooth margins
• May contain cystic areas

36. • Adenoid cystic carcinoma (older term: cylindroma): high-grade malignancy
marked by early infiltration of the facial nerve
• Usually hypoechoic. Some lesions are heterogeneous or anechoic
Ill-defined margins

37. • Metastases, malignant lymphoma:
• Hypoechoic round or scalloped mass

38. Lymph node metastases (LN) from bronchial carcinoma: very hypoechoic mass in the parotid gland (P). MAN = mandibular echo with acoustic shadow

39. Hyperechoic Changes Sialadenosis:
Frequently hyperechoic (due to diffuse fatty infiltration)
Bilateral symmetry
Painless enlargement

40. Lipoma, hemangioma, lymphangioma:
Hyperechoic
Lipoma with a feathery pattern; lymphangioma may have a cystic appearance

41. Sialolithiasis (salivary stone
Sialolithiasis (salivary stone. presents clinically with swelling and acute pain
Round or oval hyperechoic mass with an acoustic shadow, projected over the duct

42. Duct obstruction; anechoic duct structure at least 1 mm wide
Rarely intraglandular, usually extraglandular with anteromedial extension into the buccal mucosa

43. a, b Sialolithiasis. a Abnormal anechoic duct structure, b Magnified view with the scan plane positioned for greatest clarity: microliths (arrow) with a distal acoustic shadow (S)

44. Evaluation and Further Testing
Sonography: Diffuse and circumscribed salivary gland lesions can be clearly
visualized with a high-resolution transducer. Most lesions (benign tumors)
occur in the parotid gland.

45. Isoechoic diffuse swelling: usually viral parotitis
Hypoechoic swelling: usually bacterial sialadenitis
Circumscribed hypoechoic tumors: Ultrasound is of limited value for
Benign malignant differentiation

46. Further testing
Circumscribed hypoechoic masses: fine-needle aspiration cytology and histology
Adenoid cystic carcinoma and carcinomas in adenomas: These malignancies often present clinically with rapid growth and facial nerve palsy.

47. Critical: FNAB, surgical diagnosis
Infiltrative growth is clearly demonstrated by CT.
MRI cannot differentiate between benign and malignant lesions (but is useful in the diagnosis of pleomorphic adenoma).

48. Thank You