REF026 - Meckel's Diverticulum Imaging

See REF000 - Referring to Nuclear Medicine (NLAG)

Meckel’s Diverticulum is the commonest congenital anomaly of the gastrointestinal tract and is often a coincidental finding. Approximately 5% of Meckel’s diverticulae contain ectopic gastric mucosa. This mucosa is a well documented cause of acute gastrointestinal bleeding and may also cause abdominal pain. Those diverticulae that bleed usually present in children or young adults with rectal bleeding or melaena. Diverticulae are variable in position, most commonly appearing in the lower abdomen, usually in the ileum.

Technetium-99m pertechnetate accumulates in gastric mucosal cells and can be used to detect sites of ectopic gastric mucosa. A positive investigation shows a small localised area of radiopharmaceutical uptake which appears at the same time as the stomach and accumulates activity at the same rate as the stomach.

The referrer may be any clinician holding a current valid medical qualification and currently employed in Secondary Care.

Referring clinicians are reminded of the requirement to avoid unnecessary exposure to ionising radiation. The investigation may already have been requested at this hospital or elsewhere and clinicians are asked to be particularly vigilant to ensure that their request is not a double request.

• Sodium chloride for parenteral use (0.9% w/v).
• Proton Pump Inhibitor, usually Omeprazole or Histamine H2 receptor antagonist, usually Cimetidine.

• Ideally the patient should fast for four hours prior to the test, however this is not essential and failure to fast should not prevent the test from being performed. ^[1]
• Pre-treatment with a Proton Pump Inhibitor, usually Omeprazole. (Adults and children >20kg: 40mg daily, orally, on the morning preceding the scan and again on the morning of the scan. For children weighing between 10-19kg: 20mg daily, orally, on the morning preceding the scan and again on the morning of the scan^{[1] [2]}).
  • For children under 1 year old/under 10kg, advice must be sought from the referring clinician about the pre-treatment.
  • Omeprazole is available as an oral liquid and as oro-dispersible tablets if required.
  • If the scan is urgent, one day of pre-treatment with Omeprazole is sufficient, if agreed by the ARSAC licence holder.
  • Alternatives such as cimetidine may be used at the discretion of the ARSAC licence holder.
  • Pre-treatment can be omitted if the patient is already on a proton pump inhibitor.
• Currently, all supplementary medications for this investigation need to be prescribed by the referring clinician.

Sufficient clinical information must be provided to justify the investigation proceeding.

The clinical indications are detailed below.