Norm of Meckel Scan
Negative; no increased uptake of radionuclide in the right lower quadrant of the abdomen.
Usage of Meckel Scan
Detection of Meckel's diverticulum, which contains ectopic gastric mucosa, in clients with abdominal pain or occult gastrointestinal bleeding.
Description of Meckel Scan
A nuclear medicine scan in which a radioisotope, 99mTc (technetium)-pertechnetate, is injected intravenously. The radioisotope is concentrated in the normal gastric mucosa within the stomach and in the ectopic gastric mucosa in Meckel's diverticulum. This is a very sensitive and specific test for this congenital abnormality.
Professional Considerations of Meckel Scan
Consent form IS required.
During pregnancy or breast-feeding.
- Assure the client that nuclear medicine personnel will remain within hearing range and will be able to see the client throughout the study.
- A histamine (H2)-receptor antagonist (such as cimetidine orally every 6 hours for 24 hours) is usually administered for 1–2 days before the test. This drug inhibits acid secretion and allows for improved visualization of the Meckel's diverticulum.
- See Client and Family Teaching.
- Just before beginning the procedure, take a “time out” to verify the correct client, procedure, and site.
- In the nuclear medicine department, the client lies in a supine position.
- 99mTc-pertechnetate is administered intravenously 15 minutes before imaging.
- An anterior body-image view is obtained with a rectilinear scanner or scintillation (gamma) camera. Images are taken at 5-minute intervals for 1 hour.
- During the scan, the client may be asked to lie on the left side to increase the amount of radioisotope present in the intestines.
- Total examining time is 60 minutes.
- Observe the client carefully for up to 60 minutes after the study for a possible (anaphylactic) reaction to the radionuclide.
- Ask the client to void after the procedure, and a repeat image may be obtained.
- Rubber gloves should be worn for 24 hours after the procedure when urine is being discarded. Wash the gloved hands with soap and water before removing the gloves. Wash the ungloved hands after the gloves are removed.
Client and Family Teaching
- It is necessary to lie still for 60 minutes for this scan. There is no pain associated with this test.
- Refrain from eating or drinking anything for 6–12 hours before the test.
- Void before the study to increase the visibility of the intestines.
- Meticulously wash your hands with soap and water after each void for 24 hours after the procedure.
- Family members must wear rubber gloves for 24 hours after the procedure when discarding the client's urine if the family will be providing this care.
Factors That Affect Results
- A positive scan is dependent on an adequate amount of gastric mucosa within Meckel's diverticulum. Only 25% of clients with Meckel's diverticulum will have sufficient ectopic gastric mucosa to produce a positive scan.
- Meckel scan is unreliable for evaluation of gastrointestinal bleeding.
- Other radionuclide studies performed within the previous 24 hours will interfere with this test.
- A waiting period that is either too short or too long after the radionuclide injection will alter the results.
- Premedication with pentagastrin and a histamine (H2)-receptor blocker (Zantac) may increase the sensitivity of the test.
- Barium in the small or large bowel may mask the radionuclide concentration.
- Health care professionals working in a nuclear medicine area must follow federal standards set by the Nuclear Regulatory Commission. These standards include precautions for handling the radioactive material and monitoring of potential radiation exposure.
- The half-life of technetium is 6 hours.