REF016 - Salivary Gland Imaging Referral Criteria

See REF000 - Referring to Nuclear Medicine (NLAG) for details on how to refer.

Technetium-99m pertechnetate is taken up by salivary glands and secreted by the ductal epithelium. A salivary gland scan can provide physiological information about the ability of the salivary glands to accumulate the radiopharmaceutical and about the drainage of saliva^[1]

Rapid sequential images should show progressive concentration of activity within the salivary glands and the mouth. The thyroid is also visualised and the intensity of activity is generally similar to that in the salivary glands. During imaging, the salivary glands are stimulated to drain by giving the patient lemon juice. When the salivary ducts are patent, this causes prompt salivation and drainage of the glands into the mouth.

In the normal subject, the four salivary glands all accumulate the radiopharmaceutical at the same rate and drain rapidly following stimulation. When a duct is obstructed, the uptake by the gland may be normal or slower than normal and there is no fall of activity following stimulation.

• The referrer may be any clinician holding a current valid medical qualification and currently employed in Secondary Care.
• Referrals from Primary Care will be accepted if the investigation has been suggested by a Consultant Radiologist in a report from a previous investigation or following discussion with a Consultant Radiologist or Secondary Care Specialist. Details of such suggestions or discussions should be included on the request form.

• Sodium chloride for parenteral use (0.9% w/v).

• Patients must fast for at least 2 hours prior to the investigation. They may NOT be given perchlorate^[1].
• Anticholinergic medication should be stopped during 24 h prior to the examination^[1].
• The patient should not take any thyroid blocking agents for up to 48 hours prior to scanning.