Investigations

Investigative options for suspected submandibular calculi include:

• plain X-rays:
  • occlusal and lateral-oblique views
  • demonstrate most calculi
  • 20% of calculi are radiolucent and hence undetectable
    
    
• sialiography - contrast radiography of the duct system:
  • distinguishes calcification not related to the gland and its duct
  • sialography allows examination of the architecture of the salivary gland and duct

Other investigations:

• ultrasonography, computed tomography and magnetic resonance imaging are particularly useful in evaluating masses in the salivary glands (1)
  • ultrasonography
    • can be used to differentiate between solid versus cystic lesions of the gland
    • can be used to differentiate intrinsic from extrinsic disease
    • helpful in identification of abscess formation
  • computed tomography scanning
    • useful in differentiating intrinsic versus extrinsic glandular disease
    • also can be used in defining abscess formation versus phlegmon
    • limited usefulness in evaluation of ductal system unless combined with simultaneous sialography
  • magnetic resonance imaging
    • does not allow evaluation of the ductal system, and it is not helpful in defining calcifications.
    • excellent tool for soft tissue definition (invaluable in instances of suspected neoplasia)

Reference:

1. Can Assoc Radiol J. 1993 Oct;44(5):342-9